Pregnancy outcomes in women of very advanced maternal age.

Objective: To assess outcomes for pregnancies progressing beyond 20 weeks' gestation in women of very advanced maternal age.

Design: Retrospective cohort study.

Setting: Two tertiary level obstetric hospitals.

Population: Women aged 45 years or more at the time of delivery over a 10-year period from 1 January 1992 to 31 December 2001.

Methods: Information regarding maternal, pregnancy and neonatal outcomes was obtained from the medical records. For comparison, routinely collected data from the obstetric database was obtained for women aged 20-29 years.

Results: Seventy-seven pregnancies in 76 women aged 45 years and over were registered in the 10-year period. There were 74 liveborn singletons, two sets of liveborn twins and one set of twins stillborn at 20 weeks' gestation. Sixteen women were primiparous. Eighty-four percent of pregnancies were conceived naturally and 53% underwent prenatal chromosomal determination; 53% of women had no pre-existing medical problems, 13% had hypertensive disorders of pregnancy and 8% of women developed gestational diabetes. There were 10 preterm and six post dates deliveries. The Caesarean section rate was 49%, compared to 23% in the 20-29 years age group (P < 0.001). Ten percent of neonates were small for gestational age, and 8% were large for gestational age. Seventeen percent required admission to the special care nursery and 6% had congenital abnormalities.

Conclusions: Maternal and neonatal outcomes in this series were generally good. There was a significantly increased rate of Caesarean section. Overall, this study is reassuring for women aged 45 and over who have good general health and a chromosomally normal fetus.