Grant: Op Grant: Data Analysis - Reproductive, Maternal, Child and Youth Health

Purpose: Closely spaced pregnancies have poor maternal and infant outcomes. Existing guidelines recommend waiting from at least 18 to 24 months following previous childbirth until becoming pregnant again. It is not known, however, whether these guidelines suitable for all women. Women with a prior history of poor outcomes might have different optimal interpregnancy interval pertinent to them and waiting for 18 months might be associated with adverse outcomes. For example, among women who had pregnancy loss, current recommendations to wait 18 months before their next pregnancy may prolong their grief and emotional stress, whereas for women with a history of subfertility, waiting the recommended 18 months may increase their risk of infertility due to advancing maternal age. In this project, we will study whether associations between short intervals and adverse outcomes are the same or different among women with poor outcomes in the first pregnancy (fetal or newborn death, history of infertility treatment, or preterm delivery) and among women without poor outcomes in the first pregnancy. This will help us to create guidelines on optimal birth spacing for women with the poor outcomes in their first pregnancies. Methods: We will use a high-quality, population-based cohort including all pregnancies in British Columbia from 2004 to 2014 to examine relationships between pregnancy spacing interval and adverse outcomes (fetal or newborn mortality, poor fetal growth, preterm delivery) for women with a fetal or newborn death, infertility treatment, or preterm birth in the first pregnancy. Impact Study findings will inform women's and families' pregnancy spacing decisions to achieve the best pregnancy outcomes they can. These findings will guide clinicians providing counselling on optimal pregnancy spacing for women in these high-risk groups.