In most cases it's possible for women with prolactinoma to become pregnant, but it may be difficult without the proper treatment. Prolactinoma causes too much prolactin and too little estrogen, which can cause infertility. With the right medications, women may be able to conceive, but it's important to talk to your doctor about plans to become pregnant. This is because the pituitary gland naturally enlarges during pregnancy, meaning that prolactin levels will increase even more and may cause complications. In some cases, tumors may grow and eventually compress the optic nerve, causing headaches and vision problems. Because of this, it's important to check in with your doctor every few months during pregnancy to make sure the tumor is not growing.