Ovulation induction, or ovarian stimulation, is a way of assisting women who do not ovulate and need medical treatment to stimulate ovulation. It is also recommended for women who have Polycystic Ovary Syndrome (PCOS).

Who is it recommended for?

  • For women whose periods are irregular as a result of too little or an unbalanced production of FSH (follicle stimulating hormone) or LH (luteinizing hormone). These women require help to ovulate regularly and develop follicles to maturity.
  • For women with PCOS – a chronic condition in which the ovaries develop tiny cysts, caused by egg follicles that have not matured properly. It is accompanied by a low level of progesterone and a high level of LH. These make it difficult for eggs to mature and release

How do the drugs work?

Various medications are given to stimulate the growth of the oocytes (eggs). The drug used in Ovulation Induction is clomiphene citrate, eg Clomid, Fertomed, Clomihexal or fertility injections containing FSH, eg Gonal-F and Menopur.

The drug clomiphene binds to estrogen receptor sites in the brain, tricking the hormone), encouraging the pituitary gland to release more FSH and LH. This then causes a follicle to start maturing an egg ready for ovulation.

Ovulation induction can also be triggered by an injection of HCG (human chorionic gonadotrophin), eg Ovidrel and Pregnyl. This drug encourages the final maturation of the follicle and release of the egg. This is used to decide exactly when intercourse should occur.

Regular monitoring of women taking these drugs is essential. Ultrasound scans check the number and development of follicles in the ovaries.

Are there any side effects?

Clomiphene may cause hot flushes and headaches. Some women also have weight gain and breast tenderness.