Melatonin, synthesized in the pineal gland, participates in the regulation of physiological processes during gestation and fetal development. However, the effects of its reduction on intrauterine life are not yet fully understood. The objective of this study was to evaluate the perinatal development of the offspring of rats undergoing pinealectomy. The protocol was approved by CEUA/UFS (No. 4723240225). Forty-five-day-old Wistar rats were divided into two groups: Sham (SHAM, n=3; 29 pups) and Pinealectomized (PIN, n=4; 37 pups). At three months of age, after surgery, estrous cycle and mating were monitored. The offspring were monitored daily from postnatal day (PND) 2 to 40, with systematic recording of physical development milestones: eye opening, ear opening and vaginal canal development, ear development, incisor eruption, lanugo and hair development, and testicular descent. Offspring of PIN mothers showed delayed eye opening, ear opening development, ear development, incisor eruption, and lanugo development compared to the SHAM group. There was no statistical difference in hair development or genital development. It is concluded that removal of the gland causes delays in the perinatal physical development of the offspring, suggesting a relevant role for melatonin in this process, which may compromise early somatic maturation, possibly due to the loss of its antioxidant and circadian rhythm regulating effects. Keywords: Melatonin, neurodevelopment, pinealectomy.