Women who conceive through assisted reproductive technology are at a 42% higher risk for placental abruption and a 46% higher risk for preterm delivery compared to those with spontaneous pregnancies, according to a recent study.
The cross-sectional study, published in JAMA Network Open, assessed the association between assisted reproductive technology (ART) and the risks of placental abruption and preterm delivery using data from 78,901,058 U.S. women who delivered between 2000 and 2019.
The findings indicated that pregnancies conceived via ART have an increased risk of both placental abruption and preterm delivery compared to spontaneous conceptions. The adjusted odds ratio (aOR) for placental abruption in ART pregnancies was 1.42 (95% confidence interval [CI] = 1.34-1.51) and the aOR for preterm delivery was 1.46 (95% CI = 1.42-1.51).
The average age of the mothers in the study was 27.9 years (standard deviation = 6.0 years). The breakdown of hospital deliveries showed that 44.2% were among White women, 18.9% among Hispanic women, 11.7% among Black women, and 25.2% among women of other races and ethnicities.
Singleton pregnancies accounted for 98.2% of all hospital deliveries in the study. For those conceived through ART, the aOR for placental abruption was 1.46 (95% CI = 1.37-1.56). Additionally, the aOR for preterm delivery in these singleton ART pregnancies was 1.62 (95% CI = 1.57-1.67).
When both ART conception and placental abruption occurred together, the relative excess risk due to interaction (RERI) for preterm delivery was calculated at 2.0 (95% CI = 0.5-3.5). The preterm delivery rate was notably higher, at 555 per 1,000 births in cases with both factors, compared to 156 per 1,000 for ART conception alone and 421 per 1,000 for placental abruption alone.
Additionally, the study found that the combination of ART conception and placental abruption further increases the risk of preterm delivery beyond the risks conferred by either factor alone. The RERI analysis indicated an increased risk, particularly in White women, while the association was less pronounced in Black and Hispanic women.
Full disclosures can be found in the published study.