There
has been a rise in the number of US women using donated eggs to get pregnant,
according to new research. 
The
research indicated that over half of these pregnancies (56pc) resulted in a
live birth in 2010, but 37 percent were twins and many were born prematurely,
at low birth weights.
The
study found attempts using donor eggs increased over the decade from 10,801 to
18,306. Transferring just one embryo, to avoid multiple births, also increased,
from less than 1 percent to 15 percent in 2010.
Lead
author Dr. Jennifer Kawwass of Emory University said researchers still need to
find better ways to identify which embryos have the best chance of resulting in
healthy babies.
Dr.
William Schlaff, ob-gyn chief at Thomas Jefferson University in Philadelphia,
said the rise in use of donor eggs “is probably partly a social story.
Women
not having success in becoming pregnant in their late 30s and 40s are more
comfortable using donor eggs” and techniques have improved to raise
success rates, Schlaff said. He was not involved in the research.
The
study, by researchers at Emory University and the federal Centers for Disease
Control and Prevention, was published online Thursday in the Journal of the
American Medical Association and presented at the American Society for
Reproductive Medicine’s annual meeting in Boston.
For
women who use in vitro fertilization and their own eggs, the live-birth rate
varies by age and is highest — about 40 percent — among women younger than 35.
Women
who use IVF with donor eggs are usually older and don’t have viable eggs of
their own. Because the donor eggs are from young, healthy women, they have a
good chance of success, generally regardless of the recipient’s age.
The
average age of women using donor eggs was 41 in 2010 and donors were aged 28 on
average; those didn’t change over 10 years.