This post is not about the indications for a c-section nor about the ever increasing number of c-sections. This post is about the actual risks of a c-section, which I find glossed over by some and exaggerated by others.
A great study was published last year by researchers in Finland (Pallasmaa et al. Acta Obstetricia et Gynecologica 2010). They prospectively looked at the complication rate among almost 2,500 women having a c-section during a 6 month time frame. It’s a well done study and it provides good solid data.
The c-section rate was 16.6% and ranged from 12.4% to 24.1%, so in some hospitals the c-section rate is on par with the US, an interesting aside. The most common reason for a c-section was failure of labor to progress (28.6%) and the second most common was fetal distress (21.7%). Again, fairly similar to our population.
While many different complications were recorded, serious complications were defined as the following: more than 1,500 ml of blood loss, need for blood transfusion, hysterectomy, needing another surgery, septicemia (a serious infection), blood clots, pulmonary edema, and pneumonia.
The rate of serious complications for all c-sections was 10.4%. When the groups were stratified, women who were having an elective c-section had the lowest rate of serious complications: 7.1%. As expected emergency c-sections and crash c-sections (ultra emergent) had far higher serious complications rates: 11.7% and 25% respectively.
Elective c-sections by far have the lowest complication rates, because membranes are typically not ruptured lowering the infection risk. Also, some of the serious problems that lead to an emergency c-section, such as severe bleeding or fetal distress related to infection, will by their very nature increase the risk of surgical complications.
Other factors that increased the complication rate in the study were obesity (BMI > 30), pre-eclampsia, and prematurity. Obesity makes surgery more challenging, increasing blood loss and the infection rate. Obese women are 50% more likely to have a c-section complication compared to those women who are not. Pre-eclampsia increased the complication rate by 60%, which makes sense because these women have vascular problems. Being less than 30 weeks pregnant doubled the risk of serious complications. In fact, complications were highest for women with pre-eclampsia and prematurity less than 30 weeks. Many premature deliveries are related to infection, so this association also makes sense. Operating on uterus that is infected is far more likely to result in bleeding, blood clots, or a serious infection after the procedure is over.
So c-sections are not benign. Overall, 27% of all c-sections will have some kind of complication and 10.4% of women will have a serious complication. An elective c-section (typically meaning a healthy mom in a controlled situation) has the lowest risk of complications, but that risk is still 7.1%. That is higher than a vaginal delivery.
This information is important when counseling women about c-sections as well as part of our discussion about the high c-section rate. If you have an infection or an abruption as an indication for your c-section, the serious complication rate of 11.7% for an emergency c-section may actually be low, because the outcome for both you and your baby could be much worse without intervention. However, for the woman requesting a c-section because she is afraid of labor, discussing these complications is important part of discussing the real risks of both vaginal delivery and c-section.
I had an indicated c-section for chorioamnionitis at 26 weeks. Less than 24 hours later I was septic. If I had waited and done a trial of labor, my boys would most likely have done far worse as the infection in my blood stream would have reached them. For me, the risk of a serious complication was a fair trade off (if I had been in that study, I would have been in the serious complication rate as I was septic post delivery). But to do everything for my boys was my only option. When a c-section is needed, it is needed.
The c-section conversation is emotionally charged for many, many reasons. And all are valid. However, these kinds of studies help us really know what we are talking about when we are discussing risk, and are invaluable in counseling patients as well as an important contributor in the discussion about our c-section rate in the United States.