First Trimester Pregnancy Screening Quiz

Fetal Movement and Growth Monitoring

• Regular fetal movement is crucial, defined as either four movements in one hour or ten movements in two hours.
• Fundal height should be monitored, as the uterus expands to twenty times its original size during pregnancy.
• Fetal heart tones can be assessed using a Doppler device.

Patient Education by Trimester

• Early Pregnancy Education:

  • Address common discomforts including nausea, vomiting, and swollen feet.
  • Emphasize the importance of prenatal vitamins and avoiding teratogenic substances.

• Late Pregnancy Education:

  • Discuss development of a birth plan and what to expect during labor and postpartum recovery.
  • For high-risk pregnancies, reinforce the need for hospital births for safety.

Routine Prenatal Care

• Essential assessments during each prenatal visit include vital signs, belly measurements, listening to fetal heart tones, and urinalysis.

Genetic Testing in Pregnancy

• Screening Tests:

  • Aim to identify risks for fetal abnormalities, including amniotic fluid index, biophysical profile, contraction stress test, daily fetal movement count, and multiple marker screening.

• Diagnostic Tests:

  • Focus on confirming specific abnormalities via procedures like amniocentesis and chorionic villus sampling.

Dating Pregnancy

• Pregnancy is calculated from the first day of the last menstrual period. The common formula involves subtracting three months, adding seven days, and adjusting the year if needed.
• Trimester classifications:
  • 1st trimester: First day to 14 completed weeks.
  • 2nd trimester: 15 weeks to 28 completed weeks.
  • 3rd trimester: 29 weeks to 40 completed weeks.
• Gestational milestones include:
  • 37 weeks - full term,
  • 42 weeks - past term.

Tests Performed During Pregnancy

• First Trimester:

  • Screenings: Nuchal translucency ultrasound.
  • Diagnostic: Chorionic villus sampling (earliest at 10 weeks).
  • Lab tests: Blood type, antibody screening, CBC, STI screenings.

• Second Trimester:

  • Screenings: Maternal serum alpha-fetoprotein, detailed anatomy ultrasound.
  • Diagnostic: Amniocentesis.
  • Lab tests: Glucose challenge test, Rhogam administration for RH-negative patients.

• Third Trimester:

  • Screenings: Ultrasound, amniotic fluid index, nonstress tests, etc.
  • Diagnostic: MRI exams as needed.
  • Lab tests: Group B strep screening, repeat CBC.

Indicators of Fetal Well-Being

• Doppler ultrasound assesses umbilical cord flow to check placenta perfusion.
• Vibroacoustic stimulation can help wake the fetus if heart rate accelerations are low.
• Diagnostic tests include amniocentesis for chromosomal analysis and ultrasound for pregnancy confirmation.

GTPAL Practice Scenarios

• Case 1: G4, T2, P1, A0, L3 (Three living children, with two born preterm).
• Case 2: G3, T1, P1, A1, L3 (Includes miscarriage and twins).
• Case 3: G3, T1, P1, A0, L3 (Twin pregnancy and term delivery).

Gene Mutations

• Recessive mutations require two copies (one from each parent); examples include:
  • Sickle cell anemia
  • Cystic fibrosis
  • Tay-Sachs disease
  • Phenylketonuria (PKU)
• Dominant mutations require only one copy; an example is Huntington's disease.
• Sex-linked gene mutations are associated with the X chromosome; notable examples include:
  • Hemophilia: females can be carriers with one X chromosome affected, while males express the condition with a single affected X.
  • Duchenne's muscular dystrophy.

Hormonal Changes in Pregnancy

• Estrogen, progesterone, and prolactin are crucial hormones during pregnancy's physiological changes.
• Vascular resistance decreases, leading to lower blood pressure.
• Symptoms may include:
  • Increased edema and respiratory capacity
  • Changes in breasts
  • Elevated likelihood of urinary tract infections (UTIs)
  • Gastrointestinal symptoms such as nausea, vomiting, and gassiness

Signs of Pregnancy

• Presumptive Signs (subjective):
  • Missed menstrual cycle (amenorrhea)
  • Breast changes (enlargement, tenderness)
  • Nausea and vomiting (common in the first trimester)
  • Frequent urination due to uterine pressure
  • Quickening (first fetal movements felt)
  • Fatigue prevalent in the first trimester
• Probable Signs (objective):
  • Uterine and abdominal growth
  • Melasma (skin pigmentation changes)
  • Linea nigra (dark skin line from umbilicus to pubis)
  • Darkening of nipples and areola
  • Ballottement test (fetal rebound upon cervix tapping)
  • Positive pregnancy test (hCG detection)
• Positive Signs (confirmatory):
  • Fetal heart tones via doppler (10-12 weeks)
  • Palpation of fetal movement (after 20 weeks)
  • Sonogram visualization (cardiac motion can be seen as early as 4-8 weeks)

Dating Pregnancy

• Dating calculated from the first day of the last menstrual period (LMP), modified by subtracting three months, adding seven days, and adjusting the year.
• Trimester breakdown:
  • First trimester: Up to 14 completed weeks
  • Second trimester: 15-28 completed weeks
  • Third trimester: 29-40 completed weeks
• Key gestational milestones:
  • Full term begins at 37 weeks and ends before 42 weeks
  • Nonviable below 20 weeks, preterm between 20 to 36 weeks.

Prenatal Testing by Trimester

• First Trimester:
  • Screenings: Nuchal translucency ultrasound, technologies to scan for abnormalities
  • Diagnostic: Chorionic villus sampling (from 10 weeks)
  • Labs include blood type, CBC, STI screenings, and Cell-free DNA tests.
• Second Trimester:
  • Screenings: Maternal serum alpha fetoprotein, anatomy scan at 20 weeks
  • Diagnostics: Amniocentesis
  • Labs: Glucose challenge test, repeat CBC, Rhogam for Rh-negative moms.
• Third Trimester:
  • Screenings: Ultrasound, Amniotic Fluid Index, Nonstress test, Contraction stress test
  • Diagnostics: MRI
  • Labs: Group B strep screening and infrequent STI retesting.

Indicators of Fetal Well-being

• Regular fetal movement is a sign of well-being, typically measured by counts (4 movements in 1 hour, or 10 in 2 hours).
• Fundal height measurement indicates growth; a pregnant uterus is significantly larger than its non-pregnant state.
• Auscultation of fetal heart tones ensures fetal health and rhythmicity.

Patient Education Priorities

• Early pregnancy education focuses on normal discomforts and healthy habits such as nutrition, weight gain, and teratogen avoidance.
• Labor-related education includes birth plans, postpartum recovery, and hospital versus home birth considerations for high-risk conditions.

Routine Prenatal Care

• Standard checks include monitoring vital signs, abdominal measurements, auscultating fetal heart tones, and conducting urinalysis.

Diagnostic vs. Screening Tests in Pregnancy

• Screening tests: Identify risks for abnormalities; examples include:
  • Daily fetal movement count, nuchal translucency, and multiple marker screening assessing hormone levels.
• Diagnostic tests: Confirm or identify specific abnormalities:
  • Amniocentesis and chorionic villus sampling to check for chromosomal issues.
  • MRI for confirming structural abnormalities, with procedures often associated with higher risk.

GTPAL Practice

• GTPAL code provides an overview of pregnancy history:
  • G refers to total number of pregnancies.
  • T denotes term births (37 weeks or more).
  • P indicates preterm births (20-36 weeks).
  • A stands for miscarriages or abortions (spontaneous or elective).
  • L represents living children.
• Various examples illustrate the encoding of pregnancy histories based on GTPAL.

Test your knowledge on laboratory tests and screening procedures commonly performed during the first trimester of pregnancy. This quiz covers essential topics such as nuchal translucency ultrasound and fetal well-being assessments. Brush up on patient education and diagnostic tests relevant to early prenatal care.