The story behind C-sections in America: A state-by-state analysis and a new C-section predictor for pregnant women
Editor’s note: We’re not here to give medical advice about whether or not a C-section is right for you. We aim to help you get the information you need to talk to your gynecologist and make decisions with confidence.
Health care is personal, and pregnancy is particularly personal. If you’re pregnant, there are many things outside of your control—but there are also a lot of decisions you have to make along the way. One topic that’s on many expectant mothers’ minds is Cesarean sections (C-sections), and whether they’ll have to get one.
According to the Centers for Disease Control and Prevention (CDC), the national C-section rate was 32.2% in 2014. In April, the World Health Organization suggested that the target rate internationally should be half of that, between 10 and 15%, given the health risks associated with the procedure. The United States has set a goal of lowering its rate among low-risk women by 10% by 2020, according to the HealthyPeople.gov initiative, and it seems like there are almost daily articles in the news about C-section rates being too high and how hospitals and doctors are working to lower their rate.
Given how much information is out there about pregnancy and C-sections, our team was surprised to find that there isn’t an easy way for women to answer the question, “What’s my chance of getting a C-section?” It is also hard for women to find out how certain factors—like where they live or what conditions they have—might affect how they give birth.
So, we dug into our database and took a look at the factors that can lead to delivery via C-section, analyzing 4.4 million deliveries from 3.5 million distinct women in the United States over the last 5 years. We’ve identified differences across states, created an interactive map that lets you explore C-section rates by facility zip code, and developed a tool for pregnant women that will predict their chance of having a C-section based on key health factors that are possible to know before the delivery day.
Before we dive into our findings, here’s a quick snapshot of what we learned:
- Our data shows that the average C-section rate across the United States is 37.1%, which is slightly above other national averages (reported in past years or from more limited sample sizes). The average rate we found is in line with the documented upward trend of C-sections since 1996, when the rate was 21%.
- For women who had a C-section previously, the average rate of C-section was 90.6%, perhaps because some hospitals and doctors are reluctant to try a vaginal birth after a C-section.
- Where you live matters, even at a state level: Florida ranks the highest for C-sections, with an average rate of 42.8%. Wisconsin ranks the lowest for C-sections, with an average rate of 28.0%.
Where you live affects your chances of having a C-section
There’s a clear relationship between where you live and your likelihood of having a C-section. To see rates for your area by zip code, you can play around with our interactive map.
According to our data, the five states with the highest C-section rates are: Florida (42.8%), New Jersey (42.3%), Connecticut (41.1%), Kentucky (41.0%), and Maryland (40.9%).
The five states with the lowest C-section rates are: Wisconsin (20.8%), Utah (28.1%), Minnesota (29.6%), South Dakota (29.6%), and Hawaii (30.0%).
The regional variations in our findings are broadly consistent with other studies of C-section rates across the country. Consumer Reports completed a large study in May 2014 in which they looked at 1,500 hospitals across 22 states. They list three Florida hospitals and one New Jersey hospital among those with the highest C-section rates, as well as three Utah hospitals among those with the lowest rates.
Why do C-section rates vary by state?
There are many reasons why states might have drastically different C-section rates. Ethnicity, race, culture, and socioeconomic status all may correlate with a woman's chance of having a C-section, according to this University of California Press study around racial-ethnic and socioeconomic disparities for C-sections in the US. There are also staff practices at hospitals that may correlate with childbirth outcomes. For example, one recent study shows that 24-hour on-call obstetricians and availability of midwifery care may lead to a lower rate of C-sections.
It is interesting to note that, despite anecdotal evidence, there is not much research to support the claim that C-sections by maternal request have significantly affected the nationwide rate. One third-party report by The American College of Obstetricians and Gynecologists estimates that C-sections by choice (also called “elective” or “maternal request” C-sections) occur in only 2.5% of births.
How personal health factors affect your chance of C-section
In addition to geography, we focused on a few key personal health factors that are possible to know before your delivery day. First, we looked at age. Consistent with third-party research, our data shows that older mothers are more likely to have a C-section than younger mothers. You can see how the rate of C-section increases with age in the chart below.
Next, we looked at previous C-section rates and success rates for vaginal birth after C-section (VBAC). According to our data, there’s a 90.6% chance of having a C-section if you’ve had one previously. While the percentage of women who have a trial of vaginal birth after a C-section is small (0.9% of all deliveries in our database), approximately 78% of those vaginal births were successful. It is likely that this high rate of success is, at least in part, due to the fact that a doctor is only likely to recommend a vaginal delivery following a previous C-section if the patient is a good candidate.
Finally, we looked at a few other pre-delivery conditions that are known to affect pregnancy outcomes:
- multiples (twins, triplets, etc.)
- large or malpositioned baby
- bleeding during pregnancy
- excessive amniotic fluid
- diabetes (Type 1, Type 2, and gestational)
- high blood pressure
- Rh incompatibility
- smoking during pregnancy
Each of these factors contributes in a slightly different way to your overall chance of having a C-section. You can see the different C-section rates for each factor in the chart below.
This list isn’t exhaustive. In particular, there are some C-section risk factors that may emerge only on the day of delivery. These include emergency situations like failure to progress in labor or non-reassuring fetal status. We did not include these in the predictor tool because these are difficult for pregnant women or their doctors to anticipate. Regardless, since our sample size is very large, we had enough data on all of the aforementioned factors to build a C-section predictor that we feel is a useful indicator of your likelihood of C-section.
For more information about the data science behind our C-section predictor, read our methodology page.
Your chances of getting a C-section
To use our C-section predictor, you first answer a few simple questions about yourself and your pregnancy. We then calculate your predicted chance of a C-section based on the personal health factors you entered and using our data about 4.4 million deliveries over the last 5 years.
If you’re interested in seeing predicted C-section rates for doctors in your area, go to Amino’s find a doctor service and search for “pregnancy.”
A note for the holidays: how day of the week and Christmas Day affect C-section rates
With the holidays coming up, we wanted to understand how C-sections are coordinated by day of week, and even by days of the month. Our data shows that C-section rates vary based on the day of the week, with lower C-section rates occurring on weekends versus weekdays throughout the year. Christmas Day deliveries are also significantly less likely to be performed via C-section than deliveries on other days in December. We did not investigate the cause of this day-of-week or holiday effect, but we assume it reflects a combination of doctor, facility, and patient scheduling preferences for surgical procedures.
Make more confident decisions about your care
Amino’s mission is to empower people to make more confident decisions about their care, and our team is working on exciting new ways to give people trends and personalized predictions based on our database of 188 million Americans, 893,000 doctors, and 3.9 billion health care interactions. We created this predictor so that pregnant women can see their chances of having a C-section and use it to find the right doctor for their needs, or to use as a starting point for a conversation with their current doctor about what to expect.
Research and editing by Hannah Levy; interactive design by Sumul Shah; medical review by Jorge A. Caballero, MD.