Longer Gestation Safer Even in Term Pregnancies
OB/GYN articlesBy David Douglas
NEW YORK (Reuters Health) May 31 - Babies born at term, but in the "early-normal" range, have higher neonatal, post-neonatal, and infant mortality rates, according to a new study.
," coauthor Dr. Marian Willinger told Reuters Health by email. "Babies born at early term gestations (37 and 38 weeks) are higher risk of dying in the first year of life than infants delivering full term (39 to 41 weeks). If a pregnancy is uncomplicated, babies should not be delivered before 39 weeks."
That advice is based at least in part on a new analysis by Dr. Willinger, from the National Institutes of Health, Bethesda, Maryland, and colleagues using U.S. data on more than 46 million singleton live births between 1995-2006.
Mortality rates fell for early-term and full-term births over this period. The greatest decline was in Hispanics (35.4%) followed by whites (22.4%), the researchers report in the June issue of Obstetrics and Gynecology.
Blacks had the smallest decline (6.8%), a finding that was largely due to the fact that neonatal mortality at 37 weeks of gestation did not improve. In fact, it increased nonsignificantly by 15.8%.
Overall, comparison of mortality at 37 vs 40 weeks showed a relatively higher risk with the shorter gestation both for whites and Hispanics (RR 2.6) and for blacks (RR 2.9). Risks at 38 weeks were also increased.
Compared to whites, Hispanics had a lower post-neonatal mortality rate (relative risk, 0.8) and blacks had a higher rate (relative risk, 1.8).
"While overall the rates of death in the first month of life for infants born at term gestations have declined over the past decade, there has been no decline in deaths in first month of life for babies born to black women at 37 weeks," Dr. Willinger said.
She and her colleagues conclude that this "unacceptable disparity... must be targeted by intervention to decrease the mortality rate for this high-risk group."
SOURCE:
Obstet Gynecol 2011.