The secondary outcome measure is endometrial thickness. A previous study reported that the mean (±SD) total number of follicles was 5.1 (±0.41) follicles for the early CC protocol compared with 2.8 (±3.1) follicles for the late CC protocol (Badawy et al., 2009). The same study of Badawy et al (2009) reported that mean (±SD) number of follicles > 14 mm in diameter was 3.0 (±0.28) follicles and 1.5 (±0.18) follicles in the early CC and late CC protocols, respectively. The mean (±SD) number of follicles > 18 mm in diameter was reported to be 2.1 (±0.15) follicles and 1.3 (±0.32) follicles in the early CC and late CC protocols, respectively. As regards the endometrial thickness at hCG administration, the mean (±SD) thickness was 9.1 (±0.23) mm versus 8.2 (±0.6) mm for the early CC and late CC protocols, respectively.