Fig. 3
Serum P4 and E2 contents on Days 4 and 4.5 of pregnancy. The levels of P4 and E2 were determined. a Serum E2 content showed significant differences on both day 4 (59.68 ± 8.59 pg/ml vs. control 16.71 ± 1.48 pg/ml; P < 0.05) and day 4.5 (33.62 ± 5.34 pg/ml vs. control 12.16 ± 1.49 pg/ml; P < 0.5). Data are expressed as the means ± SEM (N = 9) Different superscript letters indicate statistically significant differences (P < 0.05). b No significant difference was found in serum P4 content between the control group and melatonin group on day 4 (9.12 ± 1.31 ng/ml vs. control 8.27 ± 0.73 ng/ml; P > 0.05) and day 4.5 (18.82 ± 2.31 ng/ml vs. control 17.76 ± 2.05 ng/ml; P > 0.05)