The reason is because men can't have children, and giving birth to children is a woman's business;

The whole process of giving birth is divided into three stages, also known as three stages of labor. The first process of giving birth to a child, that is, the period of uterine dilatation. The second process of giving birth, that is, the delivery period of the fetus. The third process of giving birth, the period of placenta delivery.

Extended data:

When the fetus is about to be born, due to the expansion of perineum and vulva, the parturient will also feel burning sensation and intense pain in these parts. Finding a comfortable position and taking deep breaths in a relaxed state can relieve the pain of childbirth.

The pain caused by uterine contraction will run through the whole process of giving birth. Contraction pain mainly occurs in the lower abdomen, and sometimes also occurs on the inside of two strands or above the spine. Most women feel uterine contraction pain similar to menstrual cramps, but more intense.

Be fully prepared for the pain of giving birth. Childbirth is a natural physiological phenomenon, and childbirth pain is physiological pain, which can be tolerated by most people. However, childbirth must go through a period of severe pain. If there is no adequate mental preparation, pregnant women will be crushed by unexpected pain.

Baidu encyclopedia-childbirth