Advanced maternal age and adverse perinatal outcome: a review of the evidence.

OBJECTIVE: To examine the evidence in relation to advanced maternal age (35-39 years), physiological risk and adverse perinatal outcome (stillbirth, low birth weight, preterm birth) in high-income countries.
BACKGROUND: This review was conducted against a background of increasing maternal age (>35 years) and concerns for fetal and maternal welfare among this group. Consequent to these concerns, increasing trends of birth intervention such as caesarean section and instrumental birth are seen. Although evidence justifies a high rate of intervention among women aged more than 40 years, the evidence for such intervention in women aged 35-39 years is sketchy and often contradictory.
METHODS: A systematic review was conducted of studies in English, that were published between 2000 and 2010. Studies were included if they had extractable data on maternal age (35-39 years) and perinatal outcomes. Of 102 retrieved publications, nine met these criteria.
FINDINGS: Evidence from this review suggests that rates of adverse perinatal outcome, such as stillbirth, are linked to maternal age 35-39 years. However, rates of increase are modest until 40 years of age or more. The impact of changing maternal socio demographics appears to be of importance but is not yet well understood. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Although risk and rates of adverse perinatal outcome are increased among women aged 35-39 years, midwives and women should also be aware that perinatal outcomes are generally favourable for this group. There is also some suggestion in the literature that social advantage may ameliorate some of the effect of advanced maternal age on perinatal outcome. Further research is required to evaluate the soundness and strength of this association.