Is primiparity a risk factor for advanced maternal age pregnancies?

Objective: Currently, more women are delaying childbearing until their 40s. This study compared the pregnancy and maternal features, pregnancy and foetal outcomes between multiparous and primiparous patients. We compared the same factors between assisted reproductive technology (ART) and non-ART primiparous patients because of the high proportion of ART used in the primiparous patients. Methods: The study retrospectively examined 1680 patients, 35 years of age and older, between March 2008 and February 2015. Results: Comparing the features of these two groups, there was an increased incidence of employment and the use of ART in primiparous patients, while birth weight tended to be higher in the multiparous group. There were no significant differences in pregnancy complications other than hypertension disorders, such as pre-eclampsia and HELLP syndrome, which were significantly more frequent in primiparous patients. The rates of foetal growth retardation and perinatal death were significantly higher in primiparous women. Comparison of the data between ART and non-ART primiparous patients indicated that the ART group had a higher initial body mass index and a lower smoking rate. No significant differences in pregnancy complications or foetal outcome were observed between these two groups. Conclusion: Primiparity is associated with increased pregnancy and foetal complications in advanced age pregnancies. However, the use of ART in this age group does not seem to be an additional risk factor.