The effect of pregnancy and lactation on the sexual behavior of women was studied, using a retrospective questionnaire answered by a nonrandom sample of 33 women. Sexual functioning was operationally defined by four categories: desire, frequency, enjoyment, and orgasm. Five time periods were studied: the three trimesters of pregnancy, the period of breastfeeding and the period after weaning. Most of the mothers reported that their sexual behavior was “about the same” during pregnancy as before except for the third trimester, where desire, frequency, and enjoyment decreased. Eighty-two percent of the mothers felt that sex relations should continue throughout all of the pregnancy. Sexual functioning during breastfeeding was reported to be “about the same” as before pregnancy by 75% of the women. Desire returned for most women by 4 weeks after childbirth, earlier than many of them felt it safe to resume sex relations. Women who had been married longer, with more children and more breastfeeding time, reported an earlier return of sexual interest and felt it safe to resume sex relations earlier. Most women reported their sexual interest after weaning was “about the same.” No one reported a decrease in sexual interest after weaning. All of the women reported breastfeeding to be enjoyable. Younger marrieds were apt to rate breastfeeding even higher than older marrieds. Also, younger marrieds felt freer about breastfeeding in public. Sexual relations continue when procreatively unfruitful and even when difficult in humans. This underscores the importance of the bonding value of sex.