Why have cesarean deliveries become so common and is it ok?

By Eva Martin, MD of Elm Tree Medical Inc.

In 2009, the cesarean delivery rate hit an all-time high: 32.9%. 1 in 3 babies in the United States were delivered by cesarean section. C-sections can save lives, but many experts believe this number is too high. What factors lead to so many cesarean sections. What can we do to get a handle on this run-away statistic?

Although the cesarean section rate has not increased since 2009, it has remained essentially the same at about 32%. The rate started rising in the late 1990’s, when it was 20.7% in 1996. That’s a 50% increase over 13 years! Are these new cesarean deliveries saving lives? The short answer is no- despite doing more cesarean sections, outcomes for moms and babies have not improved.

Why has the cesarean delivery rate increased over the past two decades? Researchers point to a variety of possible causes. Most cesarean deliveries are performed because the baby’s head is too large to fit through the mother’s pelvis or because labor stops progressing (the cervical dilation stops changing). You may be wondering if babies are bigger now. Yes, birth weight is in fact increasing. Maternal weight is also increasing. More pregnant women are obese now, and women gain more weight during pregnancy.

Furthermore, more women are asking for cesarean sections even if they do not have a medical reason to need one. In the US, this number could be as high as 4% of cesarean sections. This number is even higher is certain countries, like Brazil, Taiwan, and Chile. Finally, some research points to medico-legal concerns. OBGYNs who are afraid of being sued may be more likely to perform a cesarean delivery.

How can we staunch the tide of cesarean deliveries? The first way is by supporting “Trial of Labor After Cesarean” or TOLAC. Historically, doctors believed in the adage, “once a cesarean, always a cesarean.” In other words, doctors thought that once a woman had a cesarean section, vaginal delivery was not safe for future deliveries. We have since learned that many women who have a history of a cesarean birth can safely try for a vaginal delivery in a later pregnancy. However, the rate of vaginal birth after cesarean is still relatively low, about 10%.

The second way we can change the cesarean section rate is by altering the way doctors manage labor. The majority of cesarean sections are performed because either cervical dilation stops changing or the baby stops descending during the pushing phase of labor. Originally, doctors would perform a cesarean section if the dilation stopped changing for two hours. New recommendations guide doctors to wait at least four hours if contractions are strong enough and six hours if not. This extra wait time allows 60% of women to go on to deliver vaginally without any added harms. For those familiar with Elm Tree Medical’s work, this is one area we are diligently trying to improve by developing a tool to increase the accuracy of the very measurements that lead to all these cesarean sections! Currently, cervical dilation measurements are only about 50% accurate. Similarly, the amount of time doctors should allow for the pushing stage of labor has recently enjoyed a deluge of new data, encouraging longer pushing times. Instead of the old two-hour rule, doctors can now wait three hours for a first-time mom with an additional two hours if she has an epidural before recommending a cesarean delivery.

Many cesarean deliveries are performed because of concern for the baby’s heart rate tracing. 90% of heart rate tracings fall into a confusing category known as “Category 2” during the pushing phase of labor. Category 1 is definitely safe, and Category 3 is definitely not safe, but Category 2 is no-man’s-land in many cases. It has both concerning and reassuring features. Further research is needed to distinguish which Category 2 tracings should lead to cesarean deliveries and which are ok to continue labor.

Finally, the baby’s position can lead to a cesarean delivery. 4% of US babies are breech or feet first. If the baby is breech, most OBGYNs in the US now recommend cesarean delivery. However, a procedure called external cephalic version can sometimes turn the baby right-ways-down and prevent a surgery! It is a safe procedure in the correct setting and definitely worth a try. Furthermore, when babies are facing up instead of down during labor (sunny side up), they are harder to deliver. Rotating the baby’s head to the right position can lead to a higher chance for a vaginal delivery.

By raising awareness of the importance of minimizing cesarean deliveries and the ways we can do so, hopefully we will find a better balance between performing surgeries and saving lives and preventing complications.