(A) Experimental time line. (B) Corticosterone concentrations were measured in serum samples from tail vein blood immediately before and after stress sessions on days 1, 11, and 18. (C) Total reproductive success was measured as percentage of females that successfully brought a litter to full term (Scramble/control N = 17, Scramble/Stress N = 14, shRNA/control N = 20, shRNA/stress N = 14, g-statistics: G = 5.836, df = 1 p = 0.016, fisher's exact test p = 0.0031). Breaking down total reproductive success, (D) copulation success was measured as percentage of females that exhibited lordosis and allowed a male to achieve intromission within 15 min (g-statistics: G = 2.405, df = 1 p = 0.028, fisher's exact test p = 0.0062), and (E) pregnancy success refers to the percentage of females that got pregnant out of the subgroup that successfully copulated (Scramble/control N = 15, Scramble/Stress N = 6, RFRP-shRNA/control N = 18, RFRP-shRNA/stress N = 11). (F) Litter sizes measured as number of pups born alive immediately after birth (dams-Scramble/control N = 13, Scramble/Stress N = 3, RFRP-shRNA/control N = 16, RFRP-shRNA/stress N = 9). (G) Embryos implanted measured as number of placental scars identified in the dam's uterine horns after birth. (H) Embryo survival was calculated as the number of birthed pups divided by number of maternal placental scars and shown as a percentage (indicative of initial implantation, mean ± SEM) *p < 0.05, **p < 0.01, ***p < 0.001. Reproductive success statistics were done by G-statistics tests followed by Fisher's Exact test, statistics for litter size, placental scars, and embryo resorption were done by a two-way analysis of variance (ANOVA) followed by Bonferroni post-hoc tests and CORT statistics analyzed by a repeated two-way ANOVA.