Background
Some cardiovascular disease risk factors are associated with both risk of preeclampsia and having been born to a younger or older mother. We examined whether mother's age at delivery predicts a primiparous daughter's risk of preeclampsia.
Methods
The analysis included 39 803 Sister Study participants (designated as “daughters”) born between 1930 and 1974. Using log‐binomial regression, we estimated relative risks (RR) of preeclampsia in the first pregnancy ending in birth (“primiparous preeclampsia”) associated with mother's age at the daughter’s birth. Models included: number of older full and maternal half‐siblings, income level growing up, daughter's age at delivery, race/ethnicity, and 5‐year birth cohort. We examined self‐reported relative weight at age 10 (heavier than peers versus not) as a potential effect measure modifier.
Results
Overall, 6.2% of daughters reported preeclampsia. Compared with those who had been born to 20‐24‐year old mothers, daughters of teenage mothers had a relative risk of 1.20 (95% confidence interval (CI) 1.01, 1.43) and daughters of mothers ≥25 had a ~10% lower risk. Relative weight at age 10 modified the association, with an inverse association between mother's age at delivery and preeclampsia seen only among daughters with low/normal childhood relative weight. In this subset, results were consistent across strata of daughter's age at menarche and age at first birth.
Conclusions
These findings, based on self‐reported data, require replication. Nevertheless, as women increasingly delay childbearing, they provide some reassurance that having been born to an older mother is not, per se, a risk factor for primiparous preeclampsia.