Advanced maternal age and perinatal outcome in twin pregnancies: a meta-analysis.

OBJECTIVE: The current meta-analysis evaluates the perinatal outcomes of twin pregnancies in pregnant women 35 years or older (advanced maternal age) compared with less than 35 years at the time of delivery.

STUDY DESIGN: A search was conducted up to March 2018. Electronic databases that were used in our research included; Embase (NO Medline), Ovid Medline, Cochrane Central Register of Controlled Trials, and Web of Science. Inclusion criteria were twin pregnancies; a comparison between pregnant women aged ≥35 years versus <35 years at the time of delivery and reported perinatal outcomes. Review articles, case reports, and case series were excluded. Data analysis was performed using the Cochrane's Review Manager 5.3 software. Pooled odds ratio for dichotomous outcomes or mean difference for continuous outcomes were calculated using a random effects model. I2 test was performed to assess heterogeneity. The quality of each accepted article was assessed using the Newcastle-Ottawa Scale.

RESULTS: Our search yielded 1622 publications, of which 25 were assessed for eligibility. A total of 13 studies met our final inclusion criteria. In twin pregnancies, advanced maternal age was associated with a lower incidence of preterm birth prior to 37 weeks' gestation (OR 0.89 [95% CI 0.83-0.95]) compared with women under 35 years at the time of delivery. Gestational diabetes (OR 1.57 [95% CI 1.24-1.98]) and cesarean deliveries (OR 1.69 [95% CI 1.52-1.87]) were significantly higher among women in the advanced maternal age group. All other measured outcomes, such as preterm delivery before 32 weeks' gestation, hypertension disorders, small for gestational age, birth weight under 2500 or 1500 g, need for neonatal intensive care admission and perinatal death were comparable between the groups.

CONCLUSIONS: This meta-analysis implies that advanced maternal age mothers in the setting of twin pregnancy is associated with comparable outcomes to nonadvanced maternal age mothers. The only outstanding differences were higher rates of GDM and cesarean deliveries in the advanced maternal age (AMA) group.