Obstetrics Quiz on Vasa Previa

Placenta Complications in Pregnancy

• The placenta is a vital organ developing during pregnancy, acting as a life support for the fetus.
• Placenta functions include nutrient and oxygen transfer from mother to fetus, waste removal from fetus to mother, hormone production (e.g., HCG, progesterone), and immunological protection against infections.
• Placental complications pose significant risks to both the mother and the fetus.

Placental Abruption

• Placental abruption is the premature separation of the placenta from the uterine wall before delivery.
• It commonly occurs around 25 weeks of pregnancy.
• Types of placental abruption include:
  • Partial: Placenta separates in a small area; mild cases may involve monitoring and activity restrictions.
  • Complete: Placenta separates completely from the uterine wall, usually resulting in significant bleeding requiring immediate delivery.
  • Revealed: Moderate to severe visible vaginal bleeding.
  • Concealed: Little or no visible vaginal bleeding, with blood trapped between the placenta and uterine wall.
• Severity can be classified into grades (1-3) based on the percentage of detached placenta. Higher grades have more severe symptoms.

Risk Factors for Placental Abruption

• Smoking
• Early membrane rupture during pregnancy
• Placental abruption in prior pregnancies or family history of placental abruption
• Uterine infections during pregnancy
• Cocaine use during pregnancy
• Mother has asthma
• Maternal age of 35 or older
• Carrying multiple babies
• Hypertension or related pregnancy problems (e.g., preeclampsia, eclampsia)
• Maternal exposure to air pollution
• A fall or blow to the abdomen during pregnancy
• Water breaks before 37 weeks

Symptoms of Placental Abruption

• Sudden lower abdominal pain
• Problems with the baby's heart rate
• Vaginal bleeding
• Tense, rigid uterus
• Fetal distress (e.g., decreased fetal movement)
• Dangerously low blood pressure

Diagnosis of Placental Abruption

• Physical exam: Checks for uterine tenderness/rigidity.
• Ultrasound: Uses high-frequency sound waves to image the uterus and locate bleeding. Not always conclusive.
• Blood and urine tests: May include CBC, blood/Rh typing, PT/PTT, fibrinogen, and fibrin-split products.
• Fetal monitoring: Monitors fetal heart rate and movement.

Management of Placental Abruption

• Initial Assessment: Vital signs (BP, heart rate, respiratory rate), fetal heart rate monitoring, physical exam for uterine abnormalities, and estimation of blood loss.
• Stabilization: IV fluids and possible blood transfusions, oxygen therapy, and blood tests (hemoglobin, hematocrit, coagulation profile, and organ function).
• Delivery Consideration: If fetal distress or the pregnancy is term - Cesarean section is the preferred method. Stable mother/fetus - Longer hospital observation.
• Postpartum Care: Monitor for hemorrhage, uterine tone, signs of shock, and close maternal monitoring in the immediate postpartum period.

Placenta Previa

• Placenta previa: Placenta attaches inside the uterus near or over the cervical opening.
• Symptoms: Vaginal bleeding in the second half of pregnancy; bright red, usually painless.
• Types of Placenta Previa:
  • Complete: Placenta completely covers the cervical opening.
  • Partial: Placenta covers part of the cervical opening.
  • Marginal: Placenta is near the cervical opening but does not cover it.
  • Low-lying: Placenta is low in the uterus but does not cover the cervical opening.
• Causes/Risk Factors: Twin or multiple pregnancies, prior pregnancies, short time between births, prior cesarean sections, uterine scars from prior abortions or surgeries, advanced maternal age, and tobacco/cocaine use.
• Diagnosis: Ultrasound to check the location of placenta.
• Symptoms: Painless vaginal bleeding, usually bright red, occurring in the second half of pregnancy.
• Management: Close monitoring, possible hospitalisation according to the type and severity. Cesarean section delivery is preferred; vaginal delivery may be possible if the condition is diagnosed early and the placenta is low-lying.

Placenta Accreta, Increta, and Percreta (PAS)

• Placenta accreta: Placenta attaches abnormally firmly to the uterine wall.
• Placenta increta: Placenta penetrates deeply into the uterine muscle.
• Placenta percreta: Placenta penetrates through the uterine wall potentially invading nearby organs.
• These conditions increase in severity as they progress through accreta, increta, and percreta (the most severe).

Risk Factors for PAS

• Previous uterine surgery (e.g., C-sections)
• Placenta previa
• Advanced maternal age
• History of multiple pregnancies

Complications of PAS

• Life-threatening maternal hemorrhage
• Large-volume blood transfusions
• Peripartum hysterectomy
• Preeclampsia
• Preterm labor
• Disseminated intravascular coagulation (DIC)
• Shock

Vasa Previa

• Vasa previa: Fetal blood vessels cross or run near the internal opening of the uterus
• Types of vasa previa:
  • Velamentous insertion: Blood vessels travel from the membranes of the placenta
  • Succenturiate placenta: Blood vessels originate from a separate lobe of the placenta.
• Complications: Fetal blood vessel rupture, leading to severe blood loss or fetal death. Bleeding during labor
• When diagnosed early, cesarean section is crucial to prevent life-threatening hemorrhage.
• Routine prenatal monitoring and testing (e.g. ultrasound, Doppler flow studies) aid in diagnosis.

Placental Insufficiency

• Placental insufficiency: Placenta doesn't adequately provide nutrients and oxygen to the fetus.
• Causes: Placenta damage/developmental defects.
• Symptoms: Fetal growth restriction or SGA, Decreased fetal movement, non-reassuring fetal heart rate patterns (e.g., variable decelerations). Maternal symptoms could include: hypertension, swelling, protein in urine.
• Diagnosis: Ultrasound, Doppler flow studies, non-stress tests (NST), biophysical profile (BPP).

Retained Placenta

• Definition: Part of the placenta remains in the uterus after delivery.
• Causes: Poor uterine contractions, uterine atony, placental abnormalities (e.g., accreta, increta, percreta) and prior uterine surgeries, uterine anomalies.
• Common causes, not related to the abnormalities above, include large-size babies, multiple births, extended labor, oxytocin use and magnesium sulfate infusions.
• Symptoms: Postpartum hemorrhage, difficulty in placental ejection, infection signs (e.g., fever, bad-smelling discharge), abdominal pain.
• Management: Manual removal, uterine massage, utero-tonics (e.g., oxytocin), surgical removal (e.g., curettage or hysterectomy if required), antibiotics and blood transfusions (if needed)