What Is Dilation, Effacement, and Station in Pregnancy?
Your doctor or midwife will start checking your cervix(cervical) for effacement, dilatation, and station around your 37th week of pregnancy. Many new and experienced mothers are unsure what this entails. If reports like “one centimeter, 25%, -2” leave you perplexed, this explanation of effacement, dilation, and station will keep you informed at your next checkup.
Effacement
When the cervix(cervical) softens and thins, it is called effacement. The cervix(cervical) dilates, which implies it opens. During labor, both dilatation and effacement occur, and both are required for your baby to pass through the delivery canal. Your cervix dilates and effaces from 0 to 100 percent during labor. This can take a few hours, days, or even weeks to complete. You’re ready to birth your baby once dilatation and effacement are finished.
Doctors and midwives usually measure effacement in percentages. When you undergo an exam, your provider will inform you if it is 0% effaced (no effacement at all) or 100% effaced (completely effaced and thin). Your cervix becomes part of the uterine wall when it is totally effaced, and your mucus plug is loosened, allowing the baby to pass through.
Cervical effacement symptoms and signs
As your cervix effaces, you may or may not experience symptoms. Some women experience no symptoms at all. Some women may experience irregular contractions, which are uncomfortable but not painful as labor contractions.
Other possible symptoms or signs includes:
- Loss of mucus plug
- Increased vaginal discharge
- The sensation that your baby has dropped lower into your pelvis
It is important to keep in mind that you will experience many sensations at the end of your pregnancy. Your symptoms may be difficult to determine if they are caused by dilation, effacement, early labor, or just general aches and pains.
What does 50 percent effaced mean?
You might hear your healthcare practitioner state something like, “You’re 50% effaced,” while you’re in labor. This just implies that your cervix has thinned to 50% of its original thickness, which is termed totally effaced. So, if you hear this from your doctor, you’re halfway to 100 percent effacement.
What does 60 percent effaced mean?
Your cervix is 60% effaced when it is short and thin enough to allow your baby to pass through the uterus. The majority of effacement occurs during the early stages of labor, when your cervix has dilated to 6 cm, and can take several hours or even days.
What does 70 percent effaced mean?
When your cervix is 70% effaced, it’s on its way to becoming short and thin enough to allow your baby to pass through the uterus. This happens when your cervix is dilating to 6 cm in the early stages of labor, and it might take several hours or even days.
What does 80 percent effaced mean?
If you say you’re “80 effaced,” it indicates you’re 80% effaced. You’re only 20% away from being completely effaced, at which point you’ll be ready to birth.
Dilation
The term “dilation” refers to the opening of the cervix. Your cervix should stay tight and closed with no dilation until late into your third trimester. This keeps bacteria away from your precious cargo. As you get closer to delivery the mouth of the cervix opens and widens, allowing your baby to pass through. This is measured in centimeters. For most of your pregnancy it should be 0 centimeters, opening to 10 centimeters when it’s time deliver. As the cervix dilates, some people describe cramping and pressure, similar to what you would feel during menstruation. Yay for labor pains!
Each woman’s cervix thins and opens at her own pace. The cervix may begin to efface and dilate slowly in certain women over a period of weeks. However, a first-time mother may not dilate until active labor begins.
Your health professional may use his or her fingers to check the cervix late in your pregnancy to assess how much it has effaced and dilated. He or she will do so while wearing sterile gloves.
The contractions in your uterus open (dilate) your cervix during labor. They also aid in positioning the baby for birth.
If you begin dilating in the second trimester or at a rapid rate before the last month of your pregnancy it can be a sign of premature labor. If this is the case your doctor or midwife will advise you on what to do.
When do you start dilating?
As your due date approaches, you should start dilating in the 9 month of pregnancy. Every woman’s time is different. Dilation and effacement might be a slow process for some people, taking weeks or even months. Others can dilate and efface in a matter of hours.
What happens when I’m 1 cm dilated?
When your cervix is 1 cm dilated, your body is either preparing for labor or is already in the early stages of labor. It’s impossible to predict how much longer your cervix will dilate. It might only take a few hours. However, it could take several days or even weeks.
What happens when I’m 2 cm dilated?
Being two centimeters dilated, like being one centimeter dilated, does not indicate that labor is near. Some women with a dilated cervix of 2 cm may go into labor within hours. Others will stay 2 cm dilated for a few days or weeks before labor starts.
What happens when I’m 3 cm dilated?
When your cervix reaches 3 cm dilation, you’ve probably entered the early stages of labor. During this stage, your cervix gradually widens to around 6 cm. Most often, this takes between 8 and 12 hours and can take anywhere from a few hours to a few days.
During the early stages of labor, you may experience:
- A progressive increase in the strength and frequency of contractions
- Your water breaking
- Mucousy vaginal discharge (from the dislodged mucus plug), if it didn’t happen earlier.
What happens when I’m 6 cm dilated?
Your cervix will dilate from 6 to 10 centimeters (cm) during active labor. Your contractions will get stronger, more regular, and closer together. It’s possible that your legs will cramp and you’ll feel sick. If your water hasn’t already broken, you can notice an increase in pressure in your back. Now is the time to visit your labor and delivery facility if you haven’t already.
As labor develops and your discomfort increases, don’t be shocked if your initial excitement wanes. If you require pain medicine or anesthesia, request it. Your medical team will work with you to help you make the greatest decision for you and your baby. Remember that you are the only one who can determine whether or not you require pain relief.
Baby Station (Fetal Station)
When your provider talks about your baby’s station (fetal station), she’s talking to how far down into your pelvis your baby’s head has gotten. A negative station is measured in centimeters when your baby has dropped but has not yet nestled into your pelvis to begin his or her descent. The range of this negative value is -3 to -1. It’s called a zero (0) station after your baby has nestled into your pelvis but before he starts his descent down the birth canal. It’s called a positive station from 1 to 3 when your baby starts going towards the cervix. You will most likely experience increased pressure and pain in your pelvic bone and vaginal area during this period. Again, yay for labor!
In the weeks leading up to delivery, it’s important for a mom-to-be to know where her baby is positioned and how her body is complying. Some doctors will check but not tell you unless you specifically request it. Don’t be shy about asking if you haven’t been told or if you haven’t been offered a cervical exam.
What is Baby Lie/Fetal Lie
This term refers to how the baby’s spine lines up with the mother’s spine. Your baby’s spine is between his head and tailbone.
Usually, your baby will settle into a position in the pelvis before labor begins.
- If your baby’s spine runs parallel to yours, it is said to be in a longitudinal lie. This position is common for most babies.
- Transverse lie occurs when the baby is sideways (at 90-degrees to your spine).
What is Baby Attitude/Fetal Attitude
The fetal attitude(baby attitude) explains the relationship between the fetus’ bodily parts. The head is pulled down to the chest, and the arms and legs are drawn in towards the center of the chest in the normal fetal position.
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