Anatomic uterine defects are present in 15% of women who miscarry three or more consecutive times
Pregnancy loss can be physically and emotionally taxing for a woman, especially when faced with recurrent losses. Recurrent pregnancy loss (RPL), also referred to as recurrent miscarriage, is historically defined as three consecutive pregnancy losses prior to 20 weeks from the last menstrual period. About 15% of women with a history of recurrent pregnancy loss can trace these losses back to anatomic uterine defects.
Anatomic uterine abnormalities can be classified as congenital or acquired.
Congenital anatomic uterine abnormalities, or deformations of the uterus, are present at birth. A common condition is a uterine septum in which the uterine cavity is partitioned by a longitudinal septum or wall. Women with a uterine septum have about a 75% risk of pregnancy loss due to the anatomic structure of their uterus. Other fairly common congenital abnormalities may include a bicornuate uterus in which a woman has separate uterine cavities sharing a single cervix. Another is a unicornuate uterus, a congenital uterine abnormality that results in a small uterus with only one functioning fallopian tube.
Intrauterine adhesions and fibroids fall into the category of acquired anatomic uterine defects. These are not present at birth, but occur in a woman gradually over time. Intrauterine adhesions, also commonly referred to as Asherman’s Syndrome, form when scar tissue builds up between the inner walls of the uterus causing the walls to bind together. The most common cause of intrauterine adhesions is injury following a surgical procedure, such as a D&C, involving the cavity of the uterus. Adhesions can significantly impact the development of the placenta in the first few weeks of pregnancy and result in early pregnancy loss.
Uterine fibroids are generally benign tumors that form within the walls of the uterus and sometimes the cervix. About 20% of women of reproductive age will experience fibroids, but women of African descent have a higher incidence of fibroid formation, about 50-80%. Uterine fibroids can interfere with a pregnancy by affecting blood flow to the uterine cavity and decreasing the ability of an embryo to implant to the uterine wall or to develop.
Diagnosis of an anatomic uterine abnormality can be made by a fertility specialist.
Accurate diagnoses of anatomic uterine defects are usually made through ultrasound, office hysteroscopy, or through a hysterosalpingogram (HSG), an x-ray procedure used to determine the shape of the uterus. Hysteroscopic resection of intrauterine adhesions and intrauterine septa are indicated if these abnormalities are identified. Patients undergoing successful hysteroscopic septum resection seem to enjoy near normal pregnancy outcomes, with term delivery rates of approximately 75% and live birth rates approximating 85%.
If you have had three or more consecutive clinical pregnancy losses without a live birth, consult with our Louisiana fertility specialists to rule out any anatomic uterine abnormalities.