Stillbirth

Question 1

The equation for calculating fetal mortality is…?

Answer 1

=number of stillbirths divided by 1000 live births + stillbirths

Question 2

Which ethnic group has the highest risk of stillbirth?

Answer 2

Non-hispanic black women: 10.43 deaths per 1000 livebirths(LB) and stillbriths(SB). This disparity persists when adjusted for adequate PNC, education level.
Followed by:
- 6.22 deaths per 1000 LB+SB for Am. Indian or Alaska Native
- 5.22 deaths per 1000 LB+SB for Hispanic white
- 4.88 deaths per 1000 LB+SB for non-Hispanic white
- 4.68 deaths per 1000 LB+SB for Asian or Pacific Islanders

Question 3

T or F: Antiphospholipid syndrome and inherited thrombophilias are associated with increased risk of stillbirth.

Answer 3

False:

• APS is an acquired thrombophilia that is associated with stillbirth.
• Inherited thrombophilias NOT associated with stillbirth and it is not recommended to test as part of stillbirth evaluation.

Question 4

What is the most common MODIFIABLE risk factor for stillbirth?

Answer 4

Obesity and increased maternal weight gain.
Risk of stillbirth by BMI:
- BMI 20 (4.0/1000 pregnancies), BMI 25 (4.8/1000 pregnancies), BMI 30 (5.9/1000 pregnancies)
Obesity-related stillbirth increases with GA and is likely multifactorial. Optimal BMI remains unknown.

Question 5

T or F: The amount or “dose” of cigarette smoking affects the level of risk of stillbirth.

Answer 5

Tobacco use leads to 47% increased odds of stillbirth
Dose-response effect has been seen.
Secondhand smoke increases risk, comparable to some active smokers. Quitting between pregnancies is protective.

Question 6

Stillbirth evaluation includes…

Answer 6

Maternal evaluation (depending on clinical clues): KB, syphilis, urine drug screen, A1c, APS evaluation.
Fetal evaluation: gross inspection of fetus, placenta, umbilical cord, and membranes. Obtaining parental consent for cytogenetic analysis (fetal karyotype or microarray) and fetal autopsy. Obtain specimens for cytogenetic analysis (amniotic fluid, placental block, umbilical cord specimen, or internal fetal tissue). Pending parental consent, send fetus and placenta to pathology.

Question 7

Antiphospholipid antibody testing is indicated in which cases of stillbirth?

Answer 7

• Fetal growth restriction or hypertensive disorder
• Intrapartum stillbirth
• No other clinical clues as to cause of stillbirth

Testing includes: 
Lupus anticoagulant
Anticardiolipin IgG and IgM
Beta-2 glycoprotein IgG and IgM
* Must be repeated after 12 weeks to confirm diagnosis

Question 8

T or F: Cord entanglement occurs in ~25% of normal pregnancies and deliveries.

Answer 8

T: Stillbirth Collaborative Research Network determined that nuchal cord alone was not considered cause of stillbirth. Cord events that can lead to stillbirth include:
Vasa previa, cord entrapment, evidence of occlusion with fetal hypoxia, prolapse, stricture with thrombi

Question 9

Before 28 weeks, what methods of delivery can be offered?

Answer 9

Depending on patient’s goals (intact fetus vs predictable completion time), D&E or IOL can be offered.
- D&E may limit efficacy of autopsy for macroscopic anomalies and precludes seeing/holding fetus
- IOL in 2nd trimester:
Higher risk of D&C for retained placenta
Increased risk of infection, IV antibiotics
Less effective, higher complication rate (between 13 and 24 weeks)

Question 10

Before 28 weeks, what is the most effective way to induce labor in cases of stillbirth

Answer 10

Misoprostol 400-600 mcg PV q3-6 hours
Mifepristone 200 or 600 mg orally (24-48 hrs before induction with misoprostol) can be used as adjunct to misoprostol, reduces time to delivery. However, does not appear to increase overall efficacy of induction.
*After 28 weeks, IOL managed according to usual obstetric protocols

Question 11

How should subsequent pregnancies be managed (antepartum surveillance, delivery timing) in patients with a history of stillbirth?

Answer 11

• Minimize modifiable risk factors
• Evaluation and workup of previous stillbirth
• Acquired thrombophilia workup
• Genetic counseling
• Offer genetic screening, detailed anatomy scan at 18-22 weeks, AFP, etc
• Surveillance for fetal growth restriction via US starting at 28 weeks
• Antenatal testing 1-2x weekly starting at 32 weeks or 1-2 weeks before GA of stillbirth (if DM, HTN then perform antenatal testing as indicated for comorbid condition)
• Delivery at 39 weeks versus early term delivery (37w0d-38w6d) considered in cases of severe patient anxiety when educated regarding associated neonatal risks.

Question 12

When is it okay to use vaginal misoprostol for IOL for stillbirth in patients with a history of prior uterine scar?

Answer 12

• <24 weeks gestation with prior uterine scar, PV misoprostol okay
• 24-28 weeks gestation with prior uterine scar, needs further study to evaluate safety, route, and dosing
  >28 weeks with prior uterine scar, undergo IOL per standard OB protocols for TOLAC rather than misoprostol
• history of classical or multiple LTCS, plan should be individualized and cesarean delivery considered.