Health Influences on Second‐ and Third‐Birth Probabilities in Norway

We examined how several health variables were associated with mothers’ probability of having a second or third child and the timing of the second birth. Data from the Norwegian Mother, Father and Child Cohort Study (MoBa) and linked registers were used. Parents with certain potentially chronic health problems before or in pregnancy were less likely than others to have an additional (especially a second) child, net of differences in relationship status, education, and economic resources. Some pregnancy‐related and largely temporary health problems during the most recent previous pregnancy and adverse birth experiences were associated with reduced probabilities of a second or third birth, or both, as was generally poor physical health six months after birth and postnatal depression. The latter health indicators may reflect health implications of pregnancy, delivery, and having a relatively “demanding” young child, as well as underlying health problems. Only a few estimates suggested associations between indicators of potentially chronic health problems of the most recently born child and subsequent fertility, but fertility was reduced among one‐child mothers whose first child had colic and among one‐ and two‐child mothers whose most recently born child slept little. Possible reasons for and implications of these health–fertility associations are discussed.