Preferred and Actual Interbirth Intervals in Women With Multiple-Partner Fertility

AbstractMothers with multiple-partner fertility have longer interbirth intervals (IBIs) than mothers with single-partner fertility, suggesting that partner change hinders achieving the preferred IBI. Previous studies have, however, overlooked possible differences in preferred IBI between these two groups. Using data from 724 Finnish mothers, we investigated how partner change between the first and second child moderated the association between actual and preferred IBI. Mothers with multiple-partner fertility had 54 months longer IBIs than mothers with single-partner fertility. The association between actual and preferred IBI was weaker in mothers with multiple-partner fertility. Our results further indicated that this difference could partly be explained by the mothers’ deliberate actions, such as contraceptive use and abortions among mothers with multi-partner fertility. Family planning support could gain from mapping out the reasons among women with a partner change for postponing otherwise desired pregnancies and offering increased support in these areas.Keywords: Interbirth intervalsbirth spacingmultiple-partner fertilitypartner changefamily planning Disclosure StatementNo potential conflict of interest was reported by the authors.Data Availability StatementThe data set is available at https://osf.io/bwhpe/.Additional informationFundingThis work was supported by a grant from Sundell’s Foundation to the last author. The funder had no role in the study design or implementation of the study.