The transition to parenthood brings changes in many areas of life, including the area of sexuality. The aim of this study was to examine differences in the frequency of sexual intercourse, sexual satisfaction and the sexual self-schema of participants in different stages of their transition to parenthood. The study involved men and women without children, those who were expecting their first child, and parents of six-month-old and one-year-old children (N = 650). The results showed that participants in different stages of transition to parenthood differed in the frequency of sexual intercourse, but not in their sexual satisfaction and sexual self-schema. Men and women without children and parents of one-year-olds reported more frequent sexual intercourse than those expecting their first child and parents of six-month-old children, although these differences were statistically significant only in the female sample. Men, compared to women, reported more frequent sexual intercourse and greater sexual satisfaction. The research results demonstrate the complexity of sexual functioning during the transition to parenthood and can be applied in providing psychosocial support during this period of life.