What is gigantism?

Gigantism is abnormally large growth due to an excess of growth hormone (GH) during childhood, before the bone growth plates have closed (epiphyseal fusion). It causes excessive growth in height, muscles, and organs, making the child extremely large for his or her age. Other symptoms may include delayed puberty; double vision or difficulty with side (peripheral) vision; prominent forehead (frontal bossing) and a prominent jaw; headache; increased sweating (hyperhidrosis); irregular periods; large hands and feet with thick fingers and toes; thickening of the facial features; and weakness. It may begin at any age before epiphyseal fusion. The most common cause is a non-cancerous (benign) tumor of the pituitary gland, which may cause it to make too much GH, but it can be caused by other underlying conditions (which may cause a pituitary tumor) including Carney complex; McCune-Albright syndrome ; Multiple endocrine neoplasia type 1 (MEN-1) and type 4; and Neurofibromatosis. In some cases the disease is caused by mutations in the GPR101 _gene ._ Treatment typically includes surgery to remove the tumor and can cure many cases. Medication or radiation therapy may be used to reduce GH release or block the effect of GH.

If the condition occurs after normal bone growth has stopped (in adulthood), it is referred to as acromegaly.

Last updated on 05-01-20

Does excess growth hormone have an effect on the uterus, such as causing uterine enlargement and/or myohyperplasia?

We were unable to locate any published reports specifically addressing whether excess growth hormone has an effect on the uterus. However, a study discussing the effect of growth hormone deficiency (but not growth hormone excess) reported findings suggesting that growth hormone deficiency may effect uterus size, because women with isolated growth hormone deficiency or hypopituitarism had smaller uterine measurements than women without these conditions. We were unable to find reports stating that an excess of growth hormone may also effect uterus size, so it is not currently known if this is the case.

Although there is limited information about gigantism and the uterus, there are several reports discussing an association between other conditions that involve pituitary tumors (which have been associated with gigantism) and uterine fibroids. Studies have reported that many patients with acromegaly (a condition similar to gigantism but occurring in adults) have fibroids, and that excess growth hormone may be a cause of fibroids. Another study reported that fibroids of the uterus may be a common symptom of multiple endocrine neoplasia type 1 (MEN1), a condition in which gigantism may occur. These findings do not mean that there is a direct relationship between gigantism and characteristics of the uterus.

While searching all available resources, we were unable to locate information about the relationship between growth hormone and uterine myohyperplasia or myohypertrophy (excessive growth or development of the uterine muscles).

Last updated on 05-01-20

Name: The Pituitary Foundation 86 Colston Street Bristol BS1 5BB
United Kingdom
Phone: 0117 370 1320 Email: Url:

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