Nutrition plays a pivotal role in the reproductive performance of ewes. Ewes in optimal body condition tend to have larger litters, higher lamb survival rates, and heavier lambs at weaning. While obese animals may suffer a reproductive insufficiency. Therefore, monitoring the body condition of ewes throughout their reproductive cycle is essential for maximizing flock productivity. The present work aimed to investigate the effect of rump fat depth of subtropical ewes (n = 62) at mating on their embryonic and fetal development. Pregnancy rates, reproductive wastages, level of leptin hormone, and embryonic and fetal measurements, were studied. Data were analyzed using one-way analysis of variance to determine statistically significant differences among backfat depth groups (≤1 mm; >1 - ≤ 1.5 mm; >1.5 - ≤ 2 mm; >2mm). The lowest rump fat depth group had the lowest values for pregnancy rate, ewes lambed and lambs born per ewes conceived and leptin concentrations; the highest reproductive wastage was attained. Higher fetal measurements (crown-rump length, the largest placentome diameter, biparietal diameter, chest depth and trunk diameter) were observed for ewes having a backfat depth of more than 1.5 mm. However, no significant differences were observed for ewes with backfat thicknesses of >1.5 to ≤2 mm and those having >2 mm regarding all the measured traits. Therefore, controlling the rump fat depth of ewes before mating is so important for enhancing the investment of sheep flocks by reducing feeding cost and to get higher proportion of born lambs with higher weights.