At midcycle, 2 weeks before or 2 weeks after a menses, the main physiologic event is ovulation. Most women are not aware of ovulation but some are on a regular basis. When noticeable pain happens at midcycle, physicians often attribute the pain to a small amount of bleeding that can occur from the site of egg ovulation. Usually this type of pain alternates from side to side in different months although it can present consistently on one side if ovulation seems to favor one ovary.
If one looks in the pelvis with a laparoscope in the 2nd half of the menstrual cycle in a woman who has severe PMS symptoms, the most common finding is a normal appearing pelvis. Sometimes there are large dilated pelvic veins almost to the point of being pelvic varicosities. There still is controversy among physicians as to whether pelvic varicose veins cause pain. This is also sometimes referred to as pelvic congestion syndrome.Newer studies using advanced imaging techniques of MRI, CAT scans and doppler ultrasound have rekindled treatment of these large veins to see if pelvic pain may respond. Embolization of the veins and even laparoscopic ligation have been used to treat this pain but as yet there have not been randomized trials.
There can also be cyclical pain presentations from non-gynecological causes such as: