Increased blood flow to the vagina, which swells the walls of the vaginal canal, can create a feeling of tightness and make penetration hurt. Cramping with lower belly pain, a symptom known as round ligament pain, can start in the 14th week and get more severe as your pregnancy progresses. As pregnancy progresses and women's bodies change, many once beloved sexual positions are no longer comfortable Researchers with the University of California San Francisco found that two years after childbirth, there was no notable link between having a baby and subsequent low desire, sub-monthly sexual activity or low overall sexual satisfaction. It typically begins in the second trimester, she explained, adding that it can be difficult for a woman's partner to adjust to the idea that her breasts are not simply there for sexual pleasure. It seems just a tad obvious, but studies are only just beginning to show that having a child affects partners' sexual desire, as well. And that could lead to an overall boost in couple-wide randiness, if you will. It could also be due to chronic condition like endometriosis. The dryness, she explained, results from a lack of estrogen, particularly among women who breastfeed. Indeed, roughly 40 percent of women reported they masturbated within the first few weeks of having a baby. Sexual activity won't affect your baby, as long as you don't have complications such as preterm labor or placenta problems. When should I go to the doctor with pain during sex? View Sources. Even the most sexually confident woman might wonder: This thing that's happening here, is that normal?