A fully dilated cervix is 10 centimeters open. This is about the size of a bagel, and means that when your cervix is measured with two fingers, they can be stretched 10 centimeters across.
During the transition phase of labor, the cervix dilates to the following sizes: 8 cm, the size of an apple. 9 cm, the size of a donut. 10 cm, the size of a large bagel.
If one fingertip fits through your cervix, you're considered one centimeter dilated. If two fit, you're two centimeters dilated.
4 cm dilated is when the two fingers are approximately 1 cm apart. The widest stretch of the two fingers is about 7 to 8 cm. At 10 cm (full dilation), the cervix should not be present in front of the presenting fetal part (typically the head).
(Some OBs will go ahead and break your water at 3 or 4 centimeters.) The reasoning behind this: “Artificial rupture of membranes” (popping a hole in the amniotic sac) will usually jumpstart labor by getting serious contractions underway.
The second stage of labor begins once you are fully dilated to 10 cm. Your provider will let you know that it is time to start pushing your baby out. This stage can be as short as 20 minutes or as long as a few hours.
Doctors have to wait until the cervix is at least 4 centimeters dilated before doing an epidural. Otherwise, the epidural will slow the process down too much. However, once the cervix becomes fully dilated it is too late for an epidural to be given.
The cervix generally needs to be dilated to 10 centimeters before it's ready for the baby to pass through. Your cervix can be dilated to a couple of centimeters for a few weeks before delivery. This softening can cause the mucus plug to be dislodged and come out.
Early dilation often feels like menstrual cramps as the cervical changes cause pain and cramping noticed in the lower part of the uterus. It is the same sensation and location as menstrual cramps. Active labor tends to be felt in a larger area but can be a similar sensation as cramping (with more intensity of course).
During active labor, your cervix will dilate from 6 centimeters (cm) to 10 cm. Your contractions will become stronger, closer together and regular. Your legs might cramp, and you might feel nauseated. You might feel your water break — if it hasn't already — and experience increasing pressure in your back.
Transition phase
It usually takes from 15 minutes to an hour for the cervix to dilate from 8 to 10 centimeters. Contractions are 2 to 3 minutes apart and last about 1 minute. You may feel pressure on your rectum and your backache may feel worse.
The transition phase
In this phase, your cervix will finish effacing and dilate to the full 10 centimeters. This phase may take anywhere from 10 minutes to two hours.
When your baby is ready to begin the journey through the birth canal, your cervix dilates from fully closed to 10 centimeters. This process can take hours, days, or even weeks. But once you hit active labor – about 6 cm dilated – it's usually just a matter of hours before you reach full dilation.
The baby typically starts pushing stage at “0 station” (midpelvis). The baby moves lower than 0 station when pushing iss effective (+1, +2, +3 where baby becomes visible between contractions and +4 when crowning).
0 station: The baby has descended to the point that the head has reached the bottom of the pelvis. This is the point at which the baby is said to have dropped and is fully engaged. +3 station: The point in labor at which the baby's head is beginning to emerge from the birth canal.
Most of the time, you can walk within a half hour or so of your epidural injection. However, you will not necessarily be walking normally at this point. Most clinics and hospitals monitor you for 15 minutes to an hour after an epidural injection. During this time, they will likely ask how you feel.
The potential for a quicker labor, delivery and recovery – For some people, a natural birth may go more quickly. While it depends on several different factors, like how relaxed you may be, in some cases medications can interfere with contractions and prolong labor.
You'll likely still feel the pressure of your contractions (which will be helpful when it's time to push) and be aware of (but not bothered by) vaginal exams during labor. And you'll still be able to feel your baby moving through the birth canal and coming out.
Aside from pooping, moving through the different stages of labor may bring a whole host of other bodily fluids, from pee to amniotic fluid. During labor, you may pee a lot, especially if you get an IV at the hospital.
The second stage of labor starts after your cervix has dilated (opened) to 10 centimeters (about 4 inches), and it continues until your baby finishes moving through your vagina and is born. During this time, you will push or bear down (like you do when you have a bowel movement) to help your baby come out.
But if you're close to 10 centimeters dilated the research suggests it's not an issue. Evidence suggests it's more of a theoretical fear that just adds additional stress and in some cases results in an epidural (or a higher dose of epidural) to mask that urge.