Just as every pregnancy is different, every delivery is unique. Some women get no clues that labor is around the corner, and then -- wham! -- here it comes. Others have telltale signs for weeks, maybe even a false start or two, before the real thing begins.
The simple truth is, there's no way to predict exactly when you'll go into labor. In fact, no one even knows for sure what triggers the big event, although hormones are thought to play a part. Still, there are at least six concrete clues that your baby is preparing to make his or her grand entrance into the world.
1. Lightening: You can breathe easy again.
"Lightening" is the technical term for the point when your baby drops lower in your belly and settles deep in your pelvis. For first-time moms, lightening can occur a few weeks before your baby's birth; for second-timers it may take place only a few hours before labor begins. You may feel the baby drop, or you might notice that there is now space between your breasts and abdomen.
The good news here is that you may get some relief from the shortness of breath you've been experiencing, since this shift takes pressure off your diaphragm. The bad news is that it puts more pressure on your bladder, so you may be visiting the bathroom more than you ever thought possible. Some mothers feel more pressure on their pubic bones or can even see in the mirror that their belly has lowered after lightening; others may be unaware of any difference.
2. Effacement: Your cervix ripens.
Your cervix -- the lower, narrow end of the uterus that protrudes into the vagina -- softens as it's preparing for labor. This process, known as "ripening" or effacement, usually begins during the last month of your pregnancy. By the time the big day rolls around, your cervix will have stretched from around 1 inch in width to paper thinness. Your doctor or midwife may start checking for gradual effacement during your last two months of pregnancy with internal exams during your prenatal visits. Effacement is measured in percentages: Zero percent means no effacement; 100 percent means you're fully effaced.
3. Dilation: Your cervix opens.
As your baby's birthday approaches, your cervix begins to dilate, or open up. Dilation is checked during a pelvic exam and measured in centimeters (cm), from 0 cm (no dilation) to 10 cm (fully dilated). Typically, if you're 4 cm dilated, you're in the active stage of labor; if you're fully dilated, you're ready to start pushing. Your health practitioner will probably check for dilation and fill you in on your progress during your prenatal visits in the later stages of your pregnancy.
4. Bloody Show: Your mucus plug dislodges.
It's not as gross as it sounds, nor as bloody. Although it's termed the "bloody show," this telltale sign of impending labor occurs when the thick plug of mucus that seals off your cervix and prevents bacteria from entering the uterus during pregnancy gives way. Despite its name, the "mucus plug" doesn't resemble a cork (there will be no popping sound!). It's more like thick or stringy discharge that you may pass in a clump into the toilet or your underwear. The discharge can appear as pink, brownish, or slightly bloody in color. The bloody show usually debuts either a few days before your labor starts or at the very beginning of labor, although many women go into labor before it appears.
5. Rupture of membranes: Your water breaks.
Not everyone will have the dramatic "Oh my God, my water just broke!" scene from a Hollywood movie. The fact is, when the sac of amniotic fluid that surrounds and protects your baby during pregnancy breaks, it's more likely to leak from your vagina in a gentle trickle than it is to break the floodgates. The so-called "rupturing of the membranes" can happen at the very start of labor or during the first stage of labor. Usually the doctor, midwife, or nurse will break your water before you become completely dilated, if it hasn't broken by then. This allows them to learn if you have any problems that would impede the baby's safe delivery. Contractions usually become much more intense after your water breaks, and the labor goes faster.
Your physician or midwife should evaluate you and your baby as soon as possible after your water breaks. That's because the baby is at risk of developing an infection in the uterus once the protective fluid is gone. Doctors also advise that women not have sex after their water breaks to avoid introducing any bacteria into the uterus. Your practitioner will want you to have your baby within a day or two after your water breaks.
If you are close to your due date, your water breaks, and you don't go into labor on your own within a relatively short period of time, you will need to have labor induced. If your labor doesn't begin within a specific time period, your physician may want to bring on (induce) labor. How long your health practitioner is comfortable waiting before inducing will depend on your individual situation.
Be sure to tell your health care team if your "water" isn't clear. If your amniotic fluid is greenish in color or smells bad, it could signal either an infection or meconium (essentially baby feces), either of which could cause problems for your baby. Also, if you're leaking liquid but aren't sure whether it's amniotic fluid or urine (some pregnant women leak urine at the tail end of their pregnancies), you should have it checked by your health practitioner so you know what you're dealing with.
6. Consistent contractions: When your labor really gets going.
Contractions are strong, rhythmic, regular cramps that feel like a bad backache or extreme menstrual pain. These little doozies, if they're the real thing, are the most reliable of all the signs and officially mark the onset of labor.
A contraction occurs when your uterus tightens and then relaxes. Real contractions usually start in the back of your body and move toward the front. These movements open the cervix and help push the baby into the birth canal. True contractions come closer and closer together in a predictable pattern and last around 30 to 70 seconds each. They get steadily stronger and keep coming, regardless of what you do.
You and your health practitioner should come up with a game plan ahead of time about when you should call and what you should do if you suspect you're in labor. Most practitioners will probably tell you to call when you have contractions that last for around one minute and occur every five minutes for about an hour, but this could vary greatly depending on your health history and past pregnancy record. Women who have given birth before may have a quicker labor the second or third time around, so it's important not to wait too long to call if you think things might go quickly. Be sure to discuss this with your doctor or midwife. To time the frequency of contractions, start at the beginning of one and count until the beginning of the next one.
You should definitely call your practitioner if:
- You are less than 37 weeks pregnant and are showing any signs of pre-term labor.
- Your water breaks or you think you're leaking amniotic fluid.
- You have vaginal bleeding, fever, or severe or constant pain.
- Your baby stops moving or begins to move less.
When in doubt, call your practitioner. Even if you're not sure if your signs add up to the beginning of labor, it doesn't hurt to check in. Your doctor or midwife can give you concrete advice and help you determine if this is the moment you've been waiting for. Congratulations!
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