Pregnancy outcomes of overweight and obese women aged 35 years or older – A registry-based study in Finland

SummaryObjectiveTo compare pregnancy outcomes of overweight and obese pregnant women aged 35 years or older to women aged less than 35 years old.MethodsA registry-based study covering years 2004–2008 including data on women ≥35 years (N = 45,718) compared to those <35 years (N = 203,930) and their pre-pregnancy body mass index (BMI) (<25, 25–29 and ≥30). In multivariable modelling, the main outcome measures were preterm delivery (<28 weeks, 28–31weeks and 32–36 weeks), low Apgar scores at 5 min, small-for-gestational age (SGA), foetal death, asphyxia, Caesarean section, induction, preeclampsia, blood transfusion, admission to a neonatal intensive care unit (NICU), shoulder dystocia, and large for gestational age (LGA).ResultsMaternal overweight and obesity along with advanced maternal age (AMA) significantly increased the risks of preterm delivery, preeclampsia, foetal death, LGA and Caesarean as compared to women of average weight aged <35 years. When comparing overweight and obese women aged ≥35 years to normal weight women of the same age, the rates of preeclampsia, preterm delivery <28 weeks, LGA and low Apgar score were significantly increased. When observing overweight and obese women <35 years as a reference group, the risks of preterm delivery and foetal death were significantly increased.ConclusionsThe risks were increased by maternal age ≥ 35 years and both obesity and overweight. The combined effect of AMA and either overweight or obesity appeared to be a high risk state particularly for stillbirth and preterm delivery.