Maternal Age at Childbirth and Perinatal and Under five Mortality in a Prospective Birth Cohort from Delhi.

OBJECTIVE: To evaluate the relationship between maternal age at child birth, and perinatal and under-five mortality.

DESIGN: Prospective birth cohort.

SETTING: Urban community.

PARTICIPANTS: 9169 pregnancies in the New Delhi Birth Cohort resulted in 8181 live births. These children were followed for survival status and anthropometric measurements at birth (+3 days), 3,6,9 and 12 months (7 days), and every 6 months thereafter until 21 years age. Information on maternal age at child birth and socio-demographic profile was also obtained.

OUTCOME MEASURES: Offspring mortality from 28 weeks gestation till 5 years age.

RESULTS: Offspring mortality (stillbirths - 5 years; n=328) had a U-shaped association with maternal age (P<0.001). Compared to the reference group (20-24 years), younger (≤19 years) and older (≥35 years) maternal ages were associated with a higher risk of offspring mortality (HR: 1.68; 95% CI 1.16, 2.43 and HR 1.48; 95% CI 1.01, 2.16, respectively). In young mothers, the increased risk persisted after adjustment for socio-economic confounders (maternal education, household income and wealth; HR 1.51; 95% CI 1.03, 2.20) and further for additional behavioral (place of delivery) and biological mediators (gestation and birthweight) (HR 2.14; 95% CI 1.25,3.64). Similar associations were documented for post-perinatal deaths but for perinatal mortality the higher risk was not statistically significant (P >0.05). In older mothers, the increased mortality risk was not statistically significant (P >0.05) after adjustment for socio-economic confounders.

CONCLUSION: Young motherhood is associated with an increased risk of post-perinatal mortality and measures to prevent early childbearing should be strengthened.