RESULTS OF GONADOTROPIN STIMULATION WITH THE OPTION TO CONVERT CYCLESTO IN-VITRO FERTILIZATION IN CASES OF MULTIFOLLICULAR DEVELOPMENT

Background. To avoid a high cancellation rate and/or a high multiple p regnancy rate due to multifollicular development in gonadotrophin stim ulated cycles, such cycles were converted in the same cycle to in vitr o fertilization/embryo transfer (IVF/ET). The results from a four year period using this strategy are summarized. Patients ann methods. Seve nty-three anovulatory women (seven WHO group I, 66 WHO group II) were studied during this period. In a majority of the cycles a GnRH-analogu e was used for down-regulation according to a long protocol, followed by stimulation with FSH and/or hMG. Results. Out of 154 WHO group II g onadotrophin stimulation cycles intended for ovulation induction, 25 c ycles were converted to IVF. The pregnancy and delivery rates in the I VF-converted cycles were 50% and 41%, respectively, and 31% and 22% wh en gonadotrophin stimulation was followed by intercourse. The cancella tion rate, including both ovulation induction and IVF cycles, was 15% and the multiple pregnancy rate was 30%, mainly twins. Lean women achi eved better outcome than obese women. In WHO group I only 12 cycles we re performed. One cycle was converted to IVF resulting in delivery and one cycle was cancelled. The pregnancy-and delivery rates were both 5 0% when gonadotrophin stimulation was followed by intercourse. Conclus ion. It is concluded that the option to convert a gonadotrophin stimul ation cycle to IVF in the same cycle, in cases of multifollicular deve lopment, seemed to be a good alternative. The conversion results in a low cancellation rate and a low incidence of high order multiple pregn ancies. Patients should be informed of this opportunity before enterin g ovulation stimulation.