The oviduct on the affected side is intact (this criterion, however, holds not true for a longer ongoing ovarian pregnancy).An ovarian pregnancy can be mistaken for a tubal pregnancy or a hemorrhagic ovarian cyst or corpus luteum prior to surgery. Sometimes, only the presence of trophoblastic tissue during the histologic examination of material of a bleeding ovarian cyst shows that an ovarian pregnancy was the cause of the bleeding. Management
Ovarian pregnancies are dangerous and prone to internal bleeding. Thus, when suspected, intervention is called for. Traditionally, an explorative laparotomy was performed, and once the ovarian pregnancy was identified, an oophorectomy or salpingo-oophorectomy was performed, including the removal of the pregnancy. Today, the surgery can often be performed via laparoscopy. The extent of surgery varies according to the amount of tissue destruction that has
occurred. Patients with an ovarian pregnancy have a good prognosis for future fertility and therefore conservative surgical management is advocated. Further, in attempts to preserve ovarian tissue, surgery may involve just the removal of the pregnancy with only a part of the ovary. This can be accomplished by an ovarian wedge resection.Ovarian pregnancies have been successfully treated with methotrexate since it was introduced in the management of ectopic pregnancy in 1988.An ovarian pregnancy can develop together with a normal intrauterine pregnancy; such a heterotopic pregnancy will call for expert management as not to endanger the intrauterine pregnancy. Epidemiology
Ovarian pregnancies are rare: the vast majority of ectopic pregnancies occur in the fallopian tube; only about 0.15-3% of ectopics occur in the ovary.
The incidence has been reported to be about 1:3,000 to 1:7,000 deliveries. History
In 1614 Mercier (also shown as Mercerus) described ovarian pregnancy for the first time, as a condition separate from a tubal pregnancy. Once the study of physiology emerged, Boehmer classified extra-uterine pregnancy into three classes: abdominal, ovarian, and tubal. There were many doubters that such a condition existed, particularly Mayer, who wrote an essay not only denying the existence of ovarian pregnancy, but demonstrating that recorded cases to that time were other conditions. Then Cohnstein proposed four criteria that would need to be present for ovarian pregnancy exist. His requirements were: 1) absence of the ovary on the side in which the alleged pregnancy was located; 2) connection of the uterus and sac via an ovarian ligament; 3) cylindrical tissue must line the layers of the sac with direct connection between the tunica albuginea and sac wall; and 4) evidence of the amniotic cavity connection to the ovarian follicle or corpus luteum. These were replaced by Otto Spiegelbergs criteria in 1878, which have been used into the 20th century with additions and modifications.Up to 1845, about 80 cases of ovarian pregnancy were proposed. With Mayers 1845 denial that ovarian pregnancy could exist, physicians began taking more care in their descriptions and analysis of cases. Though numerous cases were evaluated, some failed to provide microscopic evidence and others failed to show the necessary histological changes of pregnancy, or failed on one or more of the criteria.