Ovulation induction and monitoring of treatment cycles

Hormonal medications are administered to stimulate the ovaries in such a way that several follicles develop. Doses my be adjusted during the cycle, depending upon follicle growth. Several methods of ovulation induction are used, depending on which method is suitable for the patient, according to the physician's judement. The combination of GnRH-a and gonadotrophins is currently the most frequently used method for stimulating the ovaries.

Careful monitoring will prevent the development of too many eggs and will thus reduce the chance of multiple pregnancies and the development of ovarian hyperstimulation syndrome.

Monitoring can be performed in two ways:

• by endocrine assay of the blood levels of estrogen, LH and progesterone.


• by ultrasound scanning using the modern technique of vaginal ultrasound which does not require the bladder to be full. Using ultrasound, a picture of the ovaries, follicles, and state of the lining of the uterus can be obtained.

When the follicular development has reached the stage when an optimum number of eggs will be produced without untoward effects, hCG will be administered to trigger ovulation. Egg retrieval is normally scheduled 34 to 36 hours after hCG administration.