False-Positive Results in Pregnancy Screening for Aneuploidy

Objectives: The screening of chromosomal aberrations is one of the most common methods during pregnancy although this test is occasionally false-positive. Materials and Methods: In this case-control study, 252 mothers with false-positive (n=126) and -negative (n=126) tests were evaluated respectively. Demographic data during pregnancy and postpartum included maternal and neonatal complications, and finally, perinatal variables were compared between the two groups. Results: The mean age of the case group was significantly higher than that of the control group (P < 0.001). In addition, lower smoking history in the spouse (P = 0.01), higher prevalence of preeclampsia (P = 0.33) and proteinuria (P = 0.03), preterm infant (P = 0.01), and low birth weight (P = 0.04) were observed in this group as well. Eventually, the shorter height P = 0.004) and lower 5-minute Apgar score (P = 0.03) were found in infants. Conclusions: In general, mothers with positive screening results showed a higher risk of preeclampsia and preterm labor in comparison with those with false-negative screening results.