Oestrogen deficiency after tubal ligation

4 of 7 women who had undergone tubal ligation within the past seven years were found to have oestrogen excretion concentrations at ovulation below the tenth percentile. A disturbance in the oestrogen/progesterone ratio as a consequence of localised hypertension at the ovary, when the utero-ovarian arterial loop is occluded at tubal ligation, is proposed as a possible cause of oestrogen deficiency syndrome, dysfunctional uterine bleeding, and menorrhagia after tubal ligation. Similar pathophysiology may occur after hysterectomy with ovarian conservation.