Preconceptional Counselling and Prenatal Care.pdf

CHAPTER 9 Preconceptional Counseling COUNSELING SESSION MEDICAL HISTORY GENETIC DISEASES REPRODUCTIVE HISTORY PARENTAL AGE SOCIAL HISTORY SCREENING TESTS REFERENCES The Centers for Disease Control and Prevention (CDC) defines preconceptional health to encompass the overall health of nonpregnant w...

CHAPTER 9 Preconceptional Counseling COUNSELING SESSION MEDICAL HISTORY GENETIC DISEASES REPRODUCTIVE HISTORY PARENTAL AGE SOCIAL HISTORY SCREENING TESTS REFERENCES The Centers for Disease Control and Prevention (CDC) defines preconceptional health to encompass the overall health of nonpregnant women during their reproductive years (Robbins, 2018). The American College of Obstetricians and Gynecologists (2019b) and the Society for Maternal–Fetal Medicine (2014, 2021) attest to the importance of preconceptional care and promote the following objectives to advance it: 1. Improve knowledge, attitudes, and behaviors of men and women related to preconceptional health 2. Assure that all childbearing-aged women receive preconceptional care services—including evidence-based risk screening, health promotion, and interventions—that will enable them to enter pregnancy in optimal health 3. Implement interconceptional interventions to prevent or minimize recurrent adverse outcomes 4. Reduce the racial and socioeconomical disparities in adverse pregnancy outcomes Table 9-1 lists the prevalence of many conditions often amenable to preconceptional intervention (Robbins, 2018). These are frequently encountered by generalist obstetrician–gynecologists, who can help optimize health entering pregnancy (Arluck, 2018). For example, by the time most women realize they are pregnant—usually 1 to 2 weeks after the first missed period—the embryo has already begun to form. Thus, many preventive steps —such as folic acid to avoid neural-tube defects—will be ineffective if initiated at this time. Moreover, 45 percent of all pregnancies in the United States are unplanned, and often these are at greatest risk (Finer, 2016). Last, a disproportionate number of indigent women receive less preconceptional care compared with their more affluent counterparts (Easter, 2017). TABLE 9-1. Preconceptional Health Indicators—United States, 2013–2015 Few randomized trials evaluate preconceptional care efficacy, in part because withholding such counseling would be unethical. Also, pregnancy outcomes are dependent on the interaction of various maternal, fetal, and environmental factors. Thus, ascribing a salutary outcome to a specific intervention is difficult (Temel, 2014; Tieu, 2017). However, prospective observational and case-control studies have demonstrated the successes of preconceptional counseling (Yamamoto, 2018). Therefore, routine pregnancy intention screening should be done (Manze, 2020). COUNSELING SESSION Obstetricians–gynecologists, internists, family practitioners, and pediatricians have the best opportunity to provide preventive counseling during periodic health maintenance examinations. The occasion of a negative pregnancy test is also an excellent time for education (Skogsdal, 2018). Jack and colleagues (1995) administered a comprehensive preconceptional risk survey to 136 such women, and almost 95 percent reported at least one problem that could affect a future pregnancy (see Table 9-1). Providers should be knowledgeable regarding relevant medical diseases, prior surgery, reproductive disorders, or genetic conditions and be able to interpret data and recommendations provided by other specialists (Simpson, 2014). Women presenting specifically for preconceptional evaluation are advised that information collection may be time consuming, depending on the number and complexity of factors. The intake evaluation includes a thorough review of the medical, obstetrical, social, and family histories. Useful information is more likely to be obtained by asking specific questions regarding each of these histories and the health of each family member than by asking general, open-ended questions. Some important information can be obtained by questionnaires that address these topics. Answers are reviewed with the couple to ensure appropriate follow-up, including obtaining relevant medical records. The Fourth Trimester Another optimal time to begin preconceptional counseling is during the “fourth trimester.” This was emphasized by the Presidential Task Force on Redefining the Postpartum Visit (American College of Obstetricians and Gynecologists, 2018e). Designed to optimize postpartum care and provide contraceptive counseling, it also sets the stage for any subsequent pregnancy and for the woman’s long-term health. To assist the provider, the American College of Obstetricians and Gynecologists (2019b) has joined the Society of Maternal–Fetal Medicine to provide an Obstetric Care Consensus guide that emphasizes the interpregnancy period. MEDICAL HISTORY With specific medical conditions, general points include the pregnancy’s effect on the condition and the disorder’s influence on the fetus and pregnancy course. Some chronic conditions that may worsen pregnancy outcomes include treated or active cancer, prior peripartum cardiomyopathy, antiphospholipid antibodies, systemic lupus erythematosus, and congenital heart disease (Amant, 2015; Cunningham, 2019; Davis, 2021; Foeller, 2018; Gibbins, 2018; Hopkins, 2018). Importantly, psychological health also is considered (Barker, 2020; Lassi, 2014). Detailed preconceptional information regarding a few exemplary conditions is found in the next sections and in the other topic-specific chapters of this text. Diabetes Mellitus Because maternal and fetal pathology associated with hyperglycemia is well known, diabetes is the prototype of a condition for which preconceptional counseling is beneficial. Diabetes-associated risks to both mother and fetus are discussed in detail in Chapter 60 (p. 1068). If a patient maintains glucose levels close to normal, many of these complications can be avoided before conception. Another important aspect of counseling pertains to the frequent use of teratogenic angiotensin-converting enzyme inhibitors in this population (Podymow, 2015). The American College of Obstetricians and Gynecologists (2018f) has concluded that preconceptional counseling for women with pregestational diabetes is beneficial and cost-effective and should be encouraged. The American Diabetes Association (2004) has promulgated consensus recommendations for preconceptional care for women with diabetes. These guidelines advise an inventory of disease duration and related complications and clinical and laboratory examination for end-organ damage. Perhaps most essential, they encourage a preconceptional hemoglobin A1c level goal below 7 percent. In addition to assessing diabetic control, hemoglobin A1c measurement can also forecast the risks for gestational diabetes and for major anomalies (Fig. 9-1) (Hinkle, 2018; Martin, 2020). FIGURE 9-1 Relationship between first-trimester glycosylated hemoglobin values and risk for major congenital malformations in 320 women with insulin-dependent diabetes. Although no randomized trials attest to the success of preconceptional counseling in women with diabetes, cohort studies do demonstrate its effectiveness (Tieu, 2017). In a prospective study of 5075 affected women, preconceptional counseling improved hemoglobin A1c levels, folic acid compliance, and “optimal” pregnancy preparation (Yamamoto, 2018). Diabetic women who undergo preconceptional counseling also have improved glycemic control before pregnancy and in the first trimester and experience lower rates of adverse outcomes—defined as a perinatal death or major congenital anomaly (Tripathi, 2010). Despite such benefits, in one study of approximately 300 diabetic women in a managed-care plan, only approximately half received preconceptional counseling (Kim, 2005). Epilepsy Compared with unaffected women, those with a seizure disorder carry an augmented risk of neonates with structural anomalies. Some early reports indicated that epilepsy conferred an elevated a priori risk for congenital malformations that was independent of anticonvulsant treatment effects. More recent studies have largely failed to confirm this, but it is difficult to refute entirely because women who are controlled without medication generally have less severe disease (Cassina, 2013; Vajda, 2015). Polytherapy is associated with a higher malformation risk compared with monotherapy (Bromley, 2017). Last, in women using antiseizure medications, the risks for miscarriage and stillbirth in do not appear elevated (Aghajanian, 2015; Bech, 2014). Ideally, medications are adjusted preconceptionally to minimize seizure frequency. From one national registry, the seizure risk during pregnancy was 50 to 70 percent lower in women without a seizure in the year preceding pregnancy compared with a group experiencing seizures in this preceding year (Vajda, 2008). No further advantages accrued if the seizure-free period exceeded a year. Treatment goals attempt to control seizure frequency with monotherapy and with medications considered less teratogenic (Aguglia, 2009; Tomson, 2009). Discussed in Chapter 63 (p. 1129) and shown in Table 9-2, some one- drug regimens are more teratogenic than others. In particular, valproic acid is avoided if possible, as it has consistently been associated with a greater risk for major congenital malformations than other antiepileptic drugs (Jentink, 2010; Vajda, 2015). Information concerning the teratogenicity of newer antiepileptics is limited (Knight, 2021). TABLE 9-2. First-Trimester Antiepileptic Monotherapy and the Associated Major Malformation Risk  The American Academy of Neurology recommends consideration of antiseizure medication discontinuation before pregnancy in suitable candidates (Jeha, 2005). These include women who satisfy the following criteria: (1) have been seizure-free for 2 to 5 years, (2) display a single seizure type, (3) have a normal neurological examination and normal intelligence, and (4) show electroencephalogram results that have normalized with treatment. Women with seizures should be advised to take a daily 4-mg oral folic acid supplement. Even so, the value of folate to reduce fetal malformation rates in pregnant women taking anticonvulsant therapy is not entirely clear. In one case-control study, the congenital abnormality risk was reduced by maternal folate supplementation in fetuses exposed to carbamazepine, phenobarbital, phenytoin, and primidone (Kjær, 2008). Conversely, Morrow and coworkers (2009) compared fetal outcomes of women who received preconceptional folic acid with those who did not receive it until later in pregnancy or not at all. In this study, a paradoxical increase in the number of major congenital malformations was observed in the group who received preconceptional folate. These investigators concluded that folate metabolism may be only a part of the mechanism by which malformations are induced in women taking these medications. Immunizations Preconceptional counseling includes assessment of immunity against common pathogens. Also, depending on health status, travel plans, and time of year, other immunizations may be indicated as discussed in Chapter 10 (p. 189). Several immunization resources are listed in Table 9-3. Vaccines that contain toxoids such as tetanus are suitable before or during gestation. Also, those containing killed bacteria or viruses—such as influenza, pneumococcus, hepatitis B, meningococcus, and rabies vaccines—are not associated with adverse fetal outcomes and are not contraindicated preconceptionally or during pregnancy. Conversely, live-virus vaccines are not recommended during pregnancy. Examples are vaccines against varicella-zoster, measles, mumps, rubella, polio, chickenpox, and yellow fever. Moreover, 1 month or longer should ideally pass between vaccination and conception attempts. That said, inadvertent administration of measles, mumps, rubella (MMR) or varicella vaccines during pregnancy should not generally be considered indications for pregnancy termination. Most reports indicate that the fetal risk is only theoretical. Immunization to smallpox, anthrax, and other bioterrorism diseases is discussed if clinically appropriate (Chap. 67, p. 1200). TABLE 9-3. Immunization Resources With some infections, vaccines are unavailable. One recent example is the Zika virus (Brasil, 2016). For this virus, during the 2016 epidemic, the CDC issued travel advisories for pregnant women (Petersen, 2016; Schuler- Faccini, 2016). GENETIC DISEASES The CDC (2016) estimates that 3 percent of neonates born each year in the United States will have at least one birth defect. Importantly, such defects are the leading cause of infant mortality and account for 20 percent of deaths. Ethics preclude randomized trials of preconceptional counseling for genetic risk (Hussein, 2018). Instead, the benefits of preconceptional counseling usually are measured by comparing the incidence of new cases before and after initiation of such a program. Specific congenital conditions that clearly benefit from patient education include neural-tube defects, phenylketonuria, thalassemias, and other genetic diseases more common in individuals of Eastern European Jewish descent (King, 2018). Other missed opportunities for genetic consultation were found for women with a personal or family history of birth defects, intellectual disability or autism, and a prior positive genetic carrier screening test (McClatchey, 2018). Family History Pedigree construction using the symbols shown in Figure 9-2 is the most thorough method for obtaining a family history as a part of genetic screening. The health and reproductive status of each “blood relative” are individually reviewed for medical illnesses, mental retardation, birth defects, infertility, and pregnancy loss. Certain racial, ethnic, or religious backgrounds may indicate elevated risk for specific recessive disorders. FIGURE 9-2 Symbols used for pedigree construction. Although most women can provide information regarding their history, their understanding may be limited. Pregnant women may fail to communicate a birth defect in the family or may report it incorrectly. Thus, any disclosed defect or genetic disease is ideally confirmed by reviewing pertinent medical records or by contacting affected relatives for additional information.  Neural-Tube Defects The incidence of neural-tube defects (NTDs) is 0.9 per 1000 live births, and they are second only to cardiac anomalies as the most frequent structural fetal malformation. Some of these malformations are associated with specific mutations. One example is the 677C → T substitution in the gene that encodes methylene tetrahydrofolate reductase. For this and similar gene defects, one seminal trial showed that preconceptional folic acid therapy significantly reduced the risk for a recurrent NTD by 72 percent (Medical Research Council Vitamin Study Research Group, 1991). More importantly, because more than 90 percent of neonates with NTDs are born to women at low risk, Czeizel and Dudas (1992) showed that universal supplementation reduced the a priori risk of a first NTD. Because of these findings, all women who may become pregnant are recommended to take daily 400 to 800 μg of folic acid orally before conception and through the first trimester (U.S. Preventive Services Task Force, 2019). Folate fortification of cereal grains has been mandatory in the United States since 1998, and this practice has lowered neural-tube defect rates (Williams, 2015). Despite the demonstrated benefits of folate supplementation, only half of women take folic acid supplementation periconceptionally (de Jong-van den Berg, 2005; Goldberg, 2006). Phenylketonuria More than 600 mutations have been identified in the phenylalanine hydroxylase gene. The inherited defect in phenylalanine metabolism exemplifies diseases in which the fetus may not be at risk to inherit the disorder but may be damaged by maternal disease. Specifically, mothers with phenylketonuria (PKU) who eat an unrestricted diet have abnormally high blood phenylalanine levels. This amino acid readily crosses the placenta and can damage developing fetal organs, especially neural and cardiac tissues. With appropriate preconceptional counseling and adherence to a phenylalanine-restricted diet before pregnancy, the incidence of fetal malformations is dramatically reduced (Camp, 2014; Vockley, 2014). Therefore, the phenylalanine concentration is ideally brought into normal range 3 months before conception and then maintained there throughout pregnancy (American College of Obstetricians and Gynecologists, 2020a). The target phenylalanine blood concentration is 120 to 360 µmol/L (Camp, 2014). Thalassemias These disorders of globin-chain synthesis are the most common single-gene disorders worldwide (Forget, 2013; Vichinsky, 2013). As many as 200 million people carry a gene for one of these hemoglobinopathies, and hundreds of mutations are known to cause thalassemia syndromes (Chap. 59, p. 1053). In endemic areas such as Mediterranean and Southeast Asian countries, counseling and other prevention strategies have reduced the incidence of new cases by up to 80 percent (Cao, 2013). The American College of Obstetricians and Gynecologists (2018a) recommends that individuals of high-risk ancestry be offered carrier screening to allow them informed decision-making regarding reproduction and prenatal diagnosis. One method of early prenatal diagnosis for some thalassemia syndromes is preimplantation genetic testing (PGT), which is coupled with assisted reproductive technology (Chap. 17, p. 348). Individuals of Eastern European Jewish Descent Most individuals of Jewish ancestry in North America are descended from Ashkenazi Jewish communities and are at greater risk for having offspring with one of several autosomal recessive disorders. These include Tay-Sachs disease, Gaucher disease, cystic fibrosis, Canavan disease, familial dysautonomia, mucolipidosis IV, Niemann-Pick disease type A, Fanconi anemia group C, and Bloom syndrome. The American College of Obstetricians and Gynecologists (2017a; 2019a) recommends preconceptional counseling and screening for these disorders in this population. Carrier frequency and features of these conditions are discussed in greater detail in Chapter 17 (p. 343). REPRODUCTIVE HISTORY During preconceptional screening, information is sought regarding infertility; abnormal pregnancy outcomes that may include miscarriage, ectopic pregnancy, molar pregnancy, and recurrent pregnancy loss; and obstetrical complications such as cesarean delivery, preeclampsia, placental abruption, and preterm delivery (Stubblefield, 2008). As discussed in Chapter 35 (p. 626), details involving a prior stillbirth are especially important. For example, Korteweg and associates (2008) identified chromosomal abnormalities in 13 percent of stillborns who underwent karyotyping. And, Reddy and colleagues (2012) confirmed that chromosomal microarray analysis (CMA) yields better detection of genetic abnormalities than does standard karyotyping. This primarily stems from CMA’s ability to assess nonviable tissue (Chap. 16, p. 325). Identification of a genetic abnormality in a stillborn can help to determine recurrence risk. PARENTAL AGE Maternal Age Women at both ends of the reproductive-age spectrum have unique outcomes to consider. First, according to the CDC, 3.4 percent of births in the United States in 2010 were in women aged 15 to 19 years (Martin, 2012). An international study reported a rate of 11.9 percent for this age group globally (Althabe, 2015). These adolescents are at higher risk for anemia, preterm delivery, and preeclampsia compared with women aged 20 to 35 years (Usta, 2008). The incidence of sexually transmitted diseases—common in adolescents—is even higher during pregnancy (Niccolai, 2003). Unfortunately, because most of their pregnancies are unplanned, adolescents rarely seek preconceptional counseling. Conceptions after age 35 currently constitute approximately 15 percent of pregnancies in the United States (Martin, 2012). By contrast, these women are more likely to request preconceptional counseling. Motivations may stem from a desire to optimize outcomes at their age or with infertility treatment or both. Some studies—including data from Parkland Hospital presented in Figure 9-3–indicate that risks for obstetrical complications and for perinatal morbidity and mortality rise after age 35 (Waldenström, 2015). The older woman who has a chronic illness or who is in poor physical condition usually has readily apparent risks. For the physically fit woman without medical problems, however, the risks are lower. FIGURE 9-3 Incidence of selected pregnancy complications in relation to maternal age among 295,667 women delivered at Parkland Hospital. Overall, the maternal mortality rate is higher in women aged 35 and older (Chap. 1, p. 5). Creanga and coworkers (2017) analyzed pregnancy-related deaths in the United States for 2011 through 2013. Although women older than 35 years contributed less than 15 percent of all live births, they constituted 31 percent of maternal deaths. For the fetus, maternal age-related risks primarily originate from (1) indicated preterm delivery for maternal complications such as hypertension and diabetes, (2) spontaneous preterm birth, (3) fetal-growth disorders related to chronic maternal disease or multifetal gestation, (4) fetal aneuploidy, and (5) pregnancies resulting from assisted reproductive technology. Assisted Reproductive Technologies Recall that older women have subfertility problems. And, although the incidence of dizygotic twinning rises with maternal age, the more important cause of multifetal gestation in older women follows the use of assisted reproductive technology (ART) and ovulation induction. Indeed, according to the CDC, 30 to 40 percent of all multifetal gestations in the United States in 2012 were conceived with the use of ART (Sunderan, 2015). Morbidity and mortality with multifetal pregnancies stem from preterm delivery and placentation complications, such as placenta previa and abruption (Qin, 2016). With ART, transmission of infectious agents is a risk. For women without human immunodeficiency virus (HIV) infection who plan conception with their HIV-affected partners, the CDC has published prevention strategies (Kawwass, 2017). Also, Zika virus infection acquisition through in vitro fertilization (IVF) has been described (Washington Cross, 2017). Last, some data links ART to higher major congenital malformation rates. In a registry of 308,974 births, 8.3 percent of neonates conceived by ART had major birth defects, and intracytoplasmic injection was also associated with an elevated risk for malformations (Davies, 2012). Paternal Age Advanced paternal age has doubled in the United States over the past generation. It is associated with a higher risk of preterm birth and new autosomal-dominant mutations (Chap. 16, p. 320) (Khandwala, 2018). One example is the possible link between increasing paternal age and complex neuropsychiatric conditions (Malaspina, 2015). Parental history and experiences can also exert effects on progeny through epigenomic information not contained in the DNA sequence. Variations in sperm and oocyte cytosine methylation and noncoding RNAs are examples (Cedars, 2015; Lane, 2014). SOCIAL HISTORY Recreational Drugs and Smoking Fetal risks associated with alcohol, marijuana, cocaine, amphetamines, and heroin are discussed in Chapters 8 (p. 148) and 64 (p. 1150). The first step in preventing drug-related fetal risk is an honest assessment of use by the patient (American College of Obstetricians and Gynecologists, 2017c). Toward this end, questioning should be nonjudgmental.  Several validated tools screen for at-risk drinking. One is the well- studied TACE questions (American College of Obstetricians and Gynecologists, 2019d). These four questions investigate having a tolerance to alcohol, being annoyed by comments about their drinking, attempting to cut down, and drinking early in the morning—the eye opener. Of more than 1000 postpartum patients in one Canadian study, a high percentage reported alcohol use concurrent with conception attempts (Tough, 2006). Specifically, nearly half of those planning for pregnancy consumed a mean of 2.2 drinks daily during early gestation and before they recognized their pregnancy. This frequency and pattern clearly underscore the opportunity for preconceptional counseling. In 2014 to 2015, 17 percent of reproductive-age women in the United States smoked cigarettes according to the CDC (Robbins, 2018). Smoking in pregnancy is consistently associated with numerous adverse perinatal outcomes (Chap. 8, p. 156). These risks are largely mitigated by cessation before pregnancy, highlighting the importance of screening for tobacco use prior to and during pregnancy (Chap. 10, p. 179). Environmental Exposures Only a few environmental agents have been shown to cause adverse pregnancy outcomes (McCue, 2019; Windham, 2008). For example, contact with some chemicals may impart significant maternal and fetal risks. Discussed in Chapter 8 (p. 153), excess exposure to methyl mercury or lead is associated with neurodevelopmental disorders. For lead, the American College of Obstetricians and Gynecologists (2018b) endorses guidelines that recommend blood lead testing only if a lead-exposure risk factor is identified. If the levels are >5 µg/dL, counseling is completed, and the lead source is sought and removed. Blood lead levels >45 µg/dL are consistent with lead poisoning, and women in this group may be candidates for chelation therapy (Centers for Disease Control and Prevention, 2019). In contrast, everyday exposures to electromagnetic fields are not linked to adverse fetal outcomes (Robert, 1999). Examples include energy emanated by high-voltage power lines, electric blankets, microwave ovens, and cellular phones.  Diet Pica is the craving for and consuming of ice, laundry starch, clay, dirt, or other nonfood items. It should be discouraged due to its inherent replacement of healthful food with nutritionally empty products (Chap. 10, p. 191). In some cases, it may represent an unusual physiological response to iron deficiency (Epler, 2017). Many vegetarian diets are protein deficient but can be corrected by increasing egg and cheese consumption. Anorexia and bulimia raise maternal risks of nutritional deficiencies, electrolyte disturbances, cardiac arrhythmias, and gastrointestinal pathology (American Psychiatric Association, 2013). Discussed in Chapter 64 (p. 1149), pregnancy-related complications with these eating disorders include greater risks of low birthweight, smaller head circumference, microcephaly, and small-for-gestational-age newborns. Obesity is linked with several maternal complications. Discussed in Chapter 51 (p. 905), these include hypertension, preeclampsia, gestational diabetes, labor abnormalities, cesarean delivery, and operative complications (American College of Obstetricians and Gynecologists, 2018d). Obesity also appears to be associated with a range of structural fetal anomalies (Stothard, 2009). Exercise Conditioned pregnant women usually can continue to exercise throughout gestation (American College of Obstetricians and Gynecologists, 2020b). Discussed in Chapter 10, covering prenatal care (p. 187), no data suggest that exercise is harmful during pregnancy. However, as pregnancy progresses, balance problems and joint relaxation may predispose to orthopedic injury. During exercise, gravidas should avoid exhaustion, overheating, dehydration, and prolonged supine position. Intimate-Partner Violence Pregnancy can exacerbate interpersonal problems and is a time of elevated risk from an abusive partner. According to the American College of Obstetricians and Gynecologists (2012), approximately 324,000 pregnant women are abused each year. Intimate-partner violence (IPV) is associated with greater risk for several pregnancy-related complications that include hypertension, vaginal bleeding, hyperemesis, preterm delivery, and low- birthweight neonates (Chap. 50, p. 891) (Silverman, 2006). Because IPV can escalate during pregnancy, even to the point of homicide, the preconceptional period provides an ideal time for screening and intervention (Cheng, 2010). In support, the American College of Obstetricians and Gynecologists (2019c) provides recommendations and resources for screening both pregnant and nonpregnant women for IPV. Lesbian, Gay, Bisexual, Transgender, and Queer Individuals Preconceptional care has traditionally been based on the assumption of heterosexuality and has often excluded lesbian women (Bushe, 2017). The American College of Obstetricians and Gynecologists (2018c) endorses quality health care for all women regardless of sexual orientation. Indeed, in a study by Carpinello and colleagues (2016), three fourths of lesbian couples planned for one partner to conceive. Paradoxically, adolescent bisexual and lesbian women are at greater risk for undesired pregnancies (Charlton, 2018; Hodson, 2017). Of special risks in this group, lesbian and bisexual women have higher incidences of obesity, tobacco and alcohol use, depression, diabetes, and low parity compared with heterosexual women (Mravcak, 2006; O’Hanlan, 2007). In some of these groups, knowledge of surrogacy laws is imperative (Tsai, 2020). SCREENING TESTS Highlighted in Table 9-4, women with certain chronic medical diseases ideally would be evaluated before conception. With several of these, optimizing maternal condition will improve pregnancy outcomes. TABLE 9-4. Selected Preconceptional Counseling Topics REFERENCES Aghajanian P, Gupta M: Helping your epileptic patient. Contemp OB/GYN 60:10, 2015 Aguglia U, Barboni G, Battino D, et al: Italian consensus conference on epilepsy and pregnancy, labor and puerperium. Epilepsia 50:7, 2009 Althabe F, Moore JL, Gibbons L, et al: Adverse maternal and perinatal outcomes in adolescent pregnancies: the Global Network’s Maternal Newborn Health Registry Study. Reprod Health 12 Suppl:S8, 2015 Amant F, Vandenbroucke T, Verheecke M, et al: Pediatric outcome after maternal cancer diagnosed during pregnancy. N Engl J Med 373(19):1824, 2015 American College of Obstetricians and Gynecologists: Carrier screening for genetic conditions. Committee Opinion No. 691, March 2017a American College of Obstetricians and Gynecologists: Marijuana use during pregnancy and lactation. Committee Opinion No. 722, July 2015, Reaffirmed 2017c American College of Obstetricians and Gynecologists: Hemoglobinopathies in pregnancy. Practice Bulletin No. 78, January 2007, Reaffirmed 2018a American College of Obstetricians and Gynecologists: Lead screening during pregnancy and lactation. Committee Opinion No. 533, August 2012, Reaffirmed 2018b American College of Obstetricians and Gynecologists: Marriage and family building equality for lesbian, gay, bisexual, transgender, queer, intersex, asexual, and gender nonconforming individual. Committee Opinion No. 749, July 2018c American College of Obstetricians and Gynecologists: Optimizing postpartum care. Committee Opinion No. 736, May 2018e American College of Obstetricians and Gynecologist: Pregestational diabetes mellitus. Practice Bulletin No. 201, November 2018f American College of Obstetricians and Gynecologists: Carrier screening in the age of genomic medicine. Committee Opinion No. 690, March 2017, Reaffirmed 2019a American College of Obstetricians and Gynecologists: Interpregnancy care. Obstetric Care Consensus Number 8, January 2019b American College of Obstetricians and Gynecologists: Intimate partner violence. Committee Opinion No. 518, February 2012, Reaffirmed 2019c American College of Obstetricians and Gynecologists: At-risk drinking and alcohol dependence: obstetric and gynecologic implications. Committee Opinion No. 496, August 2011, Reaffirmed 2019d American College of Obstetricians and Gynecologists: Management of women with phenylalanine hydroxylase deficiency. Committee Opinion No. 802, March 2020a American College of Obstetricians and Gynecologists: Physical activity and exercise during pregnancy and the postpartum period. Committee Opinion No. 804, March 2020b American College of Obstetricians and Gynecologists: Obesity in pregnancy. Practice Bulletin No. 230, May 2021 American Diabetes Association: Preconception care of women with diabetes. Diabetes Care. 27 Suppl 1:S76, 2004 American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 5th ed. Arlington, American Psychiatric Association, 2013 Arluck JC, Mayhew AC: Preconception care for the general Ob/Gyn. Clin Obstet Gynecol 61(1):62, 2018 Barker LC, Dennis CL, Hussain-Shamsy N, et al: Decision-making about antidepressant medication use in pregnancy: a comparison between women making the decision in the preconception period versus in pregnancy. BMC Psychiatry 20(1):54, 2020 Bech BH, Kjaersgaard MI, Pedersen HS, et al: Use of antiepileptic drugs during pregnancy and risk of spontaneous abortion and stillbirth: population based cohort study. BMJ 349:g5159, 2014 Bennett RL, French KS, Resta RG, et al: Standardized human pedigree nomenclature: update and assessment of the recommendations of the National Society of Genetic Counselors. J Genet Counsel 17(5):424, 2008 Brasil P, Pereira JP, Gabaglia CR, et al: Zika virus infection in pregnant women in Rio de Janeiro— preliminary report. N Engl J Med 375(24):2321, 2016 Bromley RL, Weston J, Marson AG: Maternal use of antiepileptic agents during pregnancy and major congenital malformations in children. JAMA 318(17):1700, 2017 Bushe S, Romero IL: Lesbian pregnancy: care and considerations. Semin Reprod Med 35(5):420, 2017 Camp KM, Paris MA, Acosta PB, et al: Phenylketonuria scientific review conference: state of the science and future research needs. Mol Genet Metab 112(2):87, 2014 Cao A, Kan YW: The prevention of thalassemia. Cold Spring Harb Perspect Med 3(2):a011775, 2013 Carpinello OJ, Jacob MC, Nulsen J, et al: Utilization of fertility treatment and reproductive choices by lesbian couples. Fertil Steril 106(7):1709, 2016 Cassina M, Dilaghi A, Di Gianantonio E, et al: Pregnancy outcome in women exposed to antiepileptic drugs: teratogenic role of maternal epilepsy and its pharmacologic treatment. Reprod Toxicol 39:50, 2013 Cedars MI: Introduction: childhood implications of parental aging. Fertil Steril 103(6):1379, 2015 Centers for Disease Control and Prevention: Recommended actions based on blood lead level. 2019. Available at: https://www.cdc.gov/nceh/lead/advisory/acclpp/actions-blls.htm. Accessed January 30, 2020 Centers for Disease Control and Prevention: COVID-19 vaccines while pregnant or breastfeeding. 2021. Available at: https://www.cdc.gov/coronavirus/2019- ncov/vaccines/recommendations/pregnancy.html. Accessed October 8, 2021 Charlton BM, Roberts AL, Rosario M, et al: Teen pregnancy risk factors among young women of diverse sexual orientations. 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Diabetologia 61(7):1528, 2018 CHAPTER 10 Prenatal Care PRENATAL CARE IN THE UNITED STATES DIAGNOSIS OF PREGNANCY INITIAL PRENATAL EVALUATION SUBSEQUENT PRENATAL VISITS NUTRITIONAL COUNSELING COMMON CONCERNS REFERENCES The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists (2017) define prenatal care as “A comprehensive antepartum program involves a coordinated approach to medical care, continuous risk assessment, and psychosocial support that optimally begins before pregnancy and extends throughout the postpartum and interpregnancy period.” As promulgated by John Ballantyne, such care has been a bedrock to improve pregnancy outcomes for more than 100 years (Reiss, 2000). PRENATAL CARE IN THE UNITED STATES Almost a century after its introduction, prenatal care has become one of the most frequently used health services in the United States. According to the Centers for Disease Control and Prevention (CDC), only 1.6 percent of women who gave birth in 2016 received no prenatal care (Osterman, 2018). African-American and Hispanic women have high rates of inadequate or no prenatal care that reach 10 and 7.7 percent, respectively. This figure is greater for adolescents, particularly those younger than 15 years, compared with older age groups. These data highlight areas of potential improvement by the health-care system. Prenatal Care Effectiveness Care designed during the early 1900s focused on lowering the extremely high maternal mortality rate. Prenatal care undoubtedly contributed to the dramatic decline in maternal deaths from 690 per 100,000 births in 1920 to 50 per 100,000 by 1955 (Loudon, 1992). Data from 1998 to 2005 from the Pregnancy Mortality Surveillance System identified a fivefold increased risk for maternal death in women who received no prenatal care (Berg, 2010). Goldenberg and McClure (2018) have emphasized the importance of prenatal care to reduce stillbirth rates as well. In a study of almost 29 million births, the risk for preterm birth, stillbirth, early and late neonatal death, and infant death rose linearly with decreasing prenatal care utilization (Partridge, 2012). Similarly, from Parkland Hospital, Leveno and associates (2009) found that a significant decline in preterm births correlated closely with any use of prenatal care by medically indigent women. And in women with diabetes, adherence to prenatal care resulted in lower rates of neonatal admissions to the intensive care unit (Sperling, 2018a). Group prenatal care is acceptable and effective (American College of Obstetricians and Gynecologists, 2018g). Ickovics and coworkers (2016) compared this with individual prenatal care. Group care provided traditional pregnancy surveillance in a group setting with special focus on support, education, and active health-care participation. Women enrolled in group care had significantly better pregnancy outcomes. Carter and colleagues (2017) cited similar results. Childbirth education classes are also reported to result in better pregnancy outcomes (Afshar, 2017). Pregnancy in adolescents carries special risk, and guidelines have been developed that focus on this age group (Fleming, 2015). DIAGNOSIS OF PREGNANCY Pregnancy is usually identified when a woman presents with symptoms and possibly a positive home urine pregnancy test result. Typically, these women receive confirmatory testing of urine or blood for human chorionic gonadotropin (hCG). Further, presumptive signs or diagnostic findings of pregnancy may be found during the clinical examination. Sonography is often used, especially if miscarriage or ectopic pregnancy is a concern. Symptoms and Signs Amenorrhea in a healthy reproductive-aged woman who previously has experienced spontaneous, cyclical, predictable menses is highly suggestive of pregnancy. Menstrual cycles vary appreciably in length among women and even in the same woman (Chap. 5, p. 83). Thus, amenorrhea is not a reliable pregnancy indicator until 10 or more days have passed after expected menses. Occasionally, uterine bleeding that mimics menstruation is noted after conception. During the first month of pregnancy, these episodes are likely the consequence of blastocyst implantation. Still, first-trimester bleeding should prompt evaluation for an abnormal pregnancy. Of other symptoms, maternal perception of fetal movement depends on factors such as parity and habitus. In general, after a first successful pregnancy, a woman may first perceive fetal movements between 16 and 18 weeks’ gestation. A primigravida may not appreciate fetal movements until approximately 2 weeks later. At about 20 weeks, depending on maternal habitus, an examiner can begin to detect fetal movements. Of pregnancy signs, changes in the lower reproductive tract, uterus, and breasts develop early. Pregnancy Tests Detection of hCG in maternal blood and urine is the basis for endocrine assays of pregnancy. Syncytiotrophoblast produces hCG in amounts that increase exponentially during the first trimester. hCG and luteinizing hormone (LH) share the same receptor in tissues. Thus, a main function of hCG is to prevent involution of the corpus luteum, which is the principal site of progesterone formation during the first 6 weeks of pregnancy.  With a sensitive test, the hormone can be detected in maternal serum or urine by 8 to 9 days after ovulation. The doubling time of serum hCG concentration is 1.4 to 2.0 days. As shown in Figure 10-1, serum levels range widely and increase from the day of implantation. Lower levels of hCG rise more rapidly than higher levels (Barnhart, 2016). Peak hCG levels are reached at 60 to 70 days. Thereafter, the concentration declines slowly to a plateau at approximately 16 weeks’ gestation. FIGURE 10-1 Mean concentration (95% CI) of human chorionic gonadotropin (hCG) in serum of women throughout normal pregnancy. Measurement of hCG This hormone is a glycoprotein with high carbohydrate content. The general structure of hCG is a heterodimer composed of two dissimilar subunits, designated α and β, which are noncovalently linked. The α-subunit is identical to those of LH, follicle-stimulating hormone (FSH), and thyroid- stimulating hormone (TSH), but the β-subunit is structurally distinct. Thus, antibodies were developed with high specificity for the hCG β-subunit. This specificity allows its detection, and numerous commercial immunoassays are available for measuring serum and urine hCG levels. Each immunoassay detects a slightly different mixture of hCG variants, its free subunits, or its metabolites—however, all are appropriate for pregnancy testing (Braunstein, 2014). Depending on the assay used, the sensitivity for the laboratory detection limit of hCG in serum is 1.0 mIU/mL or even lower.  False-positive hCG test results are rare. A few women have circulating serum factors that may bind erroneously with the test antibody directed to hCG in a given assay. The most common factors are heterophilic antibodies. These are produced by an individual and bind to the animal-derived test antibodies used in a given immunoassay. Thus, women who have worked closely with animals are more likely to develop these antibodies, and alternative laboratory techniques are available (American College of Obstetricians and Gynecologists, 2017a). Elevated hCG levels may also reflect molar pregnancy and its associated neoplasms (Chap. 13, p. 238). Other rare causes of positive assays without pregnancy are (1) exogenous hCG injection used for weight loss, (2) renal failure with impaired hCG clearance, (3) physiological pituitary hCG, and (4) hCG-producing tumors that most commonly originate from gastrointestinal sites, ovary, bladder, or lung (McCash, 2017). Home Pregnancy Tests More than 60 different types of over-the-counter pregnancy test kits are available in the United States (Grenache, 2015). Unfortunately, many of these are not as accurate as advertised (Johnson, 2015). For example, Cole and associates (2011) found that a detection limit of 12.5 mIU/mL would be required to diagnose 95 percent of pregnancies at the time of missed menses. However, they reported that only one brand had this degree of sensitivity. Two other brands gave false-positive or invalid results. In fact, with an hCG concentration of 100 mIU/mL, clearly positive results were displayed by only 44 percent of brands. Accordingly, only approximately 15 percent of pregnancies could be diagnosed at the time of the missed menses. Some manufacturers of even newer home urine assays claim >99-percent accuracy for tests done on the day of—and some up to 4 days before—the expected day of menses. Again, careful analysis suggests that these assays are often not as sensitive as advertised. Sonographic Recognition of Pregnancy Transvaginal sonography is commonly used to accurately establish gestational age and confirm pregnancy location. A gestational sac is the first sonographic evidence of pregnancy, and it may be seen with transvaginal sonography by 4 to 5 weeks’ gestation. It should not be confused with a pseudogestational sac. The latter, or pseudosac, is a fluid collection within the endometrial cavity, which can occur in the setting of ectopic pregnancy (Fig. 12-3, p. 223). Further evaluation may be warranted if this is the only sonographic finding, particularly in a woman with pain or bleeding. A normal gestational sac implants eccentrically in the endometrium, whereas a pseudosac is seen in the midline of the endometrial cavity. Other potential indicators of early intrauterine pregnancy are an anechoic center surrounded by a single echogenic rim—the intradecidual sign—or two concentric echogenic rings surrounding the gestational sac—the double decidual sign (Fig. 10-2). If sonography yields equivocal findings, the term pregnancy of unknown location (PUL) is applied (Bobdiwala, 2019). In these cases, serial serum hCG levels and transvaginal sonography can help differentiate a normal intrauterine pregnancy from an extrauterine pregnancy or an early miscarriage (Chap. 12, p. 222). FIGURE 10-2 Transvaginal sonogram of a first-trimester intrauterine pregnancy. The double decidual sign is noted surrounding the gestational sac and is defined by the decidua parietalis (white asterisk) and the decidua capsularis (yellow asterisk). The arrow notes the yolk sac, and the crown-rump length of the embryo is marked with measuring calipers. (Reproduced with permission from Dr. Elysia Moschos.)  If the yolk sac—a brightly echogenic ring with an anechoic center—is seen within the gestational sac, an intrauterine location for the pregnancy is confirmed. The yolk sac can normally be seen by the middle of the fifth week. As shown in Figure 10-2, after 6 weeks, an embryo is seen as a linear structure immediately adjacent to the yolk sac. Cardiac motion is typically noted at this point. INITIAL PRENATAL EVALUATION Prenatal care is ideally initiated early. Major goals are to (1) define the health status of the mother and fetus, (2) estimate the gestational age, and (3) initiate a plan for continued obstetrical care. Typical components of the initial visit are summarized in Table 10-1. Subsequent care may range from relatively infrequent routine visits to prompt hospitalization because of serious maternal or fetal disease. TABLE 10-1. Typical Components of Routine Prenatal Care  Prenatal Record Use of a standardized record within a perinatal health-care system greatly aids antepartum and intrapartum management. Standardizing documentation allows communication and care continuity between providers and enables objective measures of care quality to be evaluated over time and across different clinical settings (Gregory, 2006). A prototype is provided by the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists (2017) in their Guidelines for Perinatal Care, 8th edition. Definitions Several definitions are pertinent to establishment of an accurate prenatal record. 1. Nulligravida—a woman who currently is not pregnant and has never been pregnant. 2. Gravida—a woman who currently is pregnant or has been in the past, irrespective of the pregnancy outcome. With the establishment of the first pregnancy, she becomes a primigravida, and with successive pregnancies, a multigravida. 3. Nullipara—a woman who has never completed a pregnancy beyond 20 weeks’ gestation. She may not have been pregnant or may have had a spontaneous or elective abortion(s) or an ectopic pregnancy. 4. Primipara—a woman who has been delivered only once of a fetus or fetuses born alive or dead with an estimated gestation duration of 20 or more weeks. In the past, a 500-g birthweight threshold was used to define parity. This threshold is now controversial. Namely, many states still use this weight to differentiate a stillborn fetus from an abortus, but the survival of neonates with birthweights 3 hours daily, lifting and carrying >5 kg, or physically exerting oneself at work. In a prospective study of more than 900 healthy nulliparas, women who worked had a fivefold higher risk of preeclampsia (Higgins, 2002). Thus, any occupation that subjects the gravida to severe physical strain should be avoided. Ideally, no work or play is continued to the extent that undue fatigue develops. Adequate periods of rest should be provided. Exercise In general, pregnant women do not need to limit exercise, provided they do not become excessively fatigued or risk injury (Davenport, 2016). Clapp and associates (2000) reported that both placental size and birthweight were significantly greater in women who exercised. Duncombe and coworkers (2006) reported similar findings in 148 women. In contrast, Magann and colleagues (2002) prospectively analyzed exercise behavior in 750 healthy women and found that working women who exercised had smaller neonates and more dysfunctional labors. The American College of Obstetricians and Gynecologists (2020a) advises a thorough clinical evaluation before recommending an exercise program. In the absence of contraindications listed in Table 10-6, pregnant women are encouraged to engage in regular, moderate-intensity physical activity for at least 150 minutes each week. Such activity has been shown to not adversely alter uterine artery Doppler studies (Szymanski, 2018). Each activity should be reviewed individually for its potential risk. Examples of safe activities are walking, running, swimming, stationary cycling, and low- impact aerobics. However, they should refrain from activities with a high risk of falling or abdominal trauma. Similarly, scuba diving is avoided because the fetus is at increased risk for decompression sickness (Reid, 2018). TABLE 10-6. Some Contraindications to Exercise During Pregnancy  In the setting of certain pregnancy complications, it is wise to abstain from exercise and even limit physical activity. Some women with pregnancy- associated hypertensive disorders, preterm labor, placenta previa, or severe cardiac or pulmonary disease may accrue advantages from being sedentary. Also, those with multiple or suspected growth-restricted fetuses may be served by greater rest. Seafood Consumption Fish are an excellent source of protein, are low in saturated fats, and contain omega-3 fatty acids. It is recommended that pregnant women ingest 8 to 12 ounces of fish weekly, but no more than 6 ounces of albacore or “white” tuna (U.S. Environmental Protection Agency, 2019). Because nearly all fish and shellfish contain trace amounts of mercury, pregnant and lactating women are advised to avoid specific types of fish with potentially high methylmercury levels. These include shark, swordfish, king mackerel, and tile fish. If the mercury content of locally caught fish is unknown, overall fish consumption should be limited to 6 ounces per week. Finally, to help avert listeriosis, eating raw or undercooked fish is avoided (American College of Obstetricians and Gynecologists, 2017j). Lead Screening Maternal lead exposure is associated with several adverse maternal and fetal outcomes across a range of maternal blood lead levels (Taylor, 2015). These include gestational hypertension, miscarriage, low birthweight, and neurodevelopmental impairments in exposed pregnancies. The levels at which these risks rise remains unclear. However, recognizing that such exposure remains a significant health issue for reproductive-aged women, the CDC (2010a) provides guidance for screening and managing exposed pregnant and lactating women. These guidelines, which have been endorsed by the American College of Obstetricians and Gynecologists (2018f), recommend blood lead testing only if a risk factor is identified. If the levels are >5 µg/dL, the lead source is sought and removed. Subsequent blood levels are obtained. Blood lead levels >45 µg/dL are consistent with lead poisoning, and women in this group may be candidates for chelation therapy. Affected pregnancies are best managed in consultation with lead poisoning treatment experts. National and state resources are available at the CDC website: www.cdc.gov/nceh/lead/. Automobile and Air Travel Pregnant women are encouraged to wear properly positioned three-point restraints as protection against automobile accident injury (Chap. 50, p. 892). The lap portion of the restraining belt is placed under the abdomen and across her upper thighs. The belt should be comfortably snug. The shoulder belt also is firmly positioned between the breasts. Airbags should not be disabled for the pregnant woman. In general, air travel in a properly pressurized aircraft has no harmful effect on pregnancy. Thus, in the absence of obstetrical or medical complications, the American College of Obstetricians and Gynecologists (2018a) has concluded that pregnant women can safely fly up to 36 weeks’ gestation. It is recommended that they observe the same precautions for air travel as the general population. Seatbelts are used while seated. Support stockings, periodic lower extremity movement, and at least hourly ambulation help lower the venous thromboembolism threat. Significant risks with travel, especially international travel, are infectious disease acquisition and development of complications remote from adequate health-care resources. Coitus In healthy pregnant women, sexual intercourse usually is not harmful. Whenever miscarriage, placenta previa, or preterm labor threatens, however, coitus is avoided. Nearly 10,000 women enrolled in a prospective investigation by the Vaginal Infection and Prematurity Study Group were interviewed regarding sexual activity (Read, 1993). They reported a decreased frequency of coitus with advancing gestation. By 36 weeks, 72 percent had intercourse less than once weekly. The decline is attributed to lower desire and fear of harming the pregnancy (Staruch, 2016). Intercourse specifically late in pregnancy is not harmful. Sayle and colleagues (2001) reported no increased—and actually a decreased—risk of delivery within 2 weeks of intercourse. Tan and associates (2007) studied women scheduled for nonurgent labor induction and found that spontaneous labor ensued at equal rates in groups either participating in or abstaining from intercourse. Oral-vaginal intercourse is occasionally hazardous. Aronson and Nelson (1967) described a fatal air embolism late in pregnancy as a result of air blown into the vagina during cunnilingus. Other near-fatal cases have been described (Bernhardt, 1988). Dental Care Examination of the teeth is included in the prenatal examination, and good dental hygiene is encouraged. Indeed, periodontal disease is linked to preterm labor. Unfortunately, although its treatment improves dental health, it does not prevent preterm birth (Daalderop, 2018). Dental caries are not aggravated by pregnancy. Importantly, pregnancy is not a contraindication to dental treatment including dental radiographs (American Academy of Pediatrics and American College of Obstetricians and Gynecologists, 2017). Immunization Current recommendations for immunization during pregnancy are summarized in Table 10-7. Well-publicized concerns regarding a causal link between childhood exposure to the thimerosal preservative in some vaccines and neuropsychological disorders have led some parents to vaccine prohibition. Although controversy continues, these associations have been proven groundless. Thus, many vaccines may be used in pregnancy (Munoz, 2019). The American College of Obstetricians and Gynecologists (2020c) stresses the importance of integrating an effective vaccine strategy into the care of both obstetrical and gynecological patients. The College further emphasizes that information on the safety of vaccines given during pregnancy is subject to change, and recommendations can be found on the CDC website at www.cdc.gov/vaccines. TABLE 10-7. Recommendations for Immunization During Pregnancy and Postpartum  Influenza and tetanus–diphtheria–acellular pertussis (Tdap) vaccinations are recommended routinely for all pregnant women (Munoz, 2019; Sperling, 2018b). Others are recommended for specific indications (see Table 10-7). Women who are susceptible to rubella should receive measles, mumps, and rubella (MMR) vaccination postpartum. This vaccine is contraindicated during pregnancy. Caffeine Whether adverse pregnancy outcomes are related to caffeine consumption is somewhat controversial. As summarized from Chapter 11 (p. 200), heavy intake of coffee each day—approximately five cups or 500 mg of caffeine— slightly raises the miscarriage risk. Studies of “moderate” intake—less than 200 mg daily—did not find a higher risk. It is unclear if caffeine consumption is associated with preterm birth or impaired fetal growth. Clausson and coworkers (2002) found no association between caffeine consumption 200 mg/d compared with those who consumed