Bleeding in Pregnancy: Placenta Previa, Abruptio, Vasa Previa, Uterine Rupture (OB2 - PDF)

OB2 OBSTETRICS 2 Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine TRANS 6...

OB2 OBSTETRICS 2 Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine TRANS 6 Rupture) MODULE 3 Floriza C. Salvador, MD, FPOGS, FPSUOG August 8, 2024 LECTURE OUTLINE I. OBSTETRIC HEMORRHAGE I Obstetric Hemorrhage One of the top 3 causes of maternal deaths worldwide, more frequently, the single most common cause of maternal mortality in II Uterine Rupture developing countries and underdeveloped countries A. Pathogenesis 3 Most Common Hemorrhages in the 2nd Half of Pregnancy III Predisposing Factors A. Antepartum 1 Uterine Rupture B. Acquired 2 Abruptio Placenta IV Diagnosis A. High Index of Suspicion 3 Placenta Previa B. Non-Reassuring Fetal Heart Rate Pattern C. Loss of Uterine Contraction CASE D. Feto-Maternal Compromise 32 years old, G2P1 (1001) 1 V Management A. Laparotomy Chief Complaint B. Repair/Hysterectomy Labor pains C. Replacement of Blood Loss History of Present Pregnancy / Prenatal History VI Abruptio Placenta A. Definition 39 weeks AOG B. Classification Obstetrical History 1. Complete/Total 2. Partial Previous CS 1 year ago C. Types of hemorrhage Physical Examination D. Pathology E. Severity of Abruptio Vital Signs: F. Risk factors ○ BP: 110/80 mmHg G. Signs and symptoms ○ FHT: 140 bpm H. Diagnosis and diagnostics Internal Examination: I. Complications ○ Fully dilated, fully effaced, cephalic, Station +4, (-) BOW J. Management After some time, the patient felt a severe abdominal pain. K. Case discussion ○ BP: 60 mmHg palpatory ○ FHT: Not appreciated VII Placenta Previa ○ Minimal-to-moderate bleeding per vagina A. Definition B. Classification 1. Placenta Previa II. UTERINE RUPTURE 2. Low lying When there is a uterine rupture, there is a break in the uterine C. Pathology wall. D. Risk Factors E. Clinical features CLASSIFICATION BASED ON THE ANATOMIC LAYERS F. Diagnosis G. Management 1 Partial VIII Vasa Previa Visceral peritoneum is intact A. Definition Uterine dehiscence: B. Classifications ○ Outermost layer remains intact; innermost layer C. Risk factors (endometrium and myometrium) separates D. Diagnosis Ultrasound reveals that the defect in the entire placental thickness E. Management is seen in the area of the CS scar ○ May be detected during prenatal surveillance LECTURE OBJECTIVES ○ If seen, one would notice: 1. Diagnose correctly the common obstetric hemorrhages in the A defect in the surface of the uterine wall second half of pregnancy A depression 2. Correlate the different sonographic features with diagnosis A discoloration of the lesion 3. Describe briefly the pathophysiology of each condition 2 Complete 4. Identify the risk factors associated in the development of these conditions Involves ALL layers 5. Formulate an acceptable management plan for each condition Observed when all three layers separate, including the visceral among Pregnant Patients peritoneum 🧠 Must Know 📖 Book 📝 Previous Trans Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 1 of 14  Figure 1. Partial Uterine Rupture Sonographic and Laparoscopic findings Figure 5. Primary Type of Uterine Rupture Dr. Salvador’s Online Lecture Video Source: Online Video Lecture 2. SECONDARY DELIVERY There is already an existing previous scar or incision on the uterine wall or an injury or a congenital anomaly of the uterus. On examination, you will see the fetal part maybe out of the uterus like the lower or upper extremity, the fetal head, and sometimes the whole fetus together with the intact fetal membranes are extruded out into the abdominal cavity. Figure 2. Partial Uterine Rupture Dr. Salvador’s Online Lecture Video Figure 6. Secondary Type of Uterine Rupture Source: Online Video Lecture Figure 3. Complete Uterine Rupture Dr. Salvador’s Online Lecture Video A. PATHOGENESIS Uterine rupture is brought about by 1 Thinness of the uterine wall due to prolonged labor 2 External factors like uterotonics 3 Presence of a scar The break will either involve the entire thickness of the entire uterine wall (endometrium, myometrium and serosa) or it will only involve the inner two layers of the uterine wall. This brings us to another type of classification: Figure 7. Secondary Type of Uterine Rupture. ○ Primary Dr. Salvador’s Online Lecture Video. ○ Secondary III. PREDISPOSING FACTORS It is important to note these in the history because they will be your clue in the diagnosis of uterine rupture. The risk factors are divided into two: ○ Antepartum ○ Acquired ○ Intrapartum (will be under a different topic) A. ANTEPARTUM Usually, there is surgery involving the myometrium. 1. SURGERY INVOLVING THE MYOMETRIUM Figure 4. Pathogenesis of Uterine Rupture Source: Online Video Lecture 1 Cesarean delivery 1. PRIMARY TYPE OF UTERINE RUPTURE 2 Previous repair of the uterine rupture Conditions like dystocic labor or fundal pressure were applied over 3 Deep cornual resection of interstitial ectopic the uterus. The rent might be along the lateral aspect of the corpus or it may 4 Metroplasty extend to the cervix or even the bladder. 5 Hysteroscopic procedure The rent may happen along the anterior or posterior wall, or it may extend longitudinally or upward towards the fundus or towards the 6 Myomectomy entry of the uterine arteries. Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 2 of 14  CESAREAN DELIVERY The scar may not be adequately repaired or the patient underwent prolonged labor before consultation was made. For our case: ○ In the history, it can be recalled that there was a prior cesarean section. ○ Another important data in the history: Interval of the first pregnancy to the present ○ The previous pregnancy is less than 18 months or to be exact is one year only. The integrity of the scar at this time may be questionable. TWO TYPES OF CESAREAN SECTION Figure 10. Types of Ectopic Pregnancy Source: Online Video Lecture CLASSICAL (Encircled green) shows Cornual Ectopic Pregnancy. The incision is longitudinal, located at the corpus. The procedure is to remove the ectopic to make a deep incision involving the Corpus is a thick muscular structure that can contract. myometrium near the lumen of the fallopian tube inside the uterine cavity. Once the patient have contractions, this scar has a strong This will create a scar that may be prone to rupture. tendency to separate. METROPLASTY LOW TRANSVERSE It is done to the uterus with a congenital anomaly The incision is located at the lower uterine segment. Lesser tendency to rupture In a non-pregnant uterus, the isthmus is the counterpart of the lower uterine segment, a non-muscular portion of the uterus that has a lower tendency to rupture. Figure 11. Metroplasty of Bicornuate Uterus with Left & Right Hemi-cornum Source: Online Video Lecture Figure 8. Uterine Dehiscence of a Previous CS Scar (Lower photo) shows the uterus after repair / metroplasty with scars and Source: Online Video Lecture adhesions marking the previous incisions also prone to rupture. Case of a previous C-section which, upon opening up, revealed a glistening membrane on the area of the CS scar HYSTEROSCOPY REPAIR OF PREVIOUS UTERINE RUPTURE It is done to visualize the inner uterine cavity wherein there is a resection or removal of endometrial polyp (submucous myoma) Uterine Dehiscence or Rupture of a previous CS with a repair has When a portion of the myometrium is included during the a greater chance of a repeat rupture resection, this may also create a weakness in the uterine wall. Occurs about 1-2 weeks early of the previous event This is performed transvaginally. Figure 12. Hysteroscopy Source: Online Video Lecture Figure 9. Rupture of a previous uterine rupture Source: Online Video Lecture 2. COINCIDENTAL TRAUMA 1 Abortion with Curettage Beyond Myometrium DEEP CORNUAL RESECTION OF INTERSTITIAL ECTOPIC PREGNANCY 2 Vehicular Trauma TYPES OF ECTOPIC PREGNANCY ABORTION WITH CURETTAGE BEYOND MYOMETRIUM 1 Ampulla Ectopic Pregnancy The same condition may be applied with hysteroscopy. 2 Cervical Ectopic Pregnancy A portion of the myometrial layer may be included during the curettage. 3 Cornual/Interstitial Ectopic Pregnancy VEHICULAR TRAUMA 4 Ovarian Ectopic Pregnancy One would note in the history that the patient figured in the vehicular accident. The contrecoup mechanism of the trauma may be applicable to the patient wherein the rupture may occur at the posterior uterine wall. Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 3 of 14  Figure 16. Myoma Uteri Source: Online Video Lecture - Salvador Uterine Rupture Final (1) Figure 13. Vehicular Trauma Source: Online Video Lecture - Salvador Uterine Rupture Final (1) IV. DIAGNOSIS 3. CONGENITAL A. HIGH INDEX OF SUSPICION A high index of suspicion based on a good clinical history about Pregnancy may develop in the unprepared congenital lesions like previous delivery and uterine operations strongly points to the the unicornuate uterus and rudimentary horn but pregnancy here development of uterine rupture. cannot be supported during the advancing gestation and will most likely resort in uterine rupture even in the early gestation. CASE 1 32 years old, G2P1 (1001) CONT'D Physical Examination The patient felt a severe pain again. A repeat IE revealed the absence of presenting part. From the station +4, the presenting part becomes floating or cannot be digitally examined. The fetus with the uterine contents may be totally or partially Figure 14. Pregnancy in the unicornuate uterus (Left); Pregnancy in the extruded out in the abdominal cavity. rudimentary horn (Right) Source: Online Video Lecture - Salvador Uterine Rupture Final (1) B. ACQUIRED 1 Accrete Syndromes 2 Presence of Large Myoma 3 Gestational Trophoblastic Neoplasia 1. ACCRETE SYNDROME Also known as “Morbidly Adherent Placenta” Placenta has developed beyond the myometrium, up to or beyond Figure 17. IE revealing absence of presenting part (blue arrow) the serosa. Source: Online Video Lecture - Salvador Uterine Rupture Final (1) Sonographically diagnosed by some distinct features: ○ Presence of vascularities overlying the placenta B. NON-REASSURING FETAL HEART RATE PATTERN ○ In the scan there are a lot of colors which represent the During cardiotocogram, there will be signs of fetal distress. arteries and veins A non-reassuring fetal heart rate pattern may be recognized. ○ The uterus will present with prominent vessels in a thinned out Initially, from a normal heart rate of 120-160 bpm to severe fetal area with the placenta underneath heart rate deceleration pattern may be present which gradually may transform into a prolonged bradycardia, then finally undetectable heart rate. C. LOSS OF UTERINE CONTRACTION There will be cessation of uterine contractions (seen in the leftmost arrow). Figure 15. Accrete Syndrome ○ The uterus cannot be anymore palpated abdominally. Source: Online Video Lecture - Salvador Uterine Rupture Final (1) 2. VERY LARGE MYOMA Also known as “Myoma Uteri” Myoma does not go along myometrial contractions. The interface of the junction of the myoma in a normal myometrium creates a difference in the tension. Rupture may happen even in antepartum or during labor. Figure 18. ECG showing bradycardia (HR: 60 bpm) Source: Online Video Lecture - Salvador Uterine Rupture Final (1) Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 4 of 14 D. FETO-MATERNAL COMPROMISE Physical Examination Before, the occurrence of circulatory collapse in a gravid patient, Abdominal Findings: maternal tachycardia and hypovolemia will be noted even if ○ (+) tenderness there is no bleeding in the vagina. ○ strong contractions q 1-2 min ○ Due to the hemorrhage that will occur within the abdominal Internal Examination: cavity ○ Cervix is soft, 1-2 cm dilated, 50% effaced, ○ Otherwise the condition may present with profuse vaginal ○ Cephalic, (+) BOW bleeding ○ Station 0 with no bleeding The outcome of the baby is usually not good ○ There is an increase in perinatal morbidity or mortality ○ Sometimes if the fetus survives, there might be a neurological A. DEFINITION deficit due to prolonged hypoxia Premature separation of the placenta from its normal implantation before the delivery of the fetus ○ Partial or complete ○ Sudden [BATCH 2025] INFORMATION Anat and coworkers (2016) have defined severe placental abruption as ○ Maternal sequelae that include disseminated intravascular coagulation (DIC, shock, transfusion, hysterectomy, renal failure or death) ○ Fetal complications such as non reassuring fetal status, growth restriction, death ○ Neonatal outcomes that include death, preterm delivery or growth restrictions Figure 19. Feto-maternal compromise Lifted from Williams 26th ed Source: Online Video Lecture - Salvador Uterine Rupture Final (1) V. MANAGEMENT B. CLASSIFICATION Complete/Total: entire placenta is separated A. LAPAROTOMY Partial: portion or some of the cotyledons are detached Immediate laparotomy or opening the abdomen requires a very quick decision to deliver the baby once uterine rupture is recognized and should be less than 17 minutes. B. REPAIR/HYSTERECTOMY For uterine preservation of patients with low parity or who are young ○ If the rupture can be repairable once the degree of rupture has been assessed, do hysterorrhaphy. Hysterectomy can be done for multigravidas if the patient has already completed her reproductive career. C. REPLACEMENT OF BLOOD LOSS Correction of anemia due to acute blood loss by blood transfusion Figure 20. Partial and Complete Abruptio Placenta of necessary blood components is always a part of the Source: Online Video Lecture - Salvador Abruptio Placenta management. [BATCH 2025] INFORMATION SUMMARY Traumatic abruption Good Clinical History and PE ○ External trauma from motor vehicle crashes or aggravated ○ Must be done with good history taking and complete physical assault examination ○ Can also stem from minor trauma High Index of Suspicion ○ Clinical presentation and consequences differ from ○ With support from sonography and other ancillary procedure spontaneous cases (e.g. cardiotocogram) may be requested Chronic Abruption Immediate decision to refer ○ When placental separation is not followed by delivery ○ The immediate decision to deliver the fetus must be taken ○ Some cases begin in early pregnancy into consideration to save the baby and mother from an ○ Possibly due to abnormally elevated maternal serum adverse outcome. aneuploidy markers and subsequent abruption ○ It is important to know the predisposing factors and have ○ Some develop chronic abruption- oligohydramnios sequence the proper timing to refer the patient to a specialist. ○ Later in pregnancy, hemorrhage with retroplacental hematoma formation is occasionally arrested completely VI. ABRUPTIO PLACENTA without delivery due to abnormal levels of MSAFP or The incidence of abruptio placenta remains the same despite the placenta-specific RNA decrease of fetal deaths from all other causes Lifted from Williams 26th ed Perinatal mortality rate of abruptio placenta is higher than combined perinatal rates in the general population CASE 24 years old, G1P0 (Full Term) 2 Chief Complaint Severe hypogastric pain Vitals 170/110 mmHg, FHT - not appreciated Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 5 of 14 C. TYPES OF HEMORRHAGE F. RISK FACTORS External: Blood is extruded out of the uterus or the vagina It is important to know the risk factors present in the patient. This Concealed: Blood is retained within the placental plane and might give a look on the working impression uterine wall ○ Seen less commonly 1 Prior abruptio History of prior abruption might serve as a guide Occurs 1-3 weeks early in the first abruption 2 Increased parity and maternal age Increased parity ○ Abruptio placenta is more likely experienced in older women than in younger women 3 Preeclampsia Increased pressure is noted in the inferior trophoblastic invasion. “Spiral arteries elicit medial layer contractions” 4 Chronic Hypertension There is greater risk due to reduced intravascular fluid Figure 21. Different types of hemorrhages volume on top of hypertension. Source: Online Video Lecture - Salvador Abruptio Placenta 5 Chorioamnionitis Inflammation or infection leads to weakened membranes D. PATHOLOGY 6 Preterm rupture of membranes Initiated by the rupture of spiral artery to cause hemorrhage into: Tensile strength of the membranes is decreased 1 Decidua basalis 7 Multiple gestation The principles of uterine stretch lead to activation of 2 Formation of retroplacental clot (hematoma) contraction associated proteins (CAP) 3 Separates decidua basalis from myometrium (happens at This may lead to uterine activation and cervical ripening periphery or central portion of placenta) 8 Low birthweight 4 Retroplacental hematoma compresses placental plate 9 Polyhydramnios Principles of uterine stretch are also applied 10 Cigarette smoking Known association but unknown mechanism ○ Probably due to decreased placental blood Figure 22. Pathogenesis of abruptio placenta Nicotine Source: Online Video Lecture - Salvador Abruptio Placenta ○ Vasoconstrictive effects on uterine and umbilical arteries ○ Impedes oxygenation by its influence on elevating carboxyhemoglobin concentration ○ Development of micro infarctions in the placenta result to thrombus or necrotic foci formation ○ In 2008, Kanitzky et al showed evidences of hypoxia Figure 23. Summary of pathogenesis of abruptio placenta such as fibrin and thrombus Source: Online Video Lecture - Salvador Abruptio Placenta 11 Cocaine use E. SEVERITY OF ABRUPTIO 12 Presence of myoma In 2019, Smith has proposed various classifications of abruptio placenta based on severity. G. SIGNS AND SYMPTOMS Table 1. Severity of Abruptio Sudden onset of abdominal pain FINDING CLASS CLASSIFICATION ○ Not compatible with the late stage of labor ○ On examination, uterine contractions are tetanic and very 1. Discovery of blood clot strong 0 Asymptomatic 2. Diagnosis is made retrospectively ○ They do not attain the baseline non-conducting state Uterine tenderness 1. No sign or small amount of vaginal ○ Tenderness upon palpation of the abdomen bleeding ○ Internal examination usually presents early dilatation findings 2. Slight uterine tenderness 1 Mild Non-reassuring fetal status 3. Maternal BP and HR are normal ○ Fetus may be tachycardic and/or extremely bradycardic 4. No signs of fetal distress Hypertonic uterine contraction 1. No sign or with a moderate amount Vaginal bleeding of vaginal bleeding ○ Patient may appear pale, representing circulatory 2. Significant uterine tenderness with compromised tetanic contractions 2 Moderate 3. Maternal BP and HR are normal H. DIAGNOSIS AND DIAGNOSTICS 4. Evidence of fetal distress Diagnosis for a severe type of abruption is not difficult 5. Hypofibrinogenemia Presence of sudden abdominal pain, uterine tenderness, and 1. No sign to heavy amount of vaginal board-like rigidity of the abdomen are common bleeding Frequent uterine contraction, non-reassuring fetal status, or fetal 2. Tetanic contraction or board-like distress may also be present rigidity of the abdomen Profuse vaginal bleeding is common to others, but in instances of 3 Severe mild abruption with minimal symptoms, the diagnosis is by 3. Maternal hypovolemic shock 4. Hypofibrinogenemia and exclusion coagulopathy 5. Fetal death Source: Online Video Lecture - Salvador Abruptio Placenta Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 6 of 14  Figure 24. Placental Abruption Source: Online Video Lecture - Salvador Abruptio Placenta Figure 27. A recently delivered placenta wherein there is still attached retroplacental clot (C: blue circle) on the maternal side of the placenta Source: Online Video Lecture - Salvador Abruptio Placenta 1. DIAGNOSTIC MODALITIES 1 Ultrasound – limited I. COMPLICATIONS Limited: What would like to search in the ultrasound Look for the thickened area or hypoechoic area in the 1 Consumptive Coagulopathy placenta which may represent the retroplacental clot Sonographic findings: 2 End Organ Failure ○ Thicker placenta 3 Couvelaire Uterus ○ Hypoechoic areas 4 Hypovolemic Shock 2 Fibrinogen levels (301-696 mg/dl) – late Lower amount as low as 150-250 mg/dl Normal value in the third trimester: 300-600 mg/dl 1. CONSUMPTIVE COAGULOPATHY Could also be a late finding Since there is a release of thromboplastin into the maternal circulation, one of the complications is consumptive coagulopathy 3 D dimers Causes consumption of procoagulant factors, leading to the May also confirm abruptio placenta activation of the clotting 4 Cardiotocography — late Increase levels of D-dimers Able to appreciate the non-reassuring fetal heart rate pattern Decrease levels of fibrinogen or higher levels of fibrinogen such as tachycardia or bradycardia products 5 CBC, Blood Typing, Prothrombin time, Activated partial 2. END ORGAN FAILURE thromboplastin time, and other blood parameters Acute Kidney Injury (AKI) ○ Due to severe hypotension, wherein the blood supply to the important organs are compromised Sheehan syndrome ○ Hypoperfusion of the pituitary ○ Loss of axillary and pubic hair ○ Difficulty to breastfeed ○ Episodes of oligomenorrhea to amenorrhea ○ Weight gain 3. COUVELAIRE UTERUS Uterus is visualized with a seepage of extravasated blood into the myometrium, fallopian tubes, ovaries, and broad ligament serosa Not an indication to do hysterectomy Figure 25. Ultrasound of a recent abruption in which a thicker placenta can be seen. The darker area than the usual encircled (yellow circle) part is called the hypoechoic area which may represent the retroplacental hematoma Source: Online Video Lecture - Salvador Abruptio Placenta Figure 27. Couvelaire uterus (left) and Abruptio placenta (right) Source: Online Video Lecture - Salvador Abruptio Placenta 4. HYPOVOLEMIC SHOCK If severe enough it will cause maternal and fetal mortality J. MANAGEMENT Depends on: ○ How advance the labor is ○ Age of gestation Figure 26. Cardiotocogram findings which show the result of the fetus showing ○ Maternal Indication bradycardia and even the loss of the fetal heart rate ○ Fetal Indication Source: Online Video Lecture - Salvador Abruptio Placenta Whether there is compromise or not Whether the pregnancy can be prolonged Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 7 of 14  1 Early Amniotomy SUMMARY Abruptio placenta 2 Immediate delivery ○ Premature separation of placenta that is normally implanted 3 Replacement of blood loss before the deliver of the fetus ○ Classification: 4 Prevent other complications Complete/Total Partial 1. EARLY AMNIOTOMY ○ Type of Hemorrhage When seen early, this procedure has always championed the initial External management of placental abruption Concealed Advantages: ○ Pathogenesis: Rupture of spinal artery → hemorrhage into ○ Decreases the intrauterine pressure decidua basalis → formation of retroplacental clot ○ Better spiral artery compression, useful decrease in (hematoma) → separated decidua basalis from myometrium implantation site bleeding (at periphery or central portion of placenta) → retroplacental ○ There is membrane rupture which may hasten delivery hematoma compresses placental plate ○ Achieves better uterine contraction ○ Reduces thromboplastin release into the maternal circulation VII. PLACENTA PREVIA Before the advent of sonography, the diagnosis of placenta previa 2. IMMEDIATE DELIVERY was suspected among patients with vaginal bleeding. As consequent finding, a placenta during actual internal Fetus is still alive Immediate delivery should be done examination leading to torrential blood loss and greater risk of Early labor Cesarean might be done maternal and fetal death Others practice a double set-up, wherein: Cases of possible ○ The patient is set-up at the operating room and will undergo an May wait for vaginal delivery imminent delivery internal examination. ○ If it turns out that the patient has previa = cesarean section In case of a non-viable May wait for vaginal delivery, will push through fetus (or not alive) especially when the mother is stable CASE 3. REPLACEMENT OF BLOOD LOSS 35 years old, G2P1 (32 wks AOG) 3 Can be done by using plasma expanders Chief Complaint 4. PREVENT OTHER COMPLICATIONS Vaginal spotting (bleeding noted upon waking up) There is prevention of complications (initiated by the hypoperfusion or the hypovolemia of the patient) to avoid injuries to the important History organs of the patient Only 1 prenatal checkup during 1st trimester Smoker, 1-2 sticks/day K. CASE DISCUSSION Previous CS (1st pregnancy) Vitals CASE 24 years old, G1P0 (Full Term) Normal, FHT = 150 bpm 2 Chief Complaint Physical Examination Severe hypogastric pain No uterine contractions Cardiotocogram: Vitals ○ (-) Deceleration ○ (-) Contractions 170/110 mmHg, FHT - not appreciated ○ (+) Acceleration Physical Examination Ultrasound: ○ Placenta previa Abdominal Findings: ○ (+) tenderness ○ strong contractions- 1-2 min A. DEFINITION Internal Examination: Placenta previa is when the placenta is implanted in the lower ○ Cervix is soft, 1-2 cm dilated, 50% effaced, uterine segment, over or very near the internal cervical os ○ Cephalic, (+) BOW ○ The lower uterine segment is the isthmus part of the corpus ○ Station 0 with no bleeding during the non-pregnant state. ○ It has expanded to about 4 to 5 cm nearing the 3rd trimester Management B. CLASSIFICATION Amniotomy ○ Since it is 1-2 cm dilated and it is unknown whether the fetal The first variant covers and crosses the heart tone can be appreciated internal os completely. ○ To release uterine pressure Placenta 1 The second variant is that the placental ○ Note the character of the amniotic fluid Previa edge partially encroaches the internal os Clear: baby has not yet passed out meconium; baby without crossing it. might be okay Stained/Blood-tinged: because of the retroplacental Implantation lies within the 2cm wide clot admixed with amniotic fluid perimeter around the internal os. ○ Real status of the baby may be appreciated once pressure is The placental edge is within 2 cm from the released internal os but does not cross over it. With a fetal heart tone? Or none? This condition may change in a 1 cm dilated ○ If there is a fetal heart tone, since this is only 1-2 cm, perform 2 Low Lying cervix becoming 5 cm in dilatation. a cesarean section The placental edge now becomes partially ○ If it is 9 or 10 cm dilation, station +3 , await vaginal delivery attached and is now transformed into a partial With 170/110 mmHg blood pressure, give Anti-hypertensive + placenta previa. magnesium sulfate Anatomical relationships are not precise as the pregnancy advances even during labor. Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 8 of 14  E. CLINICAL FEATURES Painless The most important feature of placenta previa 1 vaginal Painless and usually begins without any warning bleeding Occurring without contractions May not be profuse Other pregnancies have no bleeding throughout the prenatal until labor begins. Sentinel The internal os dilates and some portion of the 2 bleed placenta separates. Since the lower uterine is a non-contracting Figure 28. (L) Placenta Previa covers the internal os completely, (M) Placenta segment, bleeding is poorly controlled, hence Previa only covers it partially (R) Low lying type of placenta further bleeding continues. Source: Online Video Lecture - Salvador Placenta Previa 3 Occurs late in 2nd trimester or later gestation C. PATHOLOGY 4 Slight or profuse From the latin word “previa” = going before Technically, placenta previa when it bleeds is the premature separation of an abnormally planted placenta. F. DIAGNOSIS ○ The placenta or a portion of it becomes the presenting part. In any vaginal bleeding, after mid-pregnancy, always consider Early in pregnancy, implantation of the zygote in the first location placenta previa with good blood supply and oxygenation in the decidua basalis. A digital examination is not allowed in placenta previa Unfavorable conditions allow the zygote with the developing trophoblast to implant elsewhere. Thus, development of placenta Transabdominal For stable patients 1 previa. scan Requested for placenta localization Gold standard PLACENTAL MIGRATION Transvaginal 2 Resort to this if placental edge is still not scan Normally, the growth is towards the fundus where there is a good visualized source of blood supply called Trophotropism. If available in hospital/institution In some cases, placenta growth is favored at the Lower Uterine 3 Color Doppler May be more helpful Segment (LUS). Placental edge is initially assessed to be covering the internal os NOTE: To label a case of placenta previa, the uterus must have but after a repeat scan at around 35 weeks it can show an developed a lower uterine segment, usually at around 28 weeks of absence of encroachment called placental migration gestation. The placenta or a portion of it becomes the presenting ○ Actually is a misnomer. part. ○ Widening of the LUS towards end of the third trimester wherein the placenta lies close to the placental edge but actually not over the internal os. D. RISK FACTORS Advanced maternal age confounded with Maternal 1 conditions like altered hormonal or implantation age environments Higher parity and probability having several 2 Multiparity uterine procedures (i.e. curettage, infertility workup) Nicotine and carbon monoxide act as Cigarette 3 vasoconstrictors of placental vessels thereby smoking decreasing the oxygenation capacity. Environment with decreased oxygenation so Figure 29. Placenta with a normal occasion. 4 Leiomyoma that it bumps off the zygote or the blastocysts Source: Online Video Lecture - Salvador Placenta Previa to other implantation sites Placenta (green line). Distance of placenta to internal os (red line). Internal os (yellow line). Prior At times, the lower uterine segment may 5 cesarean provide an area with rich vascular supply since delivery the LUS is near the uterine arteries. Inflammatory mediators and oxidative stress may bring about effective decidualization of Assisted placental vessels and uterine contractions 6 reproductive caused by the pelvic additions of technology endometriosis which may be associated with placenta previa. Figure 30. Sonographic features of placenta previa. Source: Online Video Lecture - Salvador Placenta Previa Cervical canal (red line). Placenta edge (yellow line), showing that the placental edge crosses over the internal os. Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 9 of 14  Physical Examination No uterine contractions (painless) Cardiotocogram: ○ (-) Deceleration ○ (-) Contractions ○ (+) Acceleration Ultrasound: ○ Placenta previa Management Cesarean section VIII. VASA PREVIA Figure 31. Diagnosis of Placenta Previa by Ultrasound with color flow mapping. CASE Source: Online Video Lecture - Salvador Placenta Previa 28 years old, G1, Full term 4 Chief Complaint Labor pains Vitals FHT - 140 bpm Physical Examination Internal Examination: ○ 8cm dilated, fully effaced, Cephalic, Station +1, (+) BOW Other pertinent findings: ○ Amniotomy was done revealing clear amniotic fluid which later became blood streaked ○ Repeat fetal heart tone = 0 ○ She later delivered to a pale, fresh still birth fetus Figure 32. Placental Tissue under the speculum examination. Cause of Death Source: Online Video Lecture - Salvador Placenta Previa In this condition, the baby died of exsanguination. NOTE: Once it is known that there is a placenta previa, no internal Further examination revealed that vessels are attached to the examination must be done. Speculum examination may be done to membranes and overlying the cervical os. possibly visualize the placental tissue. ○ The vessels can be torn during spontaneous rupture of membranes or during artificial amniotomy. G. MANAGEMENT Mode of delivery is always Caesarian section. A. DEFINITION Allow to reach the period of viability 1 Vessels run along the membranes overlying internal os ○ For pregnancy before the period of viability, it has to be temporized 2 After rupture or amniotomy 3 Fetal exsanguination 1 Tocolytics To control preterm labor 2 Corticosteroids To hasten lung maturity 3 Bed rest may also be advised 4 Cesarean delivery Always the mode of delivery Done if the bleeding compromises the mother in instances wherein the bleeding 5 CS-hysterectomy is still profuse after the delivery of the placenta Correction of May be done even before the delivery 6 blood loss or Units of blood should be ready during the anemia actual placenta previa operation H. CASE DISCUSSION Figure 33. Vasa Previa Source: Online Video Lecture - Salvador Vasa Previa CASE 35 years old, G2P1 (32 wks AOG) 3 Chief Complaint Vaginal bleeding (bleeding noted upon waking up - sentinel bleed, manifested during rest) History Only 1 prenatal checkup during 1st trimester Smoker, 1-2 sticks/day Previous CS (1st pregnancy) Vitals Normal, FHT = 150 bpm Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 10 of 14 B. CLASSIFICATIONS IX. APA REFERENCES Dr. Fortun, V.L. (2024). Abruptio Placenta Lecture Video. Moodle. TYPE 1 TYPE 2 Dr. Salvador, F.C.. (2024). Placenta Previa Lecture Video. Moodle. Dr. Salvador, F.C. (2024). Vasa Previa. Lecture Video. Moodle. Vessels span before the Vessels are part of the bilobate or succenturiate X. REVIEW QUESTIONS velamentous insertion placenta In a bilobate placenta, the No. QUESTIONS sizes of the lobes are similar. 1 A 24-year-old G3P2 at 31 weeks AOG presented with A velamentous type has one In a succenturiate placenta, vaginal bleeding not associated with uterine contractions. placental plate but the they are dissimilar. What is the MOST likely diagnosis? attachment of the cord is The vessels may run from one A. Placenta previa abnormal lobe then pass along the B. Abruptio placenta The vessels are separate membranes which overly the C. Uterine rupture before they reach the placenta internal os to pursue the other D. Placenta accreta lobe. 2 A G2P1 at 29 weeks AOG, diagnosed with placenta previa, presented with minimal vaginal bleeding. What is the appropriate management? A. Tocolytics for 1 week at home B. Emergency abdominal delivery C. Blood transfusion D. Close observation in high-risk pregnancy unit 3 A 32 year old G2P1 (1001) at 38 weeks AOG is in labor with uterine contractions every 1-2 minutes, 60 seconds C. RISK FACTORS uration, moderate to strong intensity. IE: cervix 2 cm, 70 % effaced, intact membranes, cephalic, station -1 with Placenta In the second trimester of placenta previa, in minimal bleeding. Cardiotocogram showed severe fetal Previa in which the location of the placental plate is at bradycardia. What is the MOST likely diagnosis? 1 second the LUS, a risk for vasa previa is possible. A. Abruptio placenta trimester B. Uterine rupture In Vitro When a pregnancy implants in the LUS, the C. Vasa previa 2 D. Placenta previa Fertilization likelihood of vasa previa increases. 3 Velamentous cord insertion 4 Which structure, if defective or present, contributes to the development of placenta previa? 4 Bilobed/Succenturiate placenta A. Decidual basalis B. Nitabuch’s layer In cases where they may present with two Multiple C. Invading trophoblasts 5 placentas and if they were implanted in the Gestations D. Decidual Necrosis LUS, a chance of vasa previa is more likely. 5 A patient in preterm gestation develops vaginal bleeding with no contractions. What is the most likely diagnostic D. DIAGNOSIS tool to be requested? Antenatally, it can be seen during an initial transabdominal scan. A. Urinalysis with culture This can later be confirmed by the presence of vessels at the B. Transvaginal scan internal os using color doppler during a transvaginal scan. C. CBC with differential count If a speculum examination is done and the cervix is open, D. Non-stress test visualization of the vessels may be possible. 6 Which of the following conditions is associated with 1 Initial transabdominal scan abruptio placenta? A. Hypertension 2 Color doppler during a transvaginal scan B. Previous curettage 3 Speculum examination C. Preterm labor D. Oligohydramnios 7 What is the appropriate management for a patient at 36 weeks AOG, diagnosed with placenta previa, who presented with mild contractions and minimal vaginal bleeding? A. Emergency cesarean section B. Emergency ultrasound C. Elective cesarean section at 38 weeks D. Tocolytics for 1 week 8 What is the cause of bleeding in abruptio placenta? A. Non-contraction of lower uterine segment B. Sustained contraction of the myometrium C. Rupture of the spiral arteries at decidua basalis Figure 34. Vasa Previa ultrasound with color doppler D. Coagulopathy disorder Source: Online Video Lecture - Salvador Vasa Previa 9 The placenta is located in the area of the uterus with more blood and oxygenation. This statement is true in the E. MANAGEMENT following conditions: A. Abruptio placenta To control preterm labor if diagnosed 1 Tocolytics B. Placenta Previa early C. Vasa previa May give before the period of viability D. Normal placenta 2 Corticosteroids and may terminate if labor ensues. 3 Cesarean delivery ALWAYS the manner of delivery Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 11 of 14  10 What is the cause of bleeding in placenta previa? 2 CORRECT ANSWER: D. Close observation in high-risk A. Adherent cotyledons of the placental plate pregnancy unit B. More sinuses in the placental site C. Due to the overlying smooth muscles that poorly contract Letter A is Wrong. it is only indicated if the patient is showing D. Px has some degree of coagulation defect in placenta signs of preterm labor. previa Letter B is Wrong. The fetus is still preterm and there is no 11 Which of the following is the MOST cost-effective modality persistent active bleeding. to diagnose placenta previa? A. Transabdominal ultrasound Letter C is Wrong. Blood transfusion is not warranted because B. Magnetic resonance imaging the patient presented with minimal bleeding, and does not show C. Transvaginal ultrasound any signs of hypovolemic shock. D. Computed Tomographic scan 12 A term patient in labor was delivered by cesarean section. Letter D is Correct. If the fetus is preterm and there is no Operative findings showed hemorrhages seen along the persistent active bleeding, close observation in a high risk serosal areas. What is the most likely diagnosis? pregnancy unit is done. Early admission is a must in order to A. Abruptio Placenta closely monitor the patients diagnosed with placenta previa due B. Placenta Previa to high risk hemorrhage. C. Vasa Previa Ratio Batch 2024 D. Uterine Rupture 3 CORRECT ANSWER: A. Abruptio placenta 13 A term patient complained of labor pains. IE findings revealed cervix 6 cm dilated cephalic, intact BOW, station Letter A is correct because in this case it is the extreme/severe 0. After 1 an hour the patient noticed, watery vaginal fetal bradycardia that points to a possible abruptio placenta discharge. FHT then was 130 bpm. After 3 hours, she delivered a dead pale baby with bloody amniotic fluid. What Letter B is incorrect because in uterine rupture there is gradual is the most likely diagnosis? depression of fetal heart tone until not appreciated A. Vasa Previa B. Uterine Rupture Letter C is incorrect because this only presents when there is C. Abruptio Placenta attempt of deliver/amniotomy D. Placenta Previa Letter D is incorrect because placenta previa because there were no findings of development at the lower uterine segment, XI. RATIONALIZATION there was no bleeding during rest. Ratio Batch 2024 No. RATIONALIZATION 4 CORRECT ANSWER: A. Decidual basalis 1 CORRECT ANSWER: A. Placenta previa The decidua basalis is the portion of the decidua that is related Letter A is correct because “Painless bleeding is the most to the chorion and participates with it in the formation of the characteristic event with placenta previa. Bleeding usually does placenta, becoming the maternal component of the fully formed not appear until near the end of the second trimester, but it can placenta. Thus, a defective decidua basalis will lead to begin even before mid-pregnancy. Bleeding from a previa abnormal placentation. usually begins without warning and without pain or contractions in a woman who had an uneventful prenatal course. B is wrong because Nitabuch's layer is a layer of fibrinoid material that forms between the decidua and the chorionic plate Letter B is incorrect because the signs and symptoms of of the placenta during the third trimester of pregnancy. It is not Abruption placenta include Sudden onset of abdominal pain, related to the development of placenta previa. This, however, is Uterine tenderness, Non-reassuring fetus, Hypertonic uterine involved in the pathology of accrete syndromes. contractions, and Vaginal bleeding. C is wrong because invading trophoblasts are not the pathology Letter C is incorrect Uterine rupture occurs when there is a involved in placenta previa. Invading trophoblasts are actually break involving the entire thickness of the uterine wall involved in normal implantation. (endometrium, myometrium and serosa) or only 2 of the inner layers (endo, myo). It is brought about by the thinness of the D is wrong because decidual necrosis involves the death of uterine wall due to prolonged labor, uterotonics, or the presence decidual cells in the uterine lining, and is not the primary cause of a scar. A uterine rupture can cause abdominal pain, vaginal of placenta previa; abnormal placental implantation is the main bleeding, a change in the contraction pattern, or a factor. nonreassuring fetal heart rate tracing. Ratio Batch 2025 Letter D is incorrect because Placenta accreta has an abnormal 5 CORRECT ANSWER: B. Transvaginal scan placental adherence to the myometrium. Due to partial or total absence of decidua basalis and imperfect development of Transvaginal scan is used to diagnose placenta previa. It is the fibrinoid or nitabuch layer. Totally or partially lacking decidual gold standard and used when the placental edge is still not spongy layer and absent physiologic line of cleavage causing visualized. some or all cotyledons to be densely adherent to the myometrium. A is wrong because urinalysis and culture is used to identify the type and number of bacteria present in your body. RARE Complication of Placenta previa. so assume to most common diagnosis first before going through the rare/ least C is wrong because a complete blood count with differential common diseases count is requested when there is suspicion of infections or the Ratio Batch 2024 like. D is wrong because a non-stress test is used to monitor a fetus heart rate for 20-30 minutes to see if it changes as the fetus moves, and during contractions. Ratio Batch 2025 Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 12 of 14  6 CORRECT ANSWER: A. Hypertension 8 CORRECT ANSWER: C. Rupture of the spiral arteries at decidua basalis Letter A is correct because hypertension has the highest relative risk of abruptio placenta.There is greater risk due to This is correct because in abruptio placenta, rupture of the reduced intravascular fluid volume on top of hypertension. spinal artery causing hemorrhage into the decidua basalis is the first pathophysiological process of placental abruptio. Letter B is incorrect because there is no association of abruptio placenta but is associated with placenta previa PROCESS OF PLACENTAL ABRUPTIO: 1. Rupture of the spinal artery causing hemorrhage into Letter C is incorrect because preterm labor is not associated the decidua basalis. with abruptio placenta however it is associated with vasa previa 2. Formation of the retroplacental cut (hematoma) following the hemorrhage Letter D is incorrect because Oligohydramnios is not associated 3. May separate the decidua basalis from the myometrium with abruptio placenta. However, HYDRAMNIOS is associated that may happen at the periphery or at the central portion with abruptio placenta of the placenta. 4. Lastly, the retroplacental hematoma then compresses the placental plate. Letter A Is incorrect because Non-contraction of lower uterine segment is usually seen in PLACENTA PREVIA(painless vaginal bleeding begins without any warning, or without any contractions). Letter B is incorrect because Sustained contraction of the myometrium compresses the blood vessels which is usually to achieve normal hemostasis. This is followed by the formation of clot, and then arrest/stop bleeding. Letter D is incorrect because Coagulopathy disorder is severe finding/complication in abruptio placenta not the cause of bleeding itself. This has something to do with coagulation abnormalities from the reduction or absence of blood-clotting proteins, known as clotting or coagulation factors causing prolonged bleeding. Ratio Batch 2024 Ratio Batch 2024 7 CORRECT ANSWER: A. Emergency cesarean section 9 CORRECT ANSWER: D. Normal placenta Emergency cesarean section is correct because the mode of Early in pregnancy, implantation of the zygote occurs in the first delivery for patients with placenta previa is always C-section. location with good blood supply and oxygenation in the decidua basalis. Hence, placenta growth is normally towards the fundus Letter B or Emergency ultrasound is incorrect because where there is a good source of blood supply called sonography is only used for diagnosing placenta previa and Trophotropism. need not be repeated. A is wrong because abruptio placenta is the premature Letter C or Elective cesarean section at 38 weeks is incorrect separation of the placenta from its normal implantation before because elective CS delivery is only recommended for women the delivery of the fetus. who are near term and not bleeding. B is wrong because unfavorable conditions allow the zygote Letter D or Tocolytics for 1 week is incorrect because according with the developing trophoblast implant elsewhere as the to Boss And colleagues (2011), tocolytics should only be limited placenta is implanted in the lower uterine segment, over or very to 48 hours of administration. The physiological cardiovascular near the internal cervical os, thus, the development of placenta responses to tocolytic agents that include hypotension and previa. Placenta previa is the premature separation of an tachycardia can mask maternal compromise. abnormally planted placenta resulting in the placenta or a portion of it to become the presenting part. Ratio Batch 2025 C is wrong because vasa previa is a condition in which vessels travel within the membrane and overlie the cervical os as it can then be torn with cervical dilation or membrane rupture, and laceration can lead to rapid fetal exsanguination (Cunningham et al., 2022). It has two types: type 1 is when the vessels are part of the velamentous insertion, while type 2 is when the vessels span before the bilobate or succenturiate placenta. Ratio Batch 2025 10 CORRECT ANSWER: C. Due to the overlying smooth muscles that poorly contract Sentinel bleed is a clinical feature of placenta previa; in here, the internal os dilates and some portion of the placenta separates. Since the lower uterine is a non-contracting segment, bleeding is poorly controlled which exacerbates it. Ratio Batch 2025 Group 8A, 9A, 10A | Bleeding in the Second Half of Pregnancy (Placenta Previa, Abruptio Placenta, Vasa Previa, Uterine Rupture) 13 of 14  11 CORRECT ANSWER: C. Transvaginal Ultrasound Transvaginal ultrasound is correct because it is the gold standard, most accurate sonographic method and is safe even with vaginal bleeding. A is wrong because transabdominal ultrasound is used for quick and accurate placental localization. In a comprehensive study, the internal os was visualized in all cases with transvaginal sonography but only 30 percent with transabdominal sonography (Farine, 1988). B is wrong because magnetic resonance imaging is unlikely to replace sonography for routine evaluation given the availability and cost d