Neonatal intensive care utilization and neonatal outcome of infants born to women aged 40 years and over in New Zealand.

BACKGROUND: Increased maternal age is associated with pregnancy complications and there are few data available on neonatal outcome and utilization of neonatal resources. Our first aim was to use national New Zealand data to determine if the outcomes following admission to NICU are different for infants born to women aged 40 years and over, compared with those born to women under 40 years of age. The second aim was to document trends in the requirement of neonatal intensive care in infants born to women aged 40 years and older. METHOD: Eligible infants were identified from registration with the Australian and New Zealand Neonatal Network for 1995-2004 inclusive. The relationship between maternal age and neonatal outcome was tested using univariate and multivariate analysis, and trends in the number of infants in maternal age groups below 35 years, 35-39 years and over 40 years were determined. RESULTS: On multivariate analysis using logistic regression, maternal age over 40 years was not found to be associated with a significant increase in the odds ratio for the composite poor outcome. However, over the 10-year period, there was an increase in the number of admissions and the percentage of admissions of infants born to women over 40 years of age. CONCLUSION: Although the number of infants admitted for neonatal care following birth to women over 40 years of age has increased, these infants do not appear to have an increased risk of severe abnormal outcome.