Most women, about 60 percent of us, have a biological child. And while the birth of a child is often eagerly anticipated at the end of pregnancy, there are common concerns about the impact and process of delivery. Women worry about all kinds of things. We worry about poor pain control, long labor, deviating from a carefully crafted birth plan, vaginal tearing, and pooping on the floor. Obstetricians have other concerns. They worry about bleeding, infection, shoulder dystocia, and preeclampsia. But no one is worrying about the pelvic floor.
Obstetricians are trained to look for visible damage after a vaginal delivery. It is standard practice to diagnose and treat vaginal lacerations after a delivery. ACOG has a bulletin about the prevention and management of obstetrical lacerations1. Vaginal tearing after delivery is common and happens in most (50 to 80 percent) deliveries. The vast majority of these visible tears are minor and easy to repair. Only 4 percent of vaginal deliveries have a clear tear involving the anal sphincter. But what about tears that can’t be seen?
The pelvic floor has to go through miraculous changes to allow a vaginal delivery. Studies have shown that the viscoelastic properties are so altered at the time of delivery that parts of the levator ani muscle stretch 300 percent. Think about this crazy feat- the muscle stretches three times its resting length and then resumes its previous length! No other muscle in the female body can do this, and no muscle in the male body can do this. There is no other time in life when this can happen. But in some deliveries, the levator ani stretches and then tears. It does not recover and is permanently damaged. Current estimates are that 19 percent of women have a levator ani tear after a vaginal delivery.
It is not currently standard practice to evaluate the pelvic floor muscles after delivery. There is no practice bulletin about levator muscle assessment or damage after a delivery. These muscles are often recovering in the postpartum period and may function poorly, making physical exams an unreliable tool. An intact muscle will continue to functionally improve with time. However, imaging techniques like MRI and 3D perineal U.S. can be used to visualize the pelvic floor muscles and any sustained damage. While all postpartum women do not need this evaluation, many do. It is not reasonable to assume all damage will just spontaneously heal after a delivery. The burgeoning data in this field does not support this assumption, even if it is a widely held belief in obstetrics.
This may seem like a lot of worry for a defect that most women don’t realize they have. However, pelvic floor dysfunction has a multifactorial etiology and often occurs over decades. A woman with a tear in her levator ani is seven times more likely to develop prolapse than a woman with an intact pelvic floor. Right now, there are around 3,000,000 million deliveries in the U.S. per year. This means that approximately 570,00 levator ani tears occur per year in the U.S., most of which are unrecognized. As someone who cares for women with prolapse and bladder leaking, I know that women are eager to minimize the progression of their pelvic floor injuries. And many women have suspected for years that something was different about their functional pelvic anatomy. Women should know when their bodies are structurally damaged. This helps to explain pelvic symptoms, it allows for improved patient education, and it helps guide treatment. Most women do not realize that this damage can occur during delivery and education needs to be better.
We understand birth injuries better than ever, but there is still so much that needs to be done. We need to identify who is at risk of a levator injury and employ tested risk mitigation strategies. We won’t be able to prevent all levator ani tears, so we need to determine how to best treat these muscle injuries to minimize the future impact on pelvic floor function. In doing so, we could reduce the prevalence of pelvic organ prolapse.
As Jill Biden pointed out when she announced funding for women’s health research in early 2024, “Research on women’s health has always been understudied and underfunded.” Pelvic floor dysfunction like prolapse and incontinence is seen as an older woman’s affliction. The incidence is five-fold higher in an octogenarian than a 30 year old. But while symptoms often start later in life, the seeds for pelvic floor dysfunction are sown when we are young. We need to do more to stop them from blossoming.
In the meantime, women at high risk of a levator tear or who have ongoing pelvic floor symptoms after delivery deserve more care. Such tears are more common in older moms, with larger babies (more than 4,000 g), with forceps deliveries, when the baby presents with occiput posterior, and when there is prolonged pushing. Additional care could include referral to a postpartum perineal clinic (clinics that are being developed across the U.S. and specialize in obstetric trauma), pelvic floor physical therapy, or urogynecology. We should all be worrying about the pelvic floor a little bit more.
Sarah Boyles is a urogynecologist.
