Ultrasound for monitoring controlled ovarian stimulation: a systematic review and meta-analysis of randomized controlled trials

Abstract

Objective: To evaluate the efficacy and safety of monitoring controlled ovarian stimulation (COS) using ultrasonography.

Methods: We performed a search in April 2013 for randomized controlled trials (RCTs). Studies that compared different methods for monitoring COS, including ultrasound assessment of follicles (alone or combined with hormonal assessment), in at least one group were considered eligible.

Results: The search retrieved 1515 records, six of which were eligible. Five studies were included that compared ultrasonography alone with ultrasonography and hormonal assessment (estradiol and/or progesterone) and one study compared 2D and 3D ultrasound monitoring. None of the included studies reported on live birth. Four of the five studies reported on clinical pregnancy (RR, 0.95; 95% CI, 0.78–1.16; n = 611); the confidence interval (CI) was somewhat wide, but allowed us to conclude that ultrasonography alone differs little from ultrasonography combined with hormonal assessment. Three studies reported on the number of oocytes retrieved (mean difference (MD), 0.8 oocytes; 95% CI, –0.4 to 2.0; n = 474); the CI was somewhat wide and did not permit us to conclude whether ultrasonography alone is better than or similar to ultrasonography and hormonal assessment for this outcome. All five studies reported on ovarian hyperstimulation syndrome (OR, 1.02; 95% CI, 0.47–2.25; n = 725) and only one study reported on miscarriage (RR, 0.37; 95% CI, 0.07–1.79; n = 45); for these two outcomes, the CI was very wide and did not permit us to conclude whether ultrasonography alone is better, similar or less effective than ultrasonography combined with hormonal assessment. For the study comparing 2D and 3D ultrasound, the reported outcomes were clinical pregnancy (RR, 1.00; 95% CI, 0.58–1.73, n = 72) and the number of oocytes retrieved (MD, –0.4 oocytes; 95% CI, –3.6 to 2.9; n = 72); for both, the CI was very wide and did not permit us to conclude whether use of 3D ultrasound is better, similar or less effective than use of 2D ultrasound.

Conclusions: Current evidence suggests that monitoring COS only with ultrasonography is unlikely to substantially alter the chances of achieving a clinical pregnancy and the number of oocytes retrieved is similar to that when monitoring with ultrasonography and hormonal assessment. For the other outcomes and comparisons, the available data are inconclusive. We believe that more studies evaluating the optimal procedure for monitoring COS are needed.