The Evolution of the Ageing Ovary

Abstract

This review updates the three-dimensional (3-D) microanatomic evolution of the ageing human ovary in a novel dynamic fashion, taking advantage of integrated scanning, transmission, corrosion casts and correlated techniques developed by ourselves. Tissues were collected from ovaries of women (aged between 28 and 70 years) during open surgery or endoscopic procedures. Our findings are as follows: the volume of the postmenopausal ovary was about one half of that present during reproductive years; postmenopausally the ovary became progressively atrophic and fibrotic. Particularly it showed a decrease of papillae and crypts which made its surface smoother than that of premenopausal tissue. In perimenopausal women (aged 45–55 years) the superficial cells covering the ovary were irregularly polyhedral and flattened. Their cytoplasm showed few organelles and in some instances apoptotic and/or necrotic cells. These features increased in most aged ovaries. Consequently the zones of the ovarian cortex (tunica albugina) could occasionally appear as consisting of dense fibrous collagen structures. Here only a few altered and swollen small follicles could be found. In the medullary regions variously sized cysts, some of which were blood filled (corpora atretica and hemorragica), were present along with retracted scars (corpora albicantia). In older women (aged 55–70 years) follicles were never observed. Instead, areas of thick density of collagen fibres and numerous sized scars (corpora albicantia) were present. A drastic reduction of the ovarian vasculature along with thickened vessel walls was commonly found. These typical features were already noted in perimenopausal women, but to a lesser extent. The detailed fine cell alterations of the ovary would appear to reflect the progressive decline in steroid hormone production as the ovary ages.