Advanced Maternal Age, Pregnancy and Birth

Maternal age of 35 years and over has increased in Western countries as well as in Finland during the last decades. The purpose of this retrospective register-based study was to explore the risks and complications related to pregnancy and birth of women aged 35 years or older, when comparing them to younger women aged less than 35 years old. Pregnancy outcomes and complications were observed in four different groups of older women: women diagnosed with preeclampsia, women who were smoking, who were overweight or obese and who were diagnosed with gestational diabetes mellitus (GDM). The aim was at first to compare them to younger women with low-risk pregnancies and further evaluate the risk caused independently by advanced maternal age (AMA) and the existing risk factor (smoking, overweight and obesity and GDM) in the group of AMA women to estimate whether the risk was increased in AMA women. The data consisted information of 690 555 women and their newborns and the data were analysed by statistical methods. The present study was conducted by merging three different Finnish health registries (Medical Birth Register, Hospital Discharge Register and Register of Congenital Malformations) into one data covering the years 1997-2008. The permission to use the data was gained from the National Institute for Health and Welfare (THL), who is controlling the registries. The information of the Register of Congenital Malformations was used only as exlusion criteria, when cases in which the baby had a major congenital anomaly were exluded from the data. The findings showed that AMA women had increased risks related to pregnancy and birth compared to younger women aged less than 35 years old. AMA independently was not as large a risk as the existing risk factor (smoking, overweight and obesity and GDM) in the group of AMA women, when the risks were significantly increased. AMA women with preeclampsia had increased risk especially for preterm deliveries and small-for-gestational-age-infants (SGA). AMA women who were smoking had increased risk especially for low birth weight (LBW), preterm deliveries, foetal death and SGAinfants. AMA women who were overweight or obese had increased risk especially for preterm deliveries, foetal death, large-for-gestational-age—infants (LGA), Caesarean and preeclampsia. AMA women diagnosed with GDM had increased risk especially for preterm deliveries, foetal death, LGA-infants and preeclampsia. The present study demonstrated that these four groups of AMA women are distinct highriks groups, who should be identified early in maternity care clinics as being “at risk” when the potential complications could be detected early and the harm for both the mother and the foetus could be prevented and reduced. National Library of Medicine Classification: WQ240 Medical Subject Headings: Pregnancy outcome; Maternal age; Pregnancy; High-risk, Risk factors, Pregnancy Complications; Maternal Health Services; Registries; Retrospective studies