Does young maternal age increase the risk of adverse obstetric, fetal and neonatal outcomes: a cohort study.

OBJECTIVE

To determine whether young maternal age is associated with increased risks of adverse obstetric, fetal and perinatal outcomes.

STUDY DESIGN

Register-based study using the data from a computerized database of a University Hospital for the years 1994-2001. The study population included 8514 primiparous women aged less than 31 who delivered a singleton infant. Using maternal age as a continuous variable, crude and adjusted relative risks (RRs) were estimated for each maternal and perinatal outcome.

RESULTS

Crude and adjusted RRs of anaemia during pregnancy and fetal death consistently increased with younger maternal age. After adjustment for confounding factors, RRs (95% confidence interval) of fetal death and anaemia were respectively 1.37 (1.09-1.70) and 1.27 (1.15-1.40) for a 16-year-old compared to a 20-year-old mother. Younger mothers had significantly decreased risks of obstetric complications (preeclampsia, caesarean section, operative vaginal delivery and post-partum haemorrhage). Higher prevalence of prematurity and low birth weight in infants born to teenagers were not attributable to young maternal age after adjustment for confounding factors.

CONCLUSION

In our population, younger maternal age was significantly and consistently associated to greater risks of fetal death and anaemia and to lower risks of adverse obstetric outcomes.