Women undergoing a hysterectomy without oophorectomy in their premenopausal years would expect to benefit from continued secretion of oestrogens to protect them from the conditions and symptoms associated with the climacteric and postmenopause. However, there is conflicting evidence regarding the effect of premenopausal hysterectomy on ovarian function. Some research indicates an increase in incidence and severity of menopausal symptoms following removal of the uterus, despite the ovaries remaining in place; others have failed to find evidence of a decrease in ovarian endocrine secretion, implying that the ovaries are unaffected. This article reviews the conflicting evidence regarding the effect of hysterectomy on ovarian function as well as examining evidence for counter-current exchange between the ovarian and uterine blood supplies. An hypothesis is put forward to explain how removal of a woman's uterus may affect her ovarian function.