Metformin belongs to a class of fertility drugs known as antihyperglycemics and it is used to treat Type II diabetes. These patients are hyperinsulinemic meaning they have abnormally elevated levels of insulin. Metformin increases the pancreatic cells sensitivity to insulin thus lowering insulin levels and reversing hyperinsulinemia.
When a patient is “insulin resistant” it means that her body tries to compensate for lower insulin levels by overproducing insulin. When the cells are “sensitized” to insulin (increased sensitivity) by Metformin, circulating levels of insulin decline.
Polycystic ovarian syndrome (PCOS) patients often have chronically elevated insulin levels (hyperinsulinemia) leading to overproduction of androgens (male hormones) by the ovaries, increased LH production, often obesity, ovaries covered with many unruptured cysts, excess body or facial hair, irregular or no ovulation, and infertility. If abnormally elevated insulin levels are corrected, ovulation will often resume. This is because when insulin levels decline the ovary reduces it production of androgens.
PCOS patients can suffer serious long term health consequences of chronically elevated androgen levels. Oftentimes they have a significantly increased risk of cardiovascular disease and diabetes. For this reason, some specialists choose to administer Metformin to PCOS patients “long term” in addition to acute treatment for infertility.
Metformin differs from Clomid and FSH in that it does not directly stimulate ovulation rather it corrects a physiologically abnormal condition (chronic hyperinsulinemia) thus allowing natural ovulation to resume. Metformin can be used as “solo” therapy or combined with FSH, Clomid or letrozole (Femara). Some studies have shown PCOS patients respond better to Metformin and Clomid better than Clomid alone. The usual dose of Metformin is 850 mg. twice a day or 500 M.G. 3 or 4 times a day. Because of the complexity of the disease, PCOS patients needing ovulation induction can optimally be managed by a reproductive endocrinologist.