The typical first-time mother takes 6 1/2 hours to give birth these days. Her counterpart 50 years ago labored for barely four hours.
That's the striking conclusion of a new federal study that compared nearly 140,000 births from two time periods.
One big implication: Today's obstetricians may be rushing to do cesarean sections too soon because they're using an out-of-date yardstick for how long a "normal" labor should take.
"That's absolutely correct," says Dr. Ware Branch of Intermountain Healthcare in Salt Lake City, a study author. Lead author Dr. Katherine Laughon of the National Institute of Child Health and Human Development agrees.
The past definitions of 'normal' labor have been used to draw the line as to when it's time to intervene with a cesarean delivery," Branch said during a telephone conference with reporters. "But what we've shown is that labor is actually longer ... than it was 50 years ago. That certainly calls for a reassessment of when one should draw the line for cesarean delivery."