The mainstay in management of ovulation problem in overweight women with PCOS is weight loss. Lack of ovulation in normal weight women is treated initially with up to six cycles of clomiphene citrate (Clomid®). This acts by blocking the oestrogen receptors in the pituitary gland, which in turn increases the levels of follicle stimulating hormone (FSH). FSH promotes follicle recruitment and development within the ovary.
The first cycle of treatment with clomiphene should be monitored with ultrasound scan to confirm follicular response to treatment and to reduce the risk of multiple pregnancy (6%). If there is an over response to the treatment and more than 2 follicles are produced the treatment cycle should be abandoned. Clomid should not normally be used for more than 9-12 cycles because of the very limited benefits which have to be balanced against the small risk of ovarian cancer with prolonged exposure.
Some women with PCOS don’t respond to clomiphene. In these cases alternatives include: ovarian drilling which involves making four small holes in the ovary using a needle that carries electricity (diathermy) performed at the time of laparoscopy (keyhole surgery), gonadotrophins (FSH/LH) injections alone or in an assisted conception programme (intrauterine insemination — IUI or in vitro fertilisation — IVF).
Ovulation induction with gonadotrophins should be carried out in a specialist fertility centre. Investigations on behalf of both partners to exclude other co-existing causes of infertility should be considered before starting treatment. Women receiveing gonadotrophin injections must be monitored closely with serial trasnvaginal ultrasound scans (and sometimes blood tests) to ensure that only one or two follicles are developing in the ovaries. This is very important to minimise the risk of multiple pregnancy and ovarian hyperstimualtion syndrome (OHSS).It may be difficult to achieve an optimal response (one or two follicles) in some women while others may not respond at all. In such cases women will be advised to move on to IVF treatment.
IVF is generally successful in women with PCOS. Success rates are similar to those achieved for couples with other causes such as tubal disease or male factor. Women with PCOS are generally at increased risk of OHSS and therefore caution should be taken to minimise the risk of OHSS during IVF treatment.