Fertility is not guaranteed even for adults with a gland normal pituitary (10% of “normal” couples are infertile). The hypopituitarism-related infertility is the result of a deficit of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Sometimes if prolactin levels are high, determines a decrease of FSH and LH.
Deficiency of LH and FSH, together referred to as the gonadotropins, leads to different symptoms in men and women. Women experience oligo- or amenorrhea (infrequent/light or absent menstrual periods respectively) and infertility because correct LH:FSH ratio is essential for number of mature follicles, retrieved oocytes, oocytes maturity, quality of embryo, and pregnancy rate.
Clinically significant elevation of prolactin levels may cause infertility in several different ways. First, prolactin may stop a woman from ovulating. If this occurs, a woman’s menstrual cycles will stop. In less severe cases, high prolactin levels may only disrupt ovulation once in a while. This would result in intermittent ovulation or ovulation that takes a long time to occur. Women in this category may experience infrequent or irregular periods. Women with the mildest cases involving high prolactin levels may ovulate regularly but not produce enough of the hormone progesterone after ovulation. This is known as a luteal phase defect. Deficiency in the amount of progesterone produced after ovulation may result in a uterine lining that is less able to have an embryo implant. Some women with this problem may see their period come a short time after ovulation.
Hyperprolactinemia in men may result in as a first signs of decreased libido or impotence, however also cause inefficient sperm production and infertility.
Both sexes may experience a decrease in libido and loss of sexual function. Lack of LH/FSH in children is associated with delayed puberty. Women normally have normal number of eggs within their ovaries so fertility can be achieved relatively quickly using proper treatment. Men need treatment to stimulate sperm production and it can take up to 24 months.