Unlike in the movies, labor and delivery isn't always scripted. No one knows exactly what triggers labor, though hormones are suspected to play a role. And though labor is divided into three stages, each woman may not go through it the same way. For first-time moms, labor can last 12 to 24 hours on average. For some women it will be faster and for others slower. Here's what you need to know.
Stage One: Latent Phase
What to expect: This stage of labor is the longest and can range from 12 to 20 hours for women having their first baby. Labor begins when you have uterine contractions -- which may be mild at first, occurring every 15 or 20 minutes -- and when your cervix begins slowly dilating and effacing (thinning). It ends when your cervix is dilated 3 or 4 centimeters (about 1 to 1 1/2 inches).
Contractions last anywhere from 30 to 70 seconds and can feel like a backache or menstrual cramps. As labor progresses, contractions become more regular, frequent, and intense, increasing to every seven to 10 minutes, then every five to seven minutes.
What to watch for: You may notice a "bloody show," pink or brown-tinged mucus -- a normal discharge as your cervix opens. This discharge may happen days before or at the start of labor.
The rupturing of amniotic membranes can occur spontaneously in stage one labor or later in the process and feel like an obvious gush or just a feeling of wetness -- or your water may not break until a doctor does this for you, says Tiffany A. Moore-Simas, MD, MPH, MEd, FACOG, director of the Obstetrics and Gynecology Research Division at the University of Massachusetts Medical School.
How to manage: It's good to call your doctor when you begin contractions, but you may not need to go to the hospital yet. Healthy, first-time moms can usually go through this stage of labor at home, says Moore-Simas. When should you go to the hospital? "When you're contracting every five minutes, that's a good time to come in," says Moore-Simas. "If you're leaking fluid, that might [also] be the time to come in."
Meanwhile, rest and make yourself as comfortable as possible, perhaps by listening to music or soaking in a warm bath.
Stage One: Active Phase
What to expect: At this stage, contractions are stronger and more painful, occurring about three minutes apart and lasting approximately 45 to 60 seconds. Your cervix is dilating much more rapidly, about 1.2 centimeters an hour, says Moore-Simas.
When your cervix dilates from 8 to 10 centimeters, you are in "transition stage," the last part of stage one labor; contractions now come approximately every two to three minutes and last for a minute or more. You may feel nauseous and have increased back pain.
How to manage: At the hospital, your vital signs (temperature, blood pressure, pulse) will be taken. External monitors to check the baby's heart rate and your contractions will usually be placed on your abdomen. A nurse or doctor will do an internal exam to check dilation.
Practical tips: Warm showers, particularly with a hand-held showerhead, can help reduce lower back pain. Gently bouncing on a birthing ball, receiving massage from a partner, listening to soothing music, and practicing deep breathing exercises can also help. Some women find relief by changing positions, walking, or getting down on their hands and knees.
What to expect: Often called the pushing stage, this part can last up to three hours if you've had an epidural -- up to two hours without it. At 10 centimeters (about 4 inches), you're fully dilated. Contractions may last longer than a minute and will usually occur every two to three minutes. As the baby's head descends into the pelvis/vagina area, you may feel pressure in your rectum (like the need to have a bowel movement) and the urge to push.
How to manage: "You don't ever want to push until somebody has told you you're fully dilated," says Moore-Simas. Otherwise, pushing can cause the cervix to swell. "Often the pushing happens in spurts of three over the course of one contraction," she says. "You take a big, deep breath, and you want to push like you're really constipated, with all your effort in your bottom."
If necessary, you may have an episiotomy, a small cut in the area between the vagina and the rectum to ease delivery. This practice isn't done as much as it once was, says Moore-Simas, who estimates only 5% of her patients require episiotomies.
The progress of the baby's descent through the pelvis is measured in numbers called stations until the baby crowns (when the top of baby's head becomes clearly visible at the opening of the vagina).
What to expect: The shortest stage of labor can take moments or last for 30 minutes. Contractions won't be as strong as you deliver the placenta (or afterbirth). If you have an episiotomy or you've torn tissue during delivery, you will be stitched up now.
Labor may be different for every woman, says Moore-Simas. But "at the end of the day, the goal is a healthy mom and baby. It's such a beautiful day and such a beautiful experience."