Abstract
Summary A new approach is suggested for assessing the relationship between birth order and pregnancy risk. Population data are used to estimate the risk of a poor pregnancy outcome after different reproductive histories. The risk of a poor outcome at the first pregnancy appears to be twice that at subsequent pregnancies, but no change in risk is observed between the second and fifth birth orders. If there has been a previous poor pregnancy outcome, the risk of another is increased four-fold.

This publication has 18 references indexed in Scilit: