News Plus慢速英语:美国42岁妇女自然受孕产下三胞胎 实属罕见

You're listening to NEWS Plus Special English. I'm Mark Griffiths in Beijing.
A Southern California woman has given birth to identical triplets, instantly doubling the size of her family.
April Dooley's three sons were born in roughly 4-minute intervals on Jan. 13. She named them Patrick, Owen and Liam.
42-year-old Dooley says she burst into tears when she looked at her first ultrasound and learned she was carrying a trio-to-be.
She and her husband, Brad, wanted their 5-year-old daughter Kaitlyn to have a companion at their home in Long Beach. They weren't expecting their family to grow so precipitously.

All three boys are healthy, although Liam required surgery for an intestinal problem. The surgery went well.
The triplets arrived six weeks early, which is common with multiple births.
With infertility treatments and other assisted reproductive technologies, the number of multiple births has grown greatly since the 1980s in the U.S.
However, the occurrence of naturally conceived identical triplets is extremely rare. Identical siblings are produced when an egg is divided in utero. Fraternal siblings and those from artificial treatments come from different eggs.
The Dooleys didn't use fertility treatments.
Despite the rarity, it's the second known set of identical triplets born in California in several months.