Anatomical Consequences of Endocrine Disruption by Bisphenol A on Uterine Morphology and Endometrial Receptivity in Wistar Rats: A Translational Study for South West Nigeria

Bisphenol A is a synthetic oestrogen analogue present in food packaging, beverage containers, and dental materials, and has been detected in urine samples of urban Nigerian women at concentrations associated with endocrine disruption. Uterine morphology and endometrial receptivity are oestrogen-dependent processes central to implantation success, and dysregulation by bisphenol A may contribute to implantation failure, endometrial hyperplasia, and subfertility. This study aims to provide a comprehensive anatomical characterisation of bisphenol A-induced uterine morphological and molecular changes relevant to implantation in Wistar rats. Seventy-two adult female Wistar rats will be randomised to receive bisphenol A at doses of 5, 50, and 500 micrograms per kilogram body weight daily for 28 days. Uterine morphometric outcomes including uterine weight, endometrial thickness, glandular density, luminal epithelial height, and stromal vascularity will be quantified histologically. Immunohistochemical expression of oestrogen receptor alpha, progesterone receptor, leukaemia inhibitory factor, and MUC-1 will be evaluated as markers of implantation window receptivity. RNA sequencing of endometrial tissue will identify bisphenol A-driven transcriptomic changes. This multimodal characterisation of bisphenol A-induced uterine anatomical and molecular alterations will provide original translational evidence on endocrine disruption risk for reproductive health in South West Nigeria.

Keywords: Bisphenol A, uterine morphology, endometrial receptivity, endocrine disruption, implantation