The left ovarian vein is located in the abdominal and pelvic area and drains blood from the left ovary. The vein is found in the ligament that holds the ovary in place at the end of the fallopian tube, called the suspensory ligament of the ovary. The fallopian tubes are the tubes through which eggs travel in order to get from the ovaries to the uterus.
At the top of the ovary is a bundle of vessels known as the pampiniform plexus, which is where the vein begins. It ends at the left renal vein, where blood travels from the kidney to the right atrium of the heart via the inferior vena cava for a fresh supply of oxygen.
Ovarian veins, also called gonadal veins, change as a woman matures. Blood flow to the ovaries increases in order to facilitate the release of an egg into the fallopian tube. During pregnancy, the ovaries stop working because a fetus is growing, so the veins reduce blood flow accordingly. In menopause, when eggs are no longer viable, blood flow again slows and stops.
Blood clots within the left ovarian vein occasionally occur. Surgery used to be considered the best option, but now many OB/GYNs prefer the use of blood thinners to reduce the clot.