The reasons as to why a rising number of women are delivering their babies by cesarean section have been revealed by US researchers.
Yale School of Medicine researchers found that while half of the increase was attributable to a rise in repeat cesarean delivery in women with a prior cesarean birth, an equal proportion was due to a rise in first time cesarean delivery.
Among these deliveries, factors such as slowly progressing labor and fetal heart rate concerns were the largest contributors.
Yale researcher Jessica Illuzzi, M.D., of the Department of Obstetrics, Gynecology and Reproductive Sciences and her co-authors analyzed indications for cesarean delivery on prospectively collected data from over 30,000 births at Yale-New Haven Hospital from 2003 to 2009.
"We found that more objective reasons, such as the baby being in a breech position and placenta previa, remained stable over time, while less objective reasons, such as slow progress in labor and concerns about fetal heart tracings contributed large proportions (>50 percent) to the increasing primary cesarean delivery rate," said Illuzzi.
In addition, suspected large infants, twin pregnancies, and preeclampsia contributed to the increase despite relatively stable rates of these conditions in the population during the seven-year study.
"This suggests that the use of cesarean for these indications is increasing," said Illuzzi.
The study will be published in Obstetrics and Gynecology.