Second Stage of Labor
Physiologic second stage of labor occurs when a mother works with her body's impulses to give birth
Timing of the Second Stage of LaborThe second stage of labor is the period of time when the mother pushes the baby through the vagina to be born. The length is generally measured by the full dilatation of the cervix until the birth. There are, however, two other measures that may indicate second stage is near or has started.
One indication of second stage is the turning of the baby’s head to a straight anterior position, facing the mother’s back directly. The other indication of the second stage is the presence of the urge to bear down.
Ideally, all three factors: full dilatation, the rotation of the head, and the urge to bear down, should all occur at the same time. This rarely happens at precisely the same moment; generally one or two occur before the other. Some babies get into an anterior position quite early. The mother may have an urge to bear down prior to full dilatation, or she may be fully dilated but not yet have the urge to push, because the baby’s head is not low enough in the pelvis to activate the bearing down reflex.
Beginning of the 2nd Stage of LaborThis leads to a rather eccentric practice in this country. Women are “not allowed to push” until a pelvic exam is done and the announcement is made that the cervix is fully dilated. At that point second stage officially begins, the time is noted on the chart, and the woman is required to push long and hard during her contractions.
This directed pushing of the second stage of labor may include counting or giving orders to the woman--when to start pushing, how long to sustain it, mandating that she should take a breath quickly, and get right back into a hard push.
Birth attendants sometimes have a dilemma when a woman feels the urge to push: should they not report the urge to the physician and continue to forbid her from bearing down – which can be uncomfortable for her and keep her in the transition phase longer than necessary? Or should a pelvic exam be done to see if she is dilated to ten, and then pressure her to bear down long and hard, which is exhausting.
Sometimes a woman may labor down, which means she does not bear down and her body will bring the baby down the vagina without pushing. In this case much of the work of second stage will be done without the long sustained and exhausting effort of forced pushing.
The problem with all of this is it goes against the messages the woman’s body is telling her. If she has the urge to bear down before she is fully dilated, that urge is usually somewhat muted. She gives short, little pushes which help to open the stretchy cervix the last centimeter or two.
On the other hand, the head may not be fully engaged and rotated, so she may have a rest period of decreased uterine contractility for 15 – 30 minutes. This period, identified as “rest and be thankful” by Sheila Kitzinger, occurs because the head of the infant is no longer in the uterus, so the uterine muscle must remold itself around the baby’s body. The contractions in this period may be weak, difficult for the mother to discern when they begin or end, or even non-existent.
Physiologic Second Stage of LaborPhysiologic second stage refers to the concept of allowing nature’s urges to direct the woman’s efforts. After all, until a few generations ago no one ever donned sterile gloves and did a pelvic exam to announce the commencement of second stage. Women pushed how and when they felt the urge.
Directed pushing may be beneficial if the woman is anesthetized and cannot feel the urge. It may also be needed if the woman is emotionally upset and out of control. In a few situations, a medical emergency may require that her bearing down be forceful to get a compromised baby out quickly.
However, with a return to physiologic birth, the second stage seldom needs to be directed by others.
In addition to bearing down according to the body’s signal, physiologic second stage also directs the woman to assume a natural position. Again, the baby is making a complicated set of maneuvers to traverse through an irregularly shaped passage. No single position is ideal for the entirety of labor; it depends on where the baby is and how the mother is feeling.
Some mothers aid the birthing urges with the “birth hum.” This is a low deep sound from the bottom of the throat. It can be a “hnnnn” grunting sound made with the lips slightly parted. As the contraction builds, the hum often stops as the air flow is blocked at the bottom of the throat. The hum may return as the peak of the contraction passes and she completes the bearing down as the urge subsides. Some mothers feel that the birth hum helps direct their bearing down efforts.
At the same time the mother can direct her pushing efforts to the bottom of the vagina. She should visualize opening the perineum in front of the baby’s head. The birth hum brings the baby downward while the bearing down opens the passageway in front.
Positions for 2nd Stage of LaborCertainly the common practice of having a woman lie on her back is not ideal in almost any situation. A Cochrane review concluded that the upright positions for birth are advantageous and women should be allowed to birth upright.
In spite of the physiologic problems with lying on the back for delivery, it is simply a fact that many physicians are uncomfortable and unknowledgeable about any other position for the birth. A compromise that some mothers have found with physicians is to assume whatever position they find most comfortable until the baby’s head is on the perineum. Once the head is on the perineum they lie on their backs which allows greater visibility of the perineum for the physician.
Download our Brochure on Physiologic BirthOur brochure Physiologic Birth provides valuable information on the second stage of labor:
By Karen Newell Copyright 2003 - 2012 Better Childbirth Outcomes - All Rights Reserved
Camp Hill, Pennsylvania, USA