Approximately 11 percent of pregnant women have uterine fibroids. And while these benign growths may pose no trouble at all, clinical literature suggests they may be responsible for a 27 percent increased risk of delivering cesarean section.
A paper published in the Annals of Epidemiology1 further investigated this link. Between December 2000 and June 2010, Velez Edwards of the Department of Obstetrics and Gynecology at Vanderbilt University Medical Center in Nashville, Tenn., and a team of researchers enrolled 2,635 African American and Caucasian pregnant women in the Right from the Start study.
Through first trimester ultrasounds, the team verified the presence of fibroids along with number, type, and size. Interviews were performed and medical records collected to gather information such as reproductive history and route of delivery.
Results showed that 11.2 percent of the women enrolled had fibroids and 29.8 percent gave birth through cesarean section. These numbers indicated that women with fibroids had a 27 percent increased risk of delivering cesarean section in comparison to women who were fibroid-free.
The authors also found that this risk was heightened in women with fibroids larger than 3 centimeters in diameter and women with the largest total fibroid volumes. Although this study supports the link between larger fibroids and cesarean delivery, other studies have disputed the association.
Along with size, fibroid location and type may also present a risk.
“Fibroids can, depending on their location in the uterus, block the baby’s descent when the baby is up high in the abdomen and passing through the vagina for delivery,” said Dr. Linda Bradley, Gynecologic Surgeon, Professor of Surgery, Vice Chair of OB/GYN & Women’s Health Institute, and Director of the Center for Menstrual Disorders, Fibroids, and Hysterscopic Services at the Cleveland Clinic in Cleveland, Ohio, who wasn’t involved in the study. “When this happens, it’s called an obstruction of labor and might give reason for a cesarean section.”
Further studies have shown that women with fibroids in the lower part of the uterus are more likely to have a cesarean section than those with fibroids in other locations.2
Dr. Bradley went on to explain that the type of fibroid could also indicate risk. “Intramural fibroids that grow within the muscular wall of the uterus or subserosal fibroids that grow on the outer wall of the uterus might be the ones that cause problems,” she explained. “These types can basically create a distortion of the uterus and a malpositioning of the fetal head as it’s descending into the vagina.”
Although there are concerns regarding complications associated with cesarean birth, current guidelines don’t suggest surgically removing fibroids during pregnancy, or as a preventative action before conceiving, as the complications related to fibroid removal may outweigh the risks linked to cesarean delivery.1
That being said, the odds of fibroids actually obstructing natural delivery are low.
“Data suggest that there’s a much higher prevalence—around 60 to 80 percent—of women with fibroids who deliver vaginally. Through ultrasound we see that most of these fibroids don’t grow large enough to create a disturbance in labor,” Dr. Bradley emphasized. “There’s nothing a patient has to do except the prenatal care that is normally recommended during pregnancy.”
ABOUT THE AUTHOR Alicia Armeli is a Health Freelance Writer, Registered Dietitian Nutritionist, and Certified Holistic Life Coach. She has master’s degrees in English Education and Nutrition. Through her writing, she empowers readers to live optimally by building awareness surrounding issues that impact health and wellbeing. In addition to writing, she enjoys singing, traveling abroad and volunteering with her local animal shelter.
ABOUT THE DOCTOR Linda Bradley, MD is an internationally recognized gynecologic surgeon, professor of surgery, Vice Chair of OB/GYN & Women’s Health Institute, and Director of the Center for Menstrual Disorders, Fibroids, and Hysterscopic Services at the Cleveland Clinic in Cleveland, Ohio. As founder of the Celebrate Sisterhood program and recipient of the American College of Obstetricians and Gynecologists Pete and Weesie Hollis Community Service Award, Dr. Bradley is dedicated to empowering multicultural women to take charge of their health, embracing self-care, and creating positive change in the world.
- Michels, K. A., Velez Edwards, D. R., Baird, D. D., Savitz, D. A., & Hartmann, K. E. (2014). Uterine leiomyomata and cesarean birth risk: a prospective cohort with standardized imaging. Annals of Epidemiology, 24(2):122-126. doi: 10.1016/j.annepidem.2013.10.017
- Cook, H., Ezzati, M., Segars, J. H., & McCarthy, D. (2010). The impact of uterine leiomyomas on reproductive outcomes. Minerva Ginecologica, 62(3):225-236.