Maternal age and preterm births in singleton and twin pregnancies conceived by in vitro fertilisation in the United States.

摘要: Background Among natural conceptions, advanced maternal age (≥35 years) is associated with an increased risk of preterm birth. However, few studies have specifically examined this association in births resulting from vitro fertilisation (IVF). Methods A retrospective cohort study was conducted 97 288 singleton and 40 961 twin pregnancies fresh non-donor IVF cycles using 2006–10 data the Society for Assisted Reproductive Technology Clinic Online Reporting System. Results Rates very early (<28), (<32), birth (<37 completed weeks) decreased increasing both (PTrend <0.01). With women aged 30–34 years as reference, those <30 were at all types births. The adjusted odd ratio (95% confidence interval [CI]) birth, 25–29 1.3 [95% CI 1.1, 1.5], 1.2 1.4], 1.1 1.02, 1.2] singletons. This among younger even more significant ≥35 not any type births. Conclusions In contrast to conception, conceived by IVF. Women who seek treatments before 30 old are higher stages