Women who breastfeed can resume having sex just as soon as women who do not breast-feed. New mothers, however, may notice a dryness of the vagina that can cause pain during sex. This condition often lasts longer in a woman who nurses. A special cream or jelly can provide the vaginal lubrication you need. 

Many people believe that nursing mothers cannot get pregnant. It is true that the return of ovulation (the release of an egg from the ovary each month) and menstruation may be delayed if a woman is nursing. But, ovulation will often occur before you begin having periods again. Even though breast-feeding women are less likely to become pregnant, do not think of breast-feeding as a form of birth control. 

A number of contraceptives can be used safely by women who breastfeed. Talk with your health care provider about what form of birth control is right for you. Women who previously relied on periodic abstinence, or natural family planning, should be aware that ovulation is harder to detect during breastfeeding.