Abstract: Four RCTs were included in the review (416 women). The trials compared glucocorticoid supplementation during IVF stimulation versus placebo. Two of the studies had data in a form that we could not enter into analysis, so results include data from only two trials (310) women. For the outcome of live birth, data were available for only 212 women, as the larger study had data available from only one study centre. One of the studies gave inadequate description of randomisation methods, but the other was at low risk of bias in all domains. The evidence was rated as low or very low quality for all outcomes, mainly due to imprecision, with low sample sizes and few events. There was insufficient evidence to determine whether there was any difference between the groups in live birth rate (OR 1.08, 95% CI 0.45 to 2.58; 2 RCTs, n = 212, I2 = 0%, low-quality evidence). Our findings suggest that if the chance of live birth with placebo is assumed to be 15%, the chance following supplementation would be between 7% and 31%. There was no conclusive evidence of a difference in the clinical pregnancy rate (OR 1.69, 95% CI 0.98 to 2.90; 2 RCTs, n = 310, I2 = 0%, low-quality evidence).The evidence suggests that if the chance of clinical pregnancy with placebo is assumed to be 24%, the chance following treatment with glucocorticoid supplementation would be between 23% and 47%. There was also insufficient evidence to determine whether there was any difference between the groups in multiple-pregnancy rate (OR 3.32 , 95% CI 0.12 to 91.60; 1 RCT , n = 20, very low-quality evidence) or miscarriage rate (OR 1.00, 95% CI 0.05 to 18.57; 1 RCT, n = 20, very low-quality evidence). Neither of the studies reported OHSS or side-effects. The safety and effectiveness of glucocorticoid administration in women undergoing controlled ovarian hyperstimulation for IVF/ICSI cycles (until the day of oocyte retrieval) is unclear due to the small number of studies and low event rates. Whilst glucocorticoids possibly increase the clinical pregnancy rate, there may be little or no impact on live birth rate. More research is needed.

Plain-language summary: We found four randomised controlled trials (RCTs), but useable data were available for only two of these. The trials compared adjuvant treatment with systemic glucocorticoids during ovarian stimulation for IVF cycles versus no placebo. The evidence is current to October 2016. Key results Two RCTs were included in our analyses (310 women). For the outcome of live birth, data were available for only 212 women, as the larger study had data available from only one study centre. There was no conclusive evidence of a difference in the primary outcome of live birth rate and the secondary outcome of clinical pregnancy rate. Our findings suggest that if the chance of live birth with placebo is assumed to be 15%, the chance following supplementation would be between 7% and 31%, and that if the chance of clinical pregnancy with placebo is assumed to be 24%, the chance following treatment with supplementation would be between 23% and 47%. There was also insufficient evidence to determine whether there was any difference between the groups in the multiple-pregnancy rate or miscarriage rate. Neither of the studies reported ovarian hyperstimulation syndrome (OHSS) or side-effects. Thus, the safety and effectiveness of glucocorticoid administration in women undergoing controlled ovarian hyperstimulation for IVF/ICSI cycles (until the day of oocyte retrieval) is unclear due to the small number of studies and low event rates. Whilst glucocorticoids possibly increase the clinical pregnancy rate, there may be little or no impact on the live birth rate. The evidence was rated as low or very low quality for all outcomes, mainly due to imprecision, with low sample sizes and few events.