The uterus is a muscular organ that contracts powerfully to squeeze your baby out, and those contractions are the primary source of labor pain. How much pain you experience depends on a variety of factors, including the strength of your contractions (this increases during labor); whether you had Pitocin, which causes stronger contractions; your baby's size and position in your pelvis; whether she's faceup or facedown (the ideal birth position); and the speed of your labor.
Besides intense muscle tightening throughout your abdomen and, sometimes, your entire torso and pelvic area, you may feel pressure on your back, perineum, bladder and bowels.
"All that combines to ratchet up pain," says Jay O'Brien, M.D., medical director of inpatient obstetric services at Women and Infants Hospital of Rhode Island in Providence.
A combination of genetics and life experiences determines your pain threshold, or ability to withstand pain, and this also plays a part. Social support (or lack of it), fear, anxiety and even the positive or negative labor stories you've heard can contribute to your perception of pain. What's more, you probably can't change your inborn capacity to withstand pain.
So if your threshold is low, consider lining up a labor helper now. Studies show that women who give birth with a supportive doula or midwife report less use of pain medication, fewer Cesarean sections and greater satisfaction with their birth experiences than women who don't.
"When a woman feels vulnerable and in pain, a doula can help her feel cared for, which extends her capacity to handle labor," says Seattle doula Penny Simkin, co-author of Pregnancy, Childbirth, and the Newborn: The Complete Guide.
Labor pain usually comes on gradually and builds up as you progress through the stages of labor. Here's what to expect:
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Length: Up to 6 hours or longer
What's happening: Your cervix dilates, or opens, to 3 centimeters to 4 centimeters and begins to thin (efface). Typically, mild-to-moderate contractions last 30 to 60 seconds and occur every five to 20 minutes, becoming stronger and occurring more frequently.
Length: Approximately 2 to 8 hours
What's happening: Contractions continue to become longer, stronger and closer together, and your cervix dilates to 7 centimeters. This is when most women request pain medication, though sometimes it's given earlier.
Length: Up to 1 hour
What's happening: Pain tends to be strongest as your cervix finishes dilating to 10 centimeters. In addition to intense, closely spaced contractions, you may feel pain in your back, groin, even your sides or thighs, as well as nausea.
Length: A few minutes to 3 hours
What's happening: Intense pain is eclipsed by major pressure as you feel a great urge to bear down and push your baby out—some women describe it as "like pooping a watermelon or bowling ball." Although pain continues, many women say it's a relief to push because it helps relieve the pressure. When the baby's head crowns, or becomes visible, you may experience a burning, stinging sensation around the vaginal opening as it stretches.
Even if you opt for an epidural or other medication, using relaxation techniques can boost your ability to handle the pain, says Leslie Ludka, C.N.M., director of midwifery at the Cambridge Health Alliance Hospital and Birth Center in Massachusetts.
"Tensing up just gets in the way of labor progress," she explains.
Rhythmic breathing, visualization, meditation, self-hypnosis and other relaxation strategies taught in classes such as Lamaze, Bradley Method or HypnoBirthing may help keep your mind calm and your muscles loose. Said mom Amorette Drexler, "I was very intent on focusing on what the contractions were doing for me—opening me up to deliver my son!—and not on what the pain felt like."
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"At first it felt like intense gas pains," said mom Kelly Domitrz. "Once I figured out it was labor, it was the focused yogic breathing that I had practiced throughout my pregnancy that really worked."
Other effective techniques include massage, walking, taking a bath or shower, and applying ice or heat. Drexler found that changing positions made a big difference. "My husband worked with me weeks ahead of time to practice relaxation, massage and positions to relieve pain—using a ball, curling into Child's Pose and squatting," she said.
"When I was in active labor, the best relief came from taking a long, warm shower," said mom Megan DiGregorio. "Being able to walk around was also a real lifesaver."
Whether you plan to use pain medication or go natural, try to be flexible. "No one really knows what she will need until she is actually having the experience," says Ludka. "Give yourself permission to change your plan whenever you need to."
Also keep in mind that each option has its advantages. While medication can take much of the pain out of giving birth, delivering naturally can give you a great sense of accomplishment.
"After the pain and effort are over, you're left feeling very empowered," Simkin says. Her advice: "Differentiate between pain and suffering. Pain can be managed, but if it becomes overwhelming, medication may prevent suffering."
Some women feel guilty if they opt for labor-pain medication, as though they've somehow failed or put their babies' or their own well-being at risk. In fact, epidurals and other pain-relief drugs are quite safe, says William Camann, M.D., director of obstetric anesthesia at Brigham and Women's Hospital in Boston and co-author of Easy Labor: Every Woman's Guide to Choosing Less Pain and More Joy During Childbirth.
"There's lots of misinformation—the risks and complications are overblown, and women suffer unnecessarily," he says.
What's more, the benefits of epidural may last long after your baby is born. According to Gilbert Grant, M.D., director of obstetric anesthesia at New York University Langone Medical Center and author of Epidural Without Guilt: Childbirth Without Pain, there is a connection between unrelieved childbirth pain and postpartum depression, post-traumatic stress disorder, and chronic pain.