Large motherhood penalties in US administrative microdata

Whereas previous research has described motherhood penalties in US survey data, we leverage administrative data on 811,000 quarterly earnings histories from the US Unemployment Insurance program. We analyze contexts where smaller motherhood penalties might be expected: couples where the woman outearns her male partner prior to childbearing, at firms that are headed by women, and at firms that are predominantly women. Our startling result is that none of these propitious contexts appear to diminish the motherhood penalty, and indeed, the gap often increases in magnitude over time following childbearing. We estimate one of the largest motherhood penalties in "female-breadwinner" families, where higher-earning women experience a 60% drop from their prechildbirth earnings relative to their male partners. Turning to proximate mechanisms, women are less likely to switch to a higher-paying firm postchildbearing than men and are substantially more likely to quit the labor force. On the whole, our findings are discouraging relative even to existing research on motherhood penalties.