Abstract Sirenomelia, also known as “mermaid syndrome” is a very rare congenital deformity in which the legs fuse together, causing them to have an appearance of a mermaid tail. Abnormalities of the kidneys, large intestines, and genitalia are most often associated with Sirenomelia (Dharmraj & Gaur, 2012). This rare condition is usually associated with severe oligohydramnios and the prognosis is extremely poor. We present a case for review in which the patient who was in the second trimester of her pregnancy came in for a fetal anatomy sonogram and it was discovered that the fetus had Sirenomelia. However, the patient was not aware of this until the beginning of the third trimester.
Keywords: Sirenomelia, oligohydramnios, mermaid syndrome…show more content… This congenital anomaly is found in approximately 1 in 100,000 live births. Sirenomelia is also known as “mermaid syndrome” because the lower extremities fuse together to resemble a mermaid tail. Taori et al mentions that Sirenomelia has been classified into three types and they are: Simpus Apus, Simpus Unipus, Simpus Dipus. These classifications are determined if the fetus has feet, lower leg bones, and upper leg bones. The first type is if the fetus has no feet, one tibia, and one femur then the fetus is classified to have Simpus Apus. Type two is if one foot is present with two femur, two fibula, and two tibia bones then the fetus is Simpus Unipus. Type three is Simpus Dipus, in which the fetus has two feet and two fused legs resulting in a “flipper” or mermaid tail like structure. This condition is described as being three times more common in males. It also has a slight increase in risk with maternal age of less than 20 years and older than 40 years old. 1, 3 According to Stanton et al, this syndrome was once thought to be a fatal condition; however, since 1989, there have been four reports of children surviving with Sirenomelia. There is not much mentioned about this condition in our textbook. According to Henningsen, Sirenomelia had been thought to be an extreme form of Caudal Regression Syndrome (CRS) but it is currently thought to be a separate
