عنوان مقاله [English]
Introduction: Preterm labor (PTL) is a leading cause of infants' mortality and recent findings suggest that assisted reproductive technology (ART) may lead to preterm birth. This study was performed with aim to investigate the relationship between ART and PTL among singleton live-birth in Tehran province.
Methods:This retrospective cohort study was conducted on 4704 pregnant women with singleton live-birth referred to Tehran province from 6-21 July 2015. The association between ART and PTL was evaluated using crude odds ratio and adjusted odds ratio. Also, the association between the cause of infertility and PTL was evaluated among ART births. Data analysis was performed by SPSS software (version 16) and regression logistic method. PResults: Among 4704 singleton women, there were 337 (7.2%) ART pregnancy and 4367 (92.8%) spontaneous pregnancy. The PTL rate was significantly higher in ART pregnancy than spontaneous pregnancy (10.1% vs. 4.9%, P<0.001). Moreover, PTL/Early term rate was significantly higher in ART pregnancy than spontaneous pregnancy (54.0% vs. 43.1%, P<0.001). According to multivariate analysis (adjusted model), PTL and PTL/Early term were 1.99 times (95% CI:1.35-2.92) and 1.39 times (95% CI: 1.11-1.74), respectively more likely to occur among ART singletons compared with spontaneous pregnancy. In ART pregnancies, no association was found between cause of infertility with PTL (P=0.628) and PTL/Early term (P=0.418).
Conclusion:Among singleton live-birth, PTL and PTL/early term rates were two-fold and 1.4-fold higher in ART mothers than spontaneous pregnancy after controlling for confounding factors.