Sari van Anders, an assistant professor of psychology and women's studies at the University of Michigan in Ann Arbor, said these changes in sexual desire were linked to social factors, or factors related to raising a child, rather than physical changes resulting from the birth itself, liveScience reported.
The study, published in the Journal of Sexual Medicine, found the most common reasons partners gave for their low sexual desire in the post-partum period were: fatigue, stress, too little time and baby's sleeping habits. However, vaginal bleeding from the mothers and breastfeeding, ranked lower, the study found.
Conventional wisdom presumes hormonal changes or vagina concerns explain the birth mothers' lack of interest in sexuality, and that their partners can't wait to have sex, van Anders said.
The researchers analyzed data from 114 partners -- mostly men, but also some women -- of women who had given birth in the past seven years.
Van Anders said many doctors recommend delaying sex for four to six weeks after childbirth to allow the cervix to close, bleeding to stop and any vaginal tears to heal, but the research suggested individuals are engaging in a range of sexual behaviors before that.
About one-third of partners said they had engaged in sexual intercourse with the birth mother within six weeks of childbirth, while about one-third of partners said they had performed oral sex on the birth mother within six weeks of childbirth.