Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are two hormones responsible for ovulation. Very high or low body weight can disrupt these hormones and may result in infertility. The production of FSH and LH is increased by gonadotropin releasing hormone (GnRH), which stimulates their production from the pituitary gland.

Low Body Weight

For women, low weight can decrease production of GnRH. This can cause ovulation to become irregular or even stop. To maintain normal ovulation, body fat should be at least 22% of body weight. For men, low weight could lead to decreased sperm count.

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Being overweight can also lead to abnormal hormonal signals, impacting ovulation. It can affect the production of insulin, which may cause irregular ovulation. There is a link between obesity, insulin resistance and the  condition known as polycystic ovarian syndrome (PCOS).

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What To Do

A healthy return to normal body weight may help to restore fertility.

Normal body weight is also a healthy preparation for pregnancy. If the cause of obesity is related to PCOS, the use of insulin sensitizing drugs may be needed as well as dietary changes.

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