CHICAGO (AP) — New research shows U.S. women are increasingly using donated eggs to get pregnant, with often good results.

What the researchers call the ideal outcome happens in only about 1 out of 4 pregnancies from donor eggs, but that's up from 19 percent a decade ago.

The ideal is a single baby born on time at a healthy weight. More than a third of donor egg babies are twins and many are born pre-term; both conditions increase risks for complications.

The study looked at data from 2000 to 2010. It's from researchers at Emory University and the federal Centers for Disease Control and Prevention, and was published online Thursday by the Journal of the American Medical Association.