Imagine being pregnant and discovering that you have not one but two wombs (or uteri) and each of those wombs contains a baby. Such was the case of Andrea Barbosa of Clearwater, Florida. On September 15th, she delivered a baby boy and girl who had developed in two separate wombs. Thankfully, mother and both children are doing well.

Although twins are fairly common and represent 1 in 32 births, the type of twin pregnancy that Barbosa had occurs only 1 in 5 million chances in a condition called uterine didelphys or a double uterus.

Uterine didelphys falls under the category of Mullerian disorders and occurs in approximately 1 in 2,000 women. It is the result of a failure of the early female reproductive system (aka Mullerian ducts) to fuse between 9 to 11 weeks after fertilization. Mullerian disorders are usually undetected until a woman becomes pregnant, has pelvic pain when they begin to menstruate or has difficulty becoming pregnant. Although Barbosa had 2 separate wombs, some women have one but it  is divided by a membrane called a septum. This condition is known as a Septate uterus and is associated with an increased risk of miscarriages. Other forms of Mullerian disorders include a heart-shaped uterus (aka bicornuate) or the absence of a vagina. The cause of these disorders is unknown because affected women have normal female genes. Sometimes problems such as pelvic pain, menstrual problems including delayed period and painful intercourse are the first clues of this disorder. Other women may experience difficulty becoming pregnant, repeated miscarriages or have an ectopic pregnancy.

Mullerian disorders can also affect the outcome of a pregnancy because it is associated with frequent miscarriages in the first and second trimesters, poor growth of the fetus (aka fetal growth restriction), prematurity, or a ruptured uterus. Pregnant women with Mullerian disorders should have at least one consult with a maternal fetal medicine specialist to minimize adverse complications. Barbosa’s successful twin pregnancy and delivery with a double uterus is nothing short of a miracle and keeps the medical community humble. We wish the Barbosa family well.

Remember, a healthy pregnancy doesn’t just happen. It takes a smart mother who knows what to do.