Four months pregnant husband wants to have sex every day may have an effect, may cause contractions, leading to miscarriage, uterine cavity infection, etc.. Women are not allowed to have sex in the first three and second three months of pregnancy, which can easily affect the fetus. In the middle of pregnancy, you can have sex appropriately, but not too often. Already four months pregnant, not every day sex, moderate can be about 2 times a week sex. If sex is more frequent, the action is more rough, stimulate the cervix, it is easy to cause contractions, stimulate the uterus, induced miscarriage or premature labor phenomenon. Frequent sexual intercourse without paying attention to hygiene may also cause infection in the uterine cavity, jeopardizing the health of mother and fetus. If you have irregular vaginal bleeding during pregnancy, go to the obstetrics and gynecology department of the hospital in time.