C-sections a critical factor in preterm birth increase

May 28, 2008

Cesarean sections account for nearly all of the increase in U.S. singleton preterm births, according to an analysis of nine years of national birth data.

Between 1996 and 2004 there was an increase of nearly 60,000 singleton preterm births and 92 percent of those infants were delivered by a cesarean section, (c-section), according to research by investigators from the March of Dimes and the U.S. Centers for Disease Control and Prevention (CDC) that will be published in the June issue of Clinics in Perinatology.

While singleton preterm births increased by about 10 percent during this time, the c-section rate for this group increased by 36 percent.

Preterm birth is a serious and costly health concern and is the leading cause of death in the first month of life. More than 520,000 babies – one out of every eight – are born too soon each year in the United States.

Late preterm babies, those born 34-36 weeks gestation, account for most of the increase in the US singleton preterm birth rate. These infants have a greater risk of breathing problems, feeding difficulties, temperature instability (hypothermia), jaundice, delayed brain development and death than babies born at term. This new analysis shows that that these late preterm infants had the largest increase in c-section deliveries.

“While maternal and fetal complications during pregnancy may result in the need for a c-section, we’re concerned that some early c-section deliveries may be occurring for non-medically indicated reasons,” said Alan R. Fleischman, M.D., the March of Dimes medical director and senior vice president. “We need research to determine how many c-sections that result in preterm babies are not medically indicated and may place both mother and baby at risk for little or no medical benefit. ”

C-sections are the most common major surgical procedure for women. More than 30 percent of the 4.1 million U.S. live births are delivered via c-section and the rate has increased dramatically since 1996. A c-section delivery can be lifesaving when there are complications during pregnancy, but it is a major operation with potential risks to the mother from the surgery and anesthesia and to the baby, if the delivery occurs too soon. The March of Dimes is concerned that some early deliveries may occur without good medical justification and may be done at the request of the mother or based on an inappropriate recommendation from the doctor.

Source: March of Dimes Foundation