Peripheral Melatonin Concentration and its Correlation with Estradiol and Progesterone Levels during Different Months of Pregnancy and after Delivery in Women

There is lack of basic information about peripheral melatonin level and its relationship with gestational hormones i.e., estrogens and progesterone, in human females. The present study addressed this issue and aimed to find the relationship between the levels of melatonin and estrogen and progesterone during different weeks of gestation, during parturition and during post-partum. The data suggest that there is a definite ratio of melatonin with both the steroids hormons before and during gestation as well as post-partum. An inverse relationship between the levels of estrogen and melatonin was observed in non-pregnant and post-partum women, while a direct relationship was observed during gestation. These two different types of hormonal relationships might be essential for maintenance of pregnancy. The inverse relationship of melatonin with progesterone during parturition may serve as a signal for parturition.