Dec. 5, 2013— -- A Sacramento couple hit the genetic lottery when they welcomed identical triplets, conceived without fertility drugs, last month.
Doctors say the odds of naturally conceiving identical triplets, where a single fertilized egg is divided into three separate embryos, may be as high as "one in a million"
The parents of the triplets told reporters they were happy about their three bundles of joy.
"It's everything at once. I think you can get lost just staring in their faces," said the triplets' mother, Hannah Hepner. "But it's overwhelming to think about everything to come."
The newborn babies each weighed in between three and four pounds at birth.
Dr. William Gilbert, the director of Women's Services for Sutter Health in Sacramento, Calif., treated the Hepner family and said there was not a definite rate for the number of identical triplets born every year.
"It's hard to calculate a conservative estimate," Gilbert told ABCNews.com about the rate of naturally conceived identical triplets. "One in 70,000 that would be on the low end, the high end is one in a million."
While the Hepner babies were born healthy, carrying identical multiple fetuses during pregnancy can mean extra complications, said Gilbert.
Unlike fraternal twins, identical twins often share the placenta and are at the risk of twin-to-twin transfusion syndrome. The condition, where blood from one fetus transfers to another, can affect the growth of the triplets during the pregnancy.
"The blood vessels that come from the umbilical cord can mean too much blood flow to one fetus and not enough to another," said Gilbert. "I worry more about the identical twins more than fraternal twins."
Gilbert said one complication for the Hepner family was that Hanna Hepner suffered from preeclampsia prior to giving birth. The condition is characterized by a sudden rise in blood pressure after the 20th week of pregnancy.
Gilbert explained preeclampsia is caused by the placenta. With triplets, there were three times the amount of placenta that could potentially cause complications.
"Mom starts getting high blood pressure and it gets so high she could have a stroke," said Gilbert of preeclampsia. "It's a delicate balancing act, keeping the babies inside as long as it's safe for them."
Gilbert said most triplets are delivered at 32 weeks into the pregnancy and the Hepner babies were delivered healthy at 33 weeks.