Womb at work: the missing impact of maternal employment on newborn health

Parental leave policies across the globe have become much more generous than they used to be. This is also true for prenatal maternal leave. While this may be costly in the short run, little is known about the effect of maternal employment during pregnancy on newborn health. In this paper, I exploit three sharp policy changes on the duration of paid parental leave in Austria that strongly affected the share of mothers who work up to the 32nd week of pregnancy. I use administrative data from Austria on the working history of women linked to the full Austrian birth register and coupled with a regression discontinuity framework to identify the effect of prenatal employment on their offspring. Maternal employment during pregnancy with the second child reacts strongly to these policy changes. The share of employed mothers sharply declined in 1990 by 19.1 percentage points, increased in 1996 by 7.2 percentage points and declined again by 6.4 percentage points in 2000. None of these changes in prenatal employment translated into effects on newborn health measured via birth weight, gestational length, and Apgar scores. This result holds true for mothers of different socioeconomic backgrounds and across industries. The effect is precisely estimated, which suggests that prenatal employment prior to the 32nd week of pregnancy does not causally affect the fetus for measures visible at birth.