Abstract: This updated review includes 38 trials (3326 women). The evidence was very low- to moderate-quality; the main limitations were due to poor reporting of study methods, with downgrading for risks of bias (randomisation and allocation concealment) and lack of blinding. Laparoscopic ovarian drilling with or without medical ovulation induction versus medical ovulation induction alone Pooled results suggest LOD may decrease live birth slightly when compared with medical ovulation induction alone (odds ratio (OR) 0.71, 95% confidence interval (CI) 0.54 to 0.92; 9 studies, 1015 women; I2 = 0%; low-quality evidence). The evidence suggest that if the chance of live birth following medical ovulation induction alone is 42%, the chance following LOD would be between 28% and 40%. The sensitivity analysis restricted to only RCTs with low risk of selection bias suggested there is uncertainty whether there is a difference between the treatments (OR 0.90, 95% CI 0.59 to 1.36; 4 studies, 415 women; I2 = 0%, low-quality evidence). LOD probably reduces multiple pregnancy rates (Peto OR 0.34, 95% CI 0.18 to 0.66; 14 studies, 1161 women; I2 = 2%; moderate-quality evidence). This suggests that if we assume the risk of multiple pregnancy following medical ovulation induction is 5.0%, the risk following LOD would be between 0.9% and 3.4%. Restricting to RCTs that followed women for six months after LOD and six cycles of ovulation induction only, the results for live birth were consistent with the main analysis. There may be little or no difference between the treatments for the likelihood of a clinical pregnancy (OR 0.86, 95% CI 0.72 to 1.03; 21 studies, 2016 women; I2 = 19%; low-quality evidence). There is uncertainty about the effect of LOD compared with ovulation induction alone on miscarriage (OR 1.11, 95% CI 0.78 to 1.59; 19 studies, 1909 women; I2 = 0%; low-quality evidence). OHSS was a very rare event. LOD may reduce OHSS (Peto OR 0.25, 95% CI 0.07 to 0.91; 8 studies, 722 women; I2 = 0%; low-quality evidence). Unilateral LOD versus bilateral LOD Due to the small sample size, the quality of evidence is insufficient to justify a conclusion on live birth (OR 0.83, 95% CI 0.24 to 2.78; 1 study, 44 women; very low-quality evidence). There were no data available on multiple pregnancy. The likelihood of a clinical pregnancy is uncertain between the treatments, due to the quality of the evidence and the large heterogeneity between the studies (OR 0.57, 95% CI 0.39 to 0.84; 7 studies, 470 women; I2 = 60%, very low-quality evidence). Due to the small sample size, the quality of evidence is not sufficient to justify a conclusion on miscarriage (OR 1.02, 95% CI 0.31 to 3.33; 2 studies, 131 women; I2 = 0%; very low-quality evidence). Other comparisons Due to lack of evidence and very low-quality data there is uncertainty whether there is a difference for any of the following comparisons: LOD with IVF versus IVF, LOD with second-look laparoscopy versus expectant management, monopolar versus bipolar LOD, and adjusted thermal dose versus fixed thermal dose. Laparoscopic ovarian drilling with and without medical ovulation induction may decrease the live birth rate in women with anovulatory PCOS and CC resistance compared with medical ovulation induction alone. But the sensitivity analysis restricted to only RCTs at low risk of selection bias suggests there is uncertainty whether there is a difference between the treatments, due to uncertainty around the estimate. Moderate-quality evidence shows that LOD probably reduces the number of multiple pregnancy. Low-quality evidence suggests that there may be little or no difference between the treatments for the likelihood of a clinical pregnancy, and there is uncertainty about the effect of LOD compared with ovulation induction alone on miscarriage. LOD may result in less OHSS. The quality of evidence is insufficient to justify a conclusion on live birth, clinical pregnancy or miscarriage rate for the analysis of unilateral LOD versus bilateral LOD. There were no data available on multiple pregnancy.

Plain-language summary: In this updated review we included 38 controlled trials comparing LOD with medical ovulation induction or comparing different techniques of LOD. The evidence is current to October 2019 Our main analysis with low-quality evidence shows that LOD with and without medical ovulation induction may decrease the live birth rate slightly in women with anovulatory PCOS and CC-resistance compared with medical ovulation induction alone. Analysis including only the higher-quality RCTs shows uncertainty about any difference between the treatments. The evidence suggests that if the chance of live birth following medical ovulation induction alone is 44%, the chance following LOD would be between 32% and 52%. Moderate-quality evidence shows that LOD probably reduces the number of multiple pregnancies. The evidence suggests that if we assume the chance of a multiple pregnancy following medical ovulation induction alone to be 5.0%, the chance following LOD would be between 0.9% and 3.4%. There may be little or no difference between the treatments for clinical pregnancy, and there is uncertainty about the effect of LOD compared with ovulation induction alone on miscarriage. Ovarian hyperstimulation syndrome (OHSS) may occur less often following LOD. The quality of the evidence is not sufficient to justify a conclusion on live birth, clinical pregnancy or miscarriage for the analysis of unilateral LOD versus bilateral LOD. The results of the primary outcomes for the other interventions were insufficient to enable us to draw any conclusions. The evidence was of very low to moderate quality. The main limitations in the evidence were poor reporting of study methods, the presence of bias introduced by the selection of individuals and variability in the results.