A woman in Bangladesh gave birth to twins less than a month after giving birth to her first child. 

According to Dhaka gynecologist Dr. Sheila Poddar, 20-year-old Arifa Sultana gave birth to a son at that city's Ad-Din hospital in February. Shortly thereafter, she returned complaining of abdominal pain. 

When doctors performed an ultrasound, they discovered that Sultana was pregnant with twins. Sultana has a rare congenital abnormality called uterus didelphys, which causes her to have two separate wombs. As an ultrasound was not performed during her initial pregnancy, the twins were not discovered until after her son was born. 

"It is not very common to have two uteruses. When the uterus develops, it comes from two tubes and those tubes fuse together," Dr. S.N. Basu, head of gynecology at Max Healthcare hospital in New Delhi, told CNN.  "For some women, the fusion does not occur and the dividing wall does not dissolve."

Basu opined that folks from more rural areas may not "know how many children they are pregnant with and sometimes whether they are pregnant also."

Poddar reported that a C-section was performed and both twins —a boy and a girl—as well as their mother are perfectly healthy following the operation.

"All three children are safe and healthy," she said. "The mother is also fine."