Woman Becomes Pregnant Twice in 10 Days Due to Insanely Rare Medical Phenomenon

After struggling to conceive, Kate and Peter Hill were overwhelmed with emotion when they found out they were pregnant, but had no idea they were going to get pregnant again 10 days later. In 2006, Kate was diagnosed with polycystic ovarian syndrome, which is a condition that prevented her from ovulating. Following the difficult news, Kate underwent hormone treatment and was surprised with a miracle baby. Ten days later, they found out they had gotten pregnant again!

"Superfetation" is an incredibly rare medical phenomenon in which a woman becomes pregnant while already expecting — there are only 10 documented cases of this in the entire world. "I had fallen pregnant and my body had spontaneously released another egg, giving the embryos different gestational ages," Kate told Today Tonight.

Although most women do not ovulate once they become pregnant, Kate did. Her baby girls, Charlotte and Olivia, were given two different due dates: Dec. 20, 2015 and Dec. 30, 2015. They were born together two days before the scheduled C-section and measured very differently in size and weight. The 10-month-old baby girls even have different blood types.

This miracle pregnancy story is so rare that the couple's obstetrician didn't know what to do because he had never seen anything like it before. "Superfetation is so rare that I could not find any literature in the medical review websites at all," Dr. Brad Armstrong said.

"What makes this case even more rare," Kate explained, "is that my husband and I only had intercourse one time. His sperm stayed alive for 10 days to fertilize the second egg released." Peter's response? "Hole in one, maybe."