A woman gave birth to a baby boy. Then a month later, her water broke again.

A 20-year-old woman from Bangladesh has given birth to twins just 26 days after giving birth to her son last month.

After being rushed to hospital feeling ill, Arifa Sultana discovered that she was not just unwell, but that her water had broken, and that she was giving birth to twins.

The newborns were delivered by c-section at Khulna Medical College Hospital, and the boy and girl were delivered safely and healthily with no complications, despite not being monitored throughout the pregnancy.

It was during an ultrasonography that doctors discovered the woman has a double uterus, a condition that left her second pregnancy unnoticed.

“It’s a rare incident. I have seen such a case for the first time. I had not even heard about such an incident before,” the chief of the hospital’s gynaecology department, Sheila Poddar, told local news site Tribune India. 

Experts have been left wondering how the extra heartbeats went unnoticed.

Uterus didelphys, a double uterus, is a rare condition and occurs in approximately one in 3000 women, according to gynaecologist and fertility expert Dr Sonya Jessup.

Dr Jessup told Mamamia it is an uncommon abnormality of the uterus and sometimes also the cervix and vagina.

“In a female foetus, the uterus develops when two mullerin ducts (two parallel tubes) fuse and the middle portion disappears to create a uterus. With this process women end up with one uterus, one cervix, one vagina and two ovaries.

“In some women this process fails to happen in the usual manner. There are many different variations of uterine abnormality ranging from a heart shaped uterus to a situation where a woman may have two uteri, two cervices, and a double vagina.”

Dr Jessup said uterus didelphys can be diagnosed by an ultrasound or speculum examination and often women will not recognise any abnormalities until they begin menstruation or become sexually active.

She said that in general, women with the condition are able to conceive spontaneously and usually the pregnancy will be in one uterine horn only.

There have been other cases of women carrying multiple children in both uteri – such as UK woman Hannah Kersey who gave birth to triplets in 2003.

Two of her babies were identical twins born from one uterus, and her third was born from the other in what was believed to be a world first.

The Mayo Clinic states uterus didelphys can create extra risks, such as miscarriage and premature birth, during pregnancy.

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