Causes of pituitary amenorrhea

Pituitary amenorrhea is caused by organic lesions or dysfunction of the pituitary gland, which affects the secretion of gonadotropin and thus affects ovarian function, causing amenorrhea.

Organic pituitary lesions

There are three types of organic pituitary lesions: the enlargement of pituitary tumors can compress cells that secrete gonadotropin; after pituitary radiotherapy or surgery, brain trauma, intracranial inflammation, etc. can damage pituitary tissue; postpartum hemorrhage can cause pituitary blood supply obstruction and ischemic necrosis. These three reasons can reduce the secretion of gonadotropin by the pituitary gland and cause amenorrhea.

Pituitary tumors can occur inside or outside the sella turcica, and can cause amenorrhea, sexual dysfunction, and other related symptoms such as visual field impairment, headache, lactation, and acromegaly due to mechanical compression or abnormal function of the tumor itself. Pituitary tumors occurring before puberty can cause primary amenorrhea, which is caused by dysfunction due to damage to the pituitary gland. This is more common in cases of postpartum hemorrhage with shock, severe postpartum infection, or disseminated intravascular coagulation, which can lead to ischemic necrosis of the anterior pituitary gland, followed by hypofunction and amenorrhea.

Primary pituitary dysfunction

This situation is relatively rare clinically. The patient has primordial follicles in the ovaries, but due to low secretion of gonadotropin by the pituitary gland, the follicles cannot grow and develop. The amenorrhea is primary amenorrhea. At the same time, the internal and external reproductive organs are immature, the secondary sexual characteristics are not developed, the intracellular sex chromatin is positive, and the karyotype is 46XX. Treatment with gonadotropin is effective.