Labor contractions are well known (and feared) but what is not known so much is that, throughout pregnancy and especially in its final stretch, there are other types of contractions that women notice with greater or lesser intensity. How to differentiate labor contractions? Below we explain everything you have to know about the different contractions and know when the time has come for your baby to be born.
For the baby to cross the birth canal, this physiological process is necessary. In other words: there is no labor without dilation and for dilation there must be labor contractions (another issue is cesarean delivery, of course).
What are contractions (and what are they for?)
The uterus where the fetus is lodged is a bag-shaped muscle. It is made up smooth muscle cells that contract involuntarily, without the woman being able to do anything to control or relax them. Uterine contraction is sensitive to hormonal changes during pregnancy, and estrogen, oxytocin or prostaglandins can influence it.
There are two fundamental changes in the body of the pregnant woman so that contraction of the uterus can occur. While progesterone levels decrease gradually, thus facilitating uterine contractions, at the same time estrogen levels increase, making the uterus more predisposed if contractions can be generated.
In Babies and more I am pregnant and my belly gets hard, what is the reason?But what really triggers this type of uterine contractions is the presence of oxytocin (the "birth hormone" favors the entry of calcium into muscle cells, an essential element in muscle contraction) and prostaglandins (also cause muscle contraction smooth; they form in the uterus itself and contain semen in low quantity).
Given the importance of hormones in triggering labor, if it is delayed, mediated induction can be recommended. But remember that the induction of labor, according to WHO should be limited to certain medical indications and in no case should it exceed 10% of deliveries.
The clearest sign that you are experiencing a contraction is tightening of the abdomen. If they are true labor contractions, you will also feel pain.From the 20th week of pregnancy, the uterus is usually trained for the birth process thanks to the "false", physiological or Braxton Hicks contractions. The uterus contracts its muscles preparing for the actual contractions that will help the baby go through the womb at the time of delivery. Thus, beginning the previous processes of cervical or cervical eradication and dilation, labor is being helped before it actually begins.
Actually, we are in the first phase of labor, the phase of early or latent dilation, which consists of this softening of the cervix, which can reach 3 or 4 centimeters (and it should be so to have part of the way route: we arrive at the birth with those centimeters "of advantage" and with the neck of the uterus erased, that is, already thinned and shortened).
In the last ten weeks of pregnancy there is a phenomenon that will help more frequent contractions appear: the uterus increases more slowly than the fetus. As a consequence there is a distension of the uterine wall that reflexively causes a greater secretion of oxytocin in the hypothalamus and consequently a slow but progressive increase in uterine activity (it is the so-called "Ferguson-Harris reflex").
The prostaglandin hormones, released for example with ruptured membranes, are also very important for the first effective contractions of labor that push the pelvis fetus down to the cervix to begin. When the fetus descends, a process that releases the hormone oxytocin in large quantities and the reflex is triggered
We are in the next phase of labor: active dilation, when the contractions gradually open the diameter of the cervix until it reaches the 10 centimeters of dilation necessary for the baby to be born.
False contractions and labor contractions
Next we will learn to differentiate false contractions from those of childbirth.
"False" contractions or Braxton Hicks contractions They are those that prepare the organism for birth. They occur especially in the third quarter. The first contractions that the pregnant woman perceives as a tension in the belly (they are not painful and last for a short time) are irregular, usually occurring at the end of the day or after some effort.
For some women there may be a sensation of pain similar to a cramp or menstruation, but mild. And although they can be noticed from the second half of pregnancy, for many women they will not be clearly noticeable until the end of pregnancy. It is then, when the time of delivery approaches, when the frequency of contractions increases.
In Babies and more, how will I know that I am in labor? Unambiguous symptoms that the day has comeThe body is preparing better for the big moment, but these contractions are still not regular or very intense, such as those of childbirth, although they can cause some discomfort.
Between one and the other contractions the presence of another type is sometimes indicated, "preparto contractions": they are more intense contractions than those of Braxton Hicks but they are not those of the labor itself, they begin to be more frequent and can cause some discomfort, without being rhythmic. And how do I differentiate them from contractions that start labor?
At one point, true childbirth is triggered. Until recently it was not known exactly when the mechanism of the onset of labor is triggered and there are several theories. It seems that this mechanism that starts labor is a signal that comes from the lungs that communicates that they are already mature and ready to start breathing outside the uterus.
Then, thanks to a complex of synchronized biological factors between mother and baby, they would start the true labor contractions, those that indicate that childbirth is already here, have particular characteristics:
- They are stronger and, therefore, more painful. The pain grows in intensity as the dilation becomes more evident.
- They are increasingly regular and rhythmic contractions, that is, they are repeated with less variable intervals.
- Labor contractions intensify with activity (rather than lessen as with false contractions), and do not disappear when resting or changing positions.
- They last longer and longer (between 30 and 70 seconds).
- Labor contractions are perceived as cramps in the lower back or as intense menstrual cramps.
- They can be accompanied by abdominal cramps and diarrhea.
- The pain can be located in the abdomen and lower back or spread to the legs (although this can also happen in false contractions, in labor the pain is much more intense).
These labor contractions are usually accompanied by other signs that indicate that the baby is about to be born, as we will see in the next section. But without a doubt they will be easily recognizable to you, since they are sensations never before experienced in pregnancy.
When the thing gets serious and the dilation increases, in the hospital many women decide to opt for the pharmacological relief of pain, as with the epidural, and there are also some natural methods to relieve pain, such as freedom of movement, techniques of relaxation ... and of course breathing.
Labor Day is coming
Pregnant women like to predict that the baby is about to arrive. How to do it, how to know the day is coming? There are several signs that childbirth is approaching, such as the baby's face, a growing sensation of pressure in the pelvis and rectum, expulsion of the mucous plug ... One of these signs is the intensification of Braxton Hicks contractions. This type of "false" habitual contractions can become more frequent, intense and even painful.
But it will not be until you have rhythmic, progressive and intense contractions that arrive at a rate of two or three contractions every ten minutes, when it is time to go to the hospital: that is when the cervix must have begun its dilation (which has to reach ten centimeters so that the baby can go through it) and labor begins.
As soon as you notice these contractions, the great moment has arrived: there is very little left for you to meet the baby. But, can labor begin without contractions? If the amniotic sac (source, water or bag rupture) is broken without previous contractions, something that happens around 15% of cases, it is normal that, again, they appear sooner or later contractions Labor: Most women will go into labor spontaneously after 24 hours.
Prior to Braxton Hicks contractions and labor contractions, there are other types of contractions, milder and generally imperceptible and there are also postpartum contractions, which help the uterus to expel the placenta (birth phase) and recover its usual size after the expulsion phase, when The baby is already born.
Then, you will have already experienced the different types of contractions and it won't be hard for you to tell them apart if you've already had a baby. "The worst" has passed and the effort has been worth it, we already have our boy or girl.
Photos | iStock
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