Q&A: Pelvic floor during and after pregnancy: What to expect

Dear Mayo Clinic: I'm pregnant with my first child, and I've heard a lot about pelvic floor changes during pregnancy and childbirth. I'm a bit worried and curious about what to expect. Can you explain these changes and offer advice on preparing for a healthy pelvic floor after pregnancy?

Answer: Pregnancy and childbirth are transformative experiences for a woman's body, affecting it in many ways. One of the areas that may be affected is the pelvic floor, which is the diaphragm of the pelvis. These muscles support the uterus, bladder, large intestine and rectum.

Often, these muscles are affected by pregnancy and childbirth, altering some of their vital functions. These can include fecal and urinary continence mechanisms and support of the vaginal walls and uterus. Less support can lead to prolapse, when organs shift within the pelvis. Trauma to the pelvic floor muscles and nerves also may result in pelvic pain symptoms occurring with or without sexual intercourse.

Here are some of the factors that can affect your pelvic floor during pregnancy and childbirth and how they can lead to pelvic floor disorders in the future:

• Physical changes. About 50% of pregnant women experience symptoms of pelvic floor disorders even before childbirth. During pregnancy, women tend to gain weight—not just the baby's weight but also weight from the placenta, increased blood volume and an enlarged uterus. The extra weight increases strain on the pelvic floor muscles, resulting in an increased risk of urinary incontinence. Constipation is common during pregnancy, especially in the third trimester. The weight of the growing uterus and hormone changes can affect digestion, leading to infrequent or difficult passing of stools. Any related straining and stress can weaken pelvic floor muscles and nerves further.
• Hormonal changes. The body also undergoes significant hormonal changes during pregnancy that affect pelvic floor health. The placenta secretes the hormone relaxin to increase the flexibility of ligaments in the pelvis and soften the cervix. These changes are good because they prepare the body for birth. However, this can loosen the connection between the pelvis bones and lead to increased flexibility and instability.
• Medical and occupational history. Some women are more susceptible to pelvic floor disorders, and this risk increases with pregnancy. Women with a history of chronic constipation, connective tissue disorders or smoking are at increased risk. Women who are obese or have a history of repeated heavy lifting, either at work or through weight training exercises, also can be at increased risk.

Labor and delivery are considered risk factors for pelvic floor disorders. Vaginal delivery, in particular, is regarded as the most significant risk factor. During childbirth, the pelvic floor muscles undergo tremendous stress, especially during the second stage of labor, when patients are actively pushing. This risk is increased with operative deliveries using vacuum or forceps.

Labor before a cesarean section delivery also increases a woman's risk for pelvic floor disorders.

Some women's pelvic floors are more resilient and able to recover quickly, while others may be more prone to lasting issues. Studies show that the more vaginal deliveries a woman has, the more likely she is to experience pelvic floor dysfunction.

It's important to remember that pelvic floor disorders are not a forgone conclusion during pregnancy. Just as pregnant women take prenatal vitamins and avoid alcohol to lower the risks of some congenital conditions, they can take steps to reduce the risk of pelvic floor disorders.

Regular exercise and eating a healthy diet are good for your baby and good for your pelvic floor as well. I also recommend that you consider attending birthing classes before childbirth. Often, these include stretching and breathing exercises to help coordinate the diaphragm and pelvic floor muscles during delivery.

Pregnancy yoga and perineal massage can help prepare your pelvic floor by improving the flexibility and stretchability of tissues to limit your risk of perineal injuries at delivery.

When done correctly, Kegel exercises strengthen the pelvic floor muscles. About 40% of people don't perform a Kegel correctly the first time. A physical therapist can help you identify the correct muscles if you are uncertain or have questions.

Finally, talk with your OB-GYN and health care team about your concerns. They can recommend stretches and classes to prepare your pelvic floor for childbirth.