Uterine Causes of Infertility can be Treated to Restore Fertility
The uterus must provide a welcoming home for the embryo, allow for implantation, and then adapt to the changes of the fetus. Any pathologic alteration in the uterine lining (endometrium) can decrease fertility or be a cause for miscarriage. Some women with such problems will experience vaginal spotting at irregular times during her cycle while others are without symptoms. Women with a prior history of uterine surgery will be at increased risk for uterine scar tissue.
A woman can be born with an abnormal shape of her uterine cavity (congenital uterine anomaly). An arcuate uterus has a small indentation at the top of the uterine cavity but it has no effect on fertility or risk of miscarriage. Other types of uterine anomalies have no effect on fertility but they do increase the risk of breech presentation at delivery and preterm labor. These include uterine didelphys (double uterus), unicornuate uterus (single-horn uterus), and bicornuate uterus (heart-shaped uterus). A septate uterus has an intervening wall of fibrous tissue between the two halves of the uterus which greatly increases the risk of miscarriage. This is the only congenital uterine anomaly where surgical correction is recommended immediately.
Uterine Tumors & Polyps
Myomas (or fibroids) are benign fibrous tumors that develop within the walls of the uterus. They can press into the uterine cavity and disrupt the endometrium. Therefore, depending on their location and size, they can increase the risk for infertility and miscarriage. Polyps are also benign tumors that can grow within the uterine cavity. They are typically softer and are more associated with sub-fertility.
Uterine surgery, such as C-sections or myomectomies, can lead to scarring within the uterine cavity which decreases the functional surface area for an embryo to implant. Evaluation of the uterus is typically initiated with a trans vaginal sonogram (TVS). This is the best method for diagnosing uterine myomas.
A sonohystogram is a test in which sterile saline is infused into the uterine cavity during the TVS. This test is ideal for outlining polyps or submucosal myomas (myomas inside the uterine cavity).
A hysterosalpingogram (HSG) is a radiological test in which dye (that can be seen by X-ray) is first infused into the uterine cavity and then into the fallopian tubes. Along with diagnosing polyps and myomas, it can demonstrate if a congenital uterine anomaly is present. Office hysteroscopy is an office procedure in which a camera (with a light and water source) is placed past the cervix and into the uterine cavity for a direct visual inspection. Treatment for uterine pathology typically involves surgery. Myomas that are 5cm in diameter or greater should be removed. Submucosal myomas, because they are in direct contact with the endometrium, should also be removed. Some surgeries may be approached solely through the cervix (hysteroscopic surgery), while others are approached through the abdomen. Abdominal approaches include via a laparoscope (small incisions) or via laparotomy (larger incision).