Obstetrics Marrow Pg 415-424 (Obstetrics Complications)

Tocolytics

• Tocolytics are used to suppress preterm labor.
• Used in combination with cervical cerclage as tocolytics can help to buy some time for cervical incompetence.
• USG based (Length # Cordocentesis

Cordocentesis

• Fetal blood is taken for analysis
• Indicated for fetal anemia.
• Hb of fetus < 2 SD or Hematocrit < 30% is considered mild anemia
• Hb of fetus ≥ 2 SD or Hematocrit ≥ 30% is considered severe anemia
• If severe anemia is detected at ≥ 35 weeks, delivery is recommended.
• If severe anemia is detected at < 35 weeks, intrauterine blood transfusion is recommended.

Rh Negative Pregnancy

• Delayed cord clamping is recommended in Rh-negative pregnancies if the mother is not sensitized and the ICT status is positive.
• Early cord clamping is recommended in other scenarios.

Fetomaternal Hemorrhage (FMH)

• A normal FMH is < 4 ml.
• Anti-D injection 300 µg/1500 IU is sufficient to neutralize up to 30 ml FMH/15 ml fetal RBC.
• For every 1 ml of extra fetal blood (over 30ml): 10 µg of additional Anti-D is given.
• ↑ FMH (Increased Fetomaternal Hemorrhage) can occur due to:
  • Abdominal trauma
  • Instrumental delivery
  • Twin pregnancy
  • Intra-uterine death
  • Manual removal of placenta.

Anti-D

• Rosette Test is used to screen for FMH
  • (+) ↑ FMH = Positive result
  • (-) ↓ FMH = Negative result
• Kleihauer Betke Test is a quantitative test used to estimate the exact volume of fetal maternal hemorrhage (FMH)
• Dose is within 2 hours of the test
• Singer Alkali Denaturation Test is a qualitative test used to differentiate between vasa previa and placenta previa and to detect FMH

First Trimester Anti-D

• Indicated for abortion, ectopic pregnancy, molar pregnancy, and chorionic villi sampling.
• ACOG recommends 50 µg IM
• RCOG recommends 300 µg IM

Second/Third Trimester Anti-D

• Indicated after amniocentesis, external cephalic/internal podalic version, unexplained bleeding, antepartum hemorrhage, fetal death, and abdominal trauma.

• Dose: 300 µg IM

• There is no role of Anti-D in cordocentesis if sensitization has already occurred (ICT+ve).

• Delivery occurring within 28 days of anti-D administration if sensitization has already occurred (ICT+ve).

Miscellaneous Topics

• Minor Antigens have different risks of sensitization:
  • No risk of sensitization: Lewis, I-Antigen, Duffy-B
  • Risk of Sensitization: Kell, Kidd, Duffy-A

Cervical Incompetence

• Cervical incompetence is a condition in which the cervix thins and dilates prematurely during pregnancy, which can lead to miscarriage or premature birth.

• The definition of a shortened cervix varies but is generally less than 2.5 cm in length.

• The most common cause of cervical incompetence is unknown.

Cervical Circlage

• A surgical procedure done to strengthen the cervix that is performed during pregnancy
• Procedure involves placing a suture around the cervix to keep it closed.

Indications

• History of ≥2 painless abortions (irrespective of USG findings)
• History of incomplete abortion + Cervical length

Different Types of Vaginal Circlage

• McDonald Circlage

  • Purse string in portio vaginalis
  • Dissection of bladder is not done
  • Suture material: Non-absorbable (Propylene)
  • Lower success rate

• Shirodkar Circlage

  • Continuous
  • Bladder is dissected
  • Suture closes to internal Os
  • Higher success rate
  • Suture material: Mersilene tape

• Wurms Circlage (Emergency Circlage)

• Used when cervix is already dilated

• Places 2 sutures in the anteroposterior direction and 1 in the transverse direction

• Performed between 14-24 weeks (up to 28 weeks)

• Suture removal occurs at 37 weeks.

• Abdominal Circlage

  • Indicated if vaginal circlage fails.
  • Laparoscopic procedure.
  • Outdated procedure, LASH & LASH surgery: removes part of cervix and then applies suture
  • Done in non-pregnant females.

Hydrops Fetalis

• A condition where there is excessive fluid accumulation in the fetus.
• Can be immune or non-immune
• Immune hydrops fetalis is the most common type of hydrops fetalis.
• Cause of immune hydrops fetalis:
  • Blood incompatibility
  • Fetal Hb < 4g% +
  • Hematocrit < 15%
• Non-immune hydrops fetalis can be caused by:
  • Cardiovascular abnormalities
  • Chromosomal abnormalities
  • Parvovirus B19 infection
  • Other TORCH infections
  • Anemia

Hydrops Fetalis Diagnosis

• Ultrasound (USG) findings:
• Pericardial effusion
• Ascites
• Pleural effusion
• Subcutaneous edema
• "Buddha sign" (scalp subcutaneous edema)

Recurrent Miscarriage

• ≥ 2 consecutive pregnancy losses at ≤20wk of gestation
• Two confirmed pregnancy losses by American Society of Reproductive medicine (ASRM).
• Confirmation by Histopathological examination (HPE) & USG
• Most common causes:
  • Maternal:
    • Endocrine:
      • Hypothyroidism
      • Uncontrolled diabetes
    • Uterine:
      • Congenital: Septate uterus > Bicornuate uterus (T2 > Ta)
      • Acquired: - Cervical incompetence (only T abortions) - Submucous fibroid - Ashermann syndrome
  • Chromosomal Abnormalities
    • Can lead to 2 to 5% of recurrent abortions.
    • Most common: Balanced translocation of chromosomes

Recurrent Miscarriage Investigation

• Start after 2 abortions:

  • TSH (if endocrine cause suspected)
  • TVS (if uterine cause suspected)
  • Antiphospholipid antibody (APLA) Ab-testing
  • Parental Karyotyping

• Investigations not done:

  • TORCH (in infections) - Including VDRL test for syphilis.
  • Thrombophilia

This quiz covers essential aspects of tocolytics, their role in preterm labor, and the procedure of cordocentesis for fetal blood analysis. It also addresses the management of Rh negative pregnancies and fetomaternal hemorrhage. Test your knowledge on these critical topics in obstetric care.