A double uterus, also known as a didelphys uterus, is a rare condition in which a woman has duplication of the uterus. Although the exact reason why this congenital abnormality develops is unknown, it represents a lack of fusion of early embryonic structures. Symptoms can include infertility, pain with sexual intercourse, and abnormal menstrual bleeding. Treatment options for the condition can include various reconstructive surgeries to create a more functional reproductive tract.
All women with a double uterus have two uterine cavities. The extent of duplication seen in different women, however, can vary. Some women with this condition have two uterine cavities that join into a single cervix. Other women have two copies of the cervix, the vagina, the bladder, and the vulva along with the two uteri.
Although the exact cause is unknown, the developmental basis for having this condition is well understood. In normal female embryos, the reproductive tract is made from structures called the Müllerian ducts, which derive from early precursors of the kidneys. Normally, these ducts grow and eventually fuse to form one uterus connected to two fallopian tubes and two ovaries. Sometimes this process of joining the tubes together is unsuccessful, and without the fusion of the Müllerian ducts, two uteri form.
The symptoms caused by having a double uterus can vary by patient. Some patients have obvious manifestations of the condition, as they have two vaginal cavities. Patients that have only uterine duplication might not be affected by manifestations of the condition until later in their lives. They might report symptoms such as pain during sexual intercourse, abnormal menstrual cycles, infertility, or premature labor.
Making the diagnosis is most often done with imaging studies. Radiographic tests such as computed tomography (CT) scans and magnetic resonance imaging (MRI) tests can illustrate the presence of two uteri. A procedure called a hysterosalpingography takes a picture of the female reproductive tract after a dye is injected into the cervical canal. The benefit of this test is that it clearly outlines the walls of the uterus, and can distinguish a double uterus from other congenital uterine abnormalities.
Depending on the patient's symptoms and desires, the treatment for having a double uterus varies. Often the condition limits a woman’s reproductive capabilities, either by making sexual intercourse infeasible or by increasing the risks of premature or complicated delivery. Metroplasty, or plastic surgery of the uterus, reshapes the uterus to increase its reproductive capabilities and decrease symptoms associated with abnormal menstruation. Many women with the condition who do become pregnant opt for an elective Caesarian section to avoid experiencing problems with the childbirth process.