Nonspontaneous twin gestation increases odds for adverse neonatal outcomes
Twins conceived through assisted reproductive technology or fertility-enhancing drugs were more likely to have adverse neonatal outcomes compared with those who were conceived spontaneously.
“The number of fertility treatments and, consequently, the number of births conceived through fertility treatments have continued to increase in the United States,” Afsoon Ghafari-Saravi, an MD candidate at Oregon Health & Science University, told Healio. “Fertility treatments, including assisted reproductive technology (ART) and non-ART treatments such as fertility-enhancing drugs, make conceiving a child possible for those who face infertility. However, fertility treatments are associated with a higher rate of multifetal gestations.
“Existing research shows that multifetal gestations come with greater adverse outcomes for both mother and neonate,” Ghafari-Saravi said. “However, there is more to understand [about] multifetal gestations conceived with fertility treatments [and if they] pose an even greater risk for adverse neonatal outcomes than multifetal gestations conceived spontaneously without any fertility treatments.”
Ghafari-Saravi and colleagues reviewed linked vital statistics-patient discharge data available in California from 2007 to 2011 and included data from 64,500 twins born between 23 and 42 weeks’ gestation and their mothers for analysis. They compared demographics and neonatal outcomes between pregnant patients who used ART or fertility-enhancing drugs or who conceived spontaneously.
The findings, presented at the Society for Reproductive Investigation Annual Meeting, showed spontaneous gestation was most common in the study population (n = 56,803; 88.07%), followed by 5,808 (9%) ART gestations and 1,889 (2.93%) fertility-enhanced gestations. Patients using nonspontaneous conception methods were significantly more likely to be white, older, highly educated, privately insured and have normal BMI, the researchers wrote.
Compared with spontaneously conceived pregnancies, pregnancies conceived using fertility-enhancing drugs had greater odds of NICU admission (adjusted OR = 1.41; 95% CI, 1.28-1.56) and respiratory distress syndrome (aOR = 1.27; 95% CI, 1.15-1.42).
Odds of NICU admission (aOR = 1.2; 95% CI, 1.13-1.27) and respiratory distress syndrome (aOR = 1.12; 95% CI, 1.05-1.2) were also higher with ART, as were the odds of infant death (aOR = 1.35; 95% CI, 1.03-1.78) and congenital anomalies (aOR = 1.11; 95% CI, 1.02-1.21).
“Our findings raise important questions as to why multifetal pregnancies conceived with fertility treatments increase the likelihood of adverse outcomes,” Ghafari-Saravi said. “Could it be due to pre-existing issues surrounding the mother's sub-fertility, or could it be due to the effect fertility treatments themselves have on placental or fetal development? As the research continues to develop on how to best answer that question, our study highlights the potential need to require closer follow-ups throughout gestation to reduce adverse neonatal outcomes.”