More and More Babies Born Too Soon
Dramatic Increase in Preterm Births continued...
Twin birth rates rose by 52% and high-order births (triplets or
more) rose by an astounding 404% between 1980 and 1997, according to figures
from the National Center for Health Statistics. There were only about 1,000
high-order births in the U.S. each year prior to the introduction of assisted
reproduction. Today, there are between 6,000 and 7,000.
"Assisted reproduction, as it has been practiced, carries a
high risk of multiple births. With multiple births you can be absolutely
certain of having more preterm deliveries," says epidemiologist David A.
Savitz, PhD. "Studies have suggested that at least a third of the total
increase in preterm births can be attributed to multiple gestations."
Thanks to advances in diagnostic testing, obstetricians are
also better able to monitor fetal and maternal distress than they have been in
the past. As a result, inducing labor between 35 and 37 weeks gestation is far
more common than it once was. The practice is somewhat controversial, and some
argue that is being done too often.
"The willingness of clinicians to deliver early is probably
greater now than it has ever been," Savitz says. "I don't think they
perceive any problem whatsoever at delivering a baby at 35 or 36 weeks. But
when you look at large population studies, these babies do have a slightly
increased risk of [death] and certain developmental problems."
Charles J. Lockwood, MD, who leads the American College of
Obstetricians and Gynecologists' committee on obstetrical practice, has a
different view. Induction prior to 37 weeks is virtually never done without
good reason, he says.
"Early inductions have certainly increased, but the reasons
behind them more than justify the reasons for doing them," Lockwood tells
WebMD. "Fetuses in distress are more likely to die and have long-term
problems, so there are very good reasons for delivering them between 35 and 37
Early Delivery: 'A Problem We Should Have Solved'
While the rise in preterm deliveries may be explainable,
doctors have had less success preventing naturally occurring early births. It
is widely believed that stress and infections play a major role -- accounting
for roughly 70% of premature deliveries, Lockwood says -- but ob-gyns have not
yet figured out how to treat these labor triggers. Trials using antibiotics to
treat infections in pregnant women have so far been disappointing.