GD18 pup weights (A), average litter size by fetal number (B), placental efficiency (ratio of pup/placenta weight) (C), placental weights (D), reabsorbed pups (resorptions) per litter (E) in WT and KO pregnant mice with and without leptin infusion. 2-Way ANOVA with Tukey’s posthoc test for multiple comparisons. N=6 WT+Vehicle and WT+Leptin, N=7 KO+Vehicle, N=4 KO+Leptin. *P<0.05.