C-section not tied to subsequent stillbirth

NEW YORK (Reuters Health) - Contrary to recent findings, there appears to be no increased risk of unexplained stillbirth (fetal death) late in second pregnancies following caesarean section in the first pregnancy, Canadian researchers report.

"Our study," study chief Dr. Stephen L. Wood told Reuters Health, "did not confirm the previously described association between cesarean section and subsequent stillbirth. As there have been other studies with similar results to ours, we do not think that cesarean section is likely a true cause of stillbirth."

The rates of stillbirth continue to rise in North America and a possible association with prior cesarean section, as suggested in a recent study of Scottish women, "is of significant concern," Wood of the University of Calgary, Alberta, and colleagues note.

To investigate further, they took a look back at data on more than 150,000 second births that had taken place in their province.

The team found that the rate of stillbirth occurring shortly before delivery, also known as the antepartum period, was 3.0 per 1000 in the previous cesarean section group versus 2.7 per 1000 in those with previous vaginal delivery. The difference was not significant.

This continued to be so even after a variety of adjustments and allowance for factors such as smoking during pregnancy, maternal age, and a previous stillbirth.

In light of these findings, the researchers advise that "it would be very premature to conclude a causal association exists."

"However," they add, "given the important potential public health implications, further research on this question should be undertaken."

SOURCE: BJOG: An International Journal of Obstetrics and Gynaecology, May 2008.