Where problems may arise

Problems may arise at several stages in the IVF cycle:

1. The treatment cycle may be cancelled for any of the following reasons:

• ovulation induction did not produce enough stimulation of the ovaries or less than three follicles fail to develop
• hormone levels fail to show a satisfactory rising pattern
• hormone levels fall before follicles have completely developed
• there is an excessive response (more than 15 follicles)
• ovulation occurs unexpectedly before admission to the hospital, which means it is impossible to properly time the procedure (such incidence is rare)

2. Egg pick-up may be unsuccessful and no eggs recovered.

3. Eggs are recovered but fail to fertilize.

4. Embryos are transferred to the uterus but fail to implant, resulting in a period seven to 14 days later.

5. Like natural conception, IVF can lead to:

• biochemical pregnancy (transient rise in pregnancy hormone followed by late period)
• miscarriage (needing uterine cotterage)
• ectopic pregnancy (requiring surgery)

6. Multiple pregnancy (twins, triplets, etc.) is more common with IVF than with natural conception because of the practice of transferring more than one embryo to the uterus. In general, the success rate is higher if more than one embryo is transferred. However, the maximum number of embryos transferred is normally limited to three.