The action of sex hormones could be altered through the introduction of exogenous synthetic substances, which have been shown by several studies to possess deleterious sequelae on the ovaries. Reports on the detailed histology following the exposure to Levonorgestrel (L) are scanty and none has espoused the use of progestin-only contraceptives (post-coital pills) on the ovary. The study, therefore, evaluated the histological sequelae following exposure to Levonorgestrel on the Wistar rat ovary. Ethical approval for the study was granted by the Research and Ethics Committee in the Faculty of Basic Medical Sciences of Delta State University, Abraka. Forty Adult female Wistar rats, grouped into A and B were investigated. A, control, consisting of 20 rats, and B, test group, 20 rats. Both groups were further divided into 10 subgroups respectively, with each consisting of 20 rats. Subgrouping was done accordingly into 3rd, 6th, 9th, 12th, 15th 18th, 21st 24th 27th and 30th days respectively. Group A received food and distilled water only while group B rats received 0.025mg kg-1 of (L), food and water. Ovary revealed untoward effects of Levonorgestrel, seen at day 6 to day 30 for routine staining pattern. Also seen is a gradatory staining intensity of brown nuclei for progesterone and estrogen receptors for immunochemical staining pattern. This treatise underscored the deleterious outcomes in female gonads exposed to Levonorgestrel and cytoarchitectural peculiarities in ovaries exposed to either combined or emergency oral contraceptives were well espoused. پرونده مقاله