IUFD Quick Facts PB102
Stillbirth = delivery of fetus with no signs of life, 20+ weeks if GA known / 350+ grams if GA unknown, excludes terminations for lethal anomalies and IOL for pre-viable PPROM, occurs in 6.2/1000 births (evenly split between 20-27 week and 28+ week groups)
- - Risk Factors: Non-Hispanic black race (11.25 vs 6/1000 even with adequate PNC), nulliparity, AMA (11-14/1000 if 35-39, 11-21 if 40+) and obesity (5.5/1000 for Class I, 8/1000 for Class II, 11/1000 for Class III) are the most prevalent. Also congenital anomalies, abnormal karyotypes, fetal growth restriction, placental abnormalities, thrombophilia, hypertensive disorders, diabetes, SLE, renal disease, thyroid disorders, cholestasis, infections including B19/CMV/syphilis/strep/listeria, multiple gestation, smoking, drug use.
o Risk of stillbirth in pregnancy, after prior pregnancy with IUGR and livebirth before 32 weeks, is 21.8/1000 (twice as high as risk of recurrent stillbirth)
o Complete maternal history
o Physical exam of fetus with descriptions, photos if possible
o Laboratory studies (placenta pathology, fetal autopsy, karyotyping = most important)
· Alternatives to autopsy: X-rays, ultrasounds, MRIs, blood/tissue samples
· Dysmorphic features/skeletal abnormalities are found in 20% of stillbirths, major malformations in 15-20%.
· Abnormal karyotype is present in 8-13% of stillbirths, but rate is likely underestimated, as up to 50% of cell cultures don’t yield results. Monosomy X (23%), T21 (23%), T18 (21%) and T13 (8%) most common.
· Inherited thrombophilia work-up (FVL, prothrombin, ATIII, Protein C &S, MTHFR/homocysteine) only if severe placental pathology, significant fetal growth restriction or personal/ family history of thrombosis. Protein C&S have to wait until post-partum.
· ANA, Toxo, Rubella, CMV, HSV are of unproven benefit
o <28 weeks: Vaginal misoprostol preferred regardless of Bishop score even in patients with h/o cesarean (200-400 mcg q4-12h)
o >28 weeks: Manage as you normally would based on Bishop score. Use intracervical balloon for unfavorable cervix, rather than misoprostol.
Pregnancy After Stillbirth
- Recurrence of stillbirth in low-risk women with negative work-up/unexplained stillbirth is low at 7.9-10.5/1000 and most of these occur preterm
- Preconception: detailed history, completion of any IUFD work-up not previously done, determine of recurrence risk, smoking cessation and weight loss counseling if applicable,
genetic counseling if applicable, DM screening
- 1st trimester: dating/viability US and serum screening + NT
- 2nd trimester: anatomy US at 18-20 weeks and MSAFP
- 3rd trimester: US for IUGR after 28 weeks, kick counts at 28 weeks, antepartum monitoring…
- Evidence is limited re: antenatal monitoring, most initiate at 32-34 weeks or 1-2 weeks earlier than prior stillbirth, risk of recurrent stillbirth must be weighed against risk of iatrogenic PTB after delivery for false+ testing
- Delivery at 39 weeks gestation, earlier only with +FLM by amnio