Ovulation occurs each month when a mature egg is released from the ovarian follicle. This is the result of a complex series of hormonal interactions, known as the hypothalamic pituitary adrenal axis. The term anovulation means no ovulation and oliogoovulation denotes irregular ovulation

During the monthly cycle, the hypothalamus stimulates the pituitary to increase production of the hormone FSH. FSH stimulates the recruitment and development of eggs within the ovarian follicles. As the follicles develop, they began producing the hormone estrogen and as estrogen levels rise the hypothalamus signals the pituitary to reduce the levels of FSH. Once the eggs are mature the hypothalamus signals the pituitary to release a surge of luteinzing hormone which causes the egg(s) to be ovulated, or released, from the ovarian follicle(s).

After release, the egg travels through the fallopian tubes to the distal end where fertilization occurs. The remaining follicle becomes a structure known as the corpus luteum and it begins to produce progesterone to help support the endometrium.

There are many reasons why a woman may not ovulate or she may ovulate irregularly. Most of these conditions can be treated successfully .

How Does Failed Ovulation Occur?

Hormone imbalance - FSH must be released to stimulate the development of the ovarian follicles.
Overweight
Stress
Ovarian problems, such as a tumor or cyst.
Short menstrual cycle.
Weight loss for various reasons, including eating disorders such as anorexia and bulimia
Abuse of alcohol or drugs.
Thyroid gland problems.

How is ovulatory failure treated?

First line treatments for ovulatory failure include medications such as Clomid and FSH. Clomid competes with estrogen receptors at the hypothalamus causing it to signal increased production of FSH. Clomid is administered for three ovulatory cycles, and if it is unsuccessful, FSH is usually the next step. Dependent upon the patient's diagnosis, FSH will be combined with intrauterine insemination for three cycles.

Sometimes elevated prolactin levels may cause ovulatory failure. Prolactin is the hormone responsible for stimulating breast milk production in pregnancy. Abnormally high levels are usually caused by a benign tumor in the brain which may be removed or treated with the medication.

Lifestyle modification is recommended for overweight or anorexic patients. PCOS will be ruled out and is common in overweight patients. Weight loss can be very difficult for patients with polycystic ovarian syndrome.

Robert B. McWilliams, MD Reproductive Endocrinology and Gynecology

Ovulation

How Does Failed Ovulation Occur?

How is ovulatory failure treated?

Robert B. McWilliams, MD
Reproductive Endocrinology
and Gynecology