Aim:
To determine the cumulative pregnancy rate, multiple pregnancy rate, incidence of cancelled cycles and incidence of ovarian hyper-stimulation syndrome (OHSS) for therapy naive women undergoing ovulation induction (OI) with gonadotrophins.
Method:
A retrospective analysis of therapy naive patients undergoing OI with gonadotrophins was performed over a 3 year period across 2 fertility centres. Patients with oligo- or anovulation underwent OI with follicle stimulating hormone (FSH) or FSH and luteinising hormone (LH) if required, via low dose step-up protocol. Pelvic ultrasound, serum estradiol and LH measurements were used for follicle tracking. Pregnancy was diagnosed with serum hCG measurement at 14 days and clinical pregnancy confirmed with pelvic ultrasound.
Demographic data including parity, age, BMI, AMH and partner’s age and BMI were recorded. Number of cycles, dose of FSH, number of increases of doses and final dose was recorded for each cycle. The outcome of each cycle, reason for cancellation if cancelled, and incidence of multiple pregnancy or OHSS was recorded.
Results:
268 patients underwent 591 cycles of OI during the study period. Mean number of cycles per patient was 2.2 (min =1, max=7). 85 cycles were cancelled, a rate of 14.3% of all cycles; the reasons for cancellation were; too many follicles (42% of cancelled cycles), no response (31%), missed ovulation (9%), patient away or partner away.
The pregnancy rate per cycle was 22% for cycle 1 (42% of the total clinical pregnancies), 17.8% for cycle 2 (33.8% of the total clinical pregnancies), 7.4% for cycle 3 (14% of the total clinical pregnancies), with a pregnancy rate of below 2.5% for each cycle thereafter.
Indicators for success included normal range BMI, higher AMH and younger age of patient. These findings were significant for age (under 35) and BMI (under 25), p<0.05.
136 patients had a clinical pregnancy, a rate of 51%. 94 off these resulted in a live birth, 26 were ongoing at time of reporting, 16 resulted in miscarriage and 1 was an ectopic pregnancy.
5 of the clinical pregnancies were multiple pregnancies, (all DCDA), a rate of 2% for all patients and 3.6% for all clinical pregnancies. No higher order pregnancies occurred.
No cases of OHSS were seen.
Conclusion:
OI with gonadotrophin therapy is a safe, effective option for therapy naive patients. It has a multiple pregnancy rate that compares very favourably with IVF, without the risk of OHSS. Rate of success drops substantially after 3 cycles.