Objectives: To compare the rates of adverse neurodevelopmental outcome or death at 18 to 22 months among extremely low birth weight (ELBW) infants born to mothers >or=4 0 years to the corresponding rates among infants of younger mothers.
Study design: Prospective evaluation of ELBW infants to quantify the relative risks of maternal age and multiple birth for death or adverse neurodevelopmental outcome.
Results: The sample consisted of 14 671 live ELBW births divided into maternal age groups: <20, 20 to 29, 30 to 39, and >or= 40 years. Of infants born to mothers >or= 40 years, 20% were multiples. Mothers >or= 40 years had high rates of obstetric interventions and medical morbidities compared with mothers <40 years. ELBW live births of mothers >or= 40 years were 22% more likely to survive and had a 13% decreased risk of neurodevelopmental impairment or death compared with mothers <20. Multiple birth, however, was associated with a 10% greater risk of neurodevelopmental impairment or death.
Conclusion: Although mothers >or= 40 years had high pregnancy-related morbidities, we found no overall increased risk of the composite outcome of death or NDI. Multiple birth, however, was a predictor of all adverse outcomes examined, regardless of maternal age.