The long-term programming effects of neonatal hypermelatonemia on adult ovarian weight and
functions and serum hormone profiles have been studies in the Charles Foster strain of rats. The
neonates were administered melatonin (MT) i.p. (40 μg/animal/day) in the evening from day 0 to
day 21 post partum. The serum titres of T3, T4, estradiol and progesterone and, ovarian weight
and histoarchitecture were assessed on post partum days 22, 45 and 90. Though there was no
difference in adult ovary weight between control and MT programmed rats, there was increased
density of follicles with significantly higher number of antral follicles and corpora lutea in MT
rats. The number of atretic follicles showed a significant decrement. In conclusion, the present
observations reveal increased progesterone but decreased estrogen level and increased
protection against follicular apoptosis in the adult due to neonatal melatonin programming
thereby increasing follicular number and corpora lutea.
