A normal pregnancy lasts nine months, in which the fetus grows and develops and body organs. Regular medical check-ups and prenatal tests are important to help both mother and baby to be healthy. It will also keep track of the baby's development to see if there are any abnormalities.

In some cases, doctors can help treat the problem before the baby is born. But even if they cannot, it can still be helpful for the future parents to know the problem in preparation for any challenges that may come.

According to the US National Institutes of Health, there are two main categories of birth defects: structural and functional or developmental birth effects. Structural birth defects include cleft lip or cleft palate, heart defects, abnormal limbs, and neural tube defects such as spina bifida. Meanwhile, functional birth defects are those problems in the nervous system or brain, sensory, metabolism, and degenerative disorders.

With so many birth defects to mention, it is rare to have a birth defect that has only been recorded for 35 times since it was discovered over a century ago. A growth of a second mouth is not usually on the cards.

An Extra Oral Cavity

During a regular prenatal check-up, a baby's scan in its third trimester showed an unusual mass to the right of the baby's mouth, ScienceAlert reported. However, ultrasonography did not allow health care experts to resolve the problem.

They first thought that it was a cyst, or maybe fibrous dysplasia in which one twin absorbs another during development. It was only when the girl was born that they were able to identify the unusual mass as a small second mouth with its own lip, cavity, teeth, and a tiny tongue that moved in synchrony with her main tongue as she fed.

Doctors from the medical university of South Carolina noted in their case report that the skin around the second mouth would occasionally develop a "raw surface" and would drain a clear fluid, which they believe was saliva.

Fortunately, the second mouth does not cause any problems with her breathing and ability to feed. It did not even connect to her central mouth.

This condition is an example of diprosopus or the duplication of head and/or facial structures. It is a very rare condition, with only 35 cases have been recorded in humans since 1900. Extreme cases can lead to full facial duplication, but when it only involves one area, it is usually the mouthparts that are involved.

Until today, doctors are baffled by this condition as it occurs more often in females than in males.

The doctors explained that "duplication of craniofacial structures typically occurs as part of a syndrome and is often associated with cleft lip and cleft palate, Klippel-Feil syndrome, and Pierre Robin sequence."

The baby's craniofacial duplication is a rare case that presented no associated syndromes or abnormalities, which allowed the doctors to perform a surgery to remove the extra mouth when the baby reached six months old.

Baby Undergoes Surgery to Remove the Second Mouth

The doctors were able to remove some muscle, bone, mouth mucous membrane and esophagus tissue, the salivary glands, and six unerupted teeth. They did this surgery while carefully trying to preserve her facial nerves.

The baby healed well and required no further treatment after her surgery. Although she has trouble relaxing the right part of her lower lip, probably due to some missing nerves, the doctors said.