Comparison of Demographic and Obstetric Characteristics of Canadian Primiparous Women of Advanced Maternal Age and Younger Age

Objective: The rate of pregnancy at advanced maternal age (AMA) has increased during recent decades. The purpose of this study is to compare demographic and obstetric characteristics of Canadian primiparous women of AMA with those aged 20 to 29 years. Methods: We conducted a secondary analysis of data collected through the national Maternity Experiences Survey (MES) of the Canadian Perinatal Surveillance System. The sample included 301 primiparous women aged 35 years or over and 1564 primiparous women aged 20 to 29 years. Estimates of prevalence for each group and their odds ratios were calculated using sample weights of the survey, and variances were calculated using bootstrapping methods adjusting for sampling design and weights. Results: Women of AMA were significantly more likely to be better educated, to have higher income, to be employed, and to continue to work until the end of pregnancy than younger women. They also reported having significantly more information on pregnancy, labour, and birth, and they were more likely to attend prenatal classes. They were more likely to have had a miscarriage or infertility treatment, to request or be offered a Caesarean section, and to have a higher rate of Caesarean section. There were no significant differences in rates of preterm birth, low birth weight, and small-for-gestational age infants. Conclusion: Pregnant women of AMA differ from younger women in demographic characteristics, knowledge level, and some health behaviours and pregnancy outcomes. The growing number of pregnancies at AMA indicates the need for developing appropriate care plans to address the specific needs of this group.