Miscarriage risk from amniocentesis performed for abnormal maternal serum screening

Area of Science:

• Perinatal medicine
• Maternal-fetal medicine
• Reproductive genetics

Background:

• Abnormal maternal serum screening in mid-trimester pregnancies necessitates further evaluation.
• Amniocentesis is a common diagnostic procedure, but concerns about miscarriage risk persist.

Purpose of the Study:

• To evaluate the association between mid-trimester amniocentesis and miscarriage in women with abnormal maternal serum screening results.

Main Methods:

• Analysis of summary data from 32,050 women in California with abnormal serum screening, singleton fetus, and normal ultrasound.
• Comparison of miscarriage rates, timing, and maternal factors between women who underwent amniocentesis and those who did not.

Main Results:

• The miscarriage rate was 0.46% with amniocentesis versus 0.53% without (P = .38).
• No significant differences were observed in maternal age, serum biochemical factors, gestational age at miscarriage, or days until miscarriage between the groups.
• Statistical analysis confirmed no difference in miscarriage timing between the amniocentesis and no-amniocentesis groups (P = .61 for gestational age, P = .40 for days until miscarriage).

Conclusions:

• Mid-trimester amniocentesis does not appear to increase the risk of miscarriage in women with abnormal maternal serum screening.
• The rate and timing of miscarriage are comparable whether or not amniocentesis is performed in this specific patient population.