Care during the second stage of labor

Physiological considerations

During the second stage of labor, fetal oxygenation is progressively reduced, the expulsion of the fetus from the uterus and uterine contraction resulting in a reduction in placental flow. Furthermore, strong contractions and expulsive efforts may further reduce the uteroplacental flow. The decrease in oxygenation is accompanied by acidosis. The rate and severity of this process differ substantially from person to person and the caregiver should carefully monitor the fetal condition.

Beginning of the second stage

The beginning of the second stage is characterized by the following symptoms:

- the woman feels the urge to push because the amniotic sac or presentation exceeds the dilated cervix and presses against the rectum
- often there was spontaneous rupture of membranes;
- dilation is usually complete, but sometimes the woman feels the urge to push at an earlier stage of expansion. If there is persistence of a cervical collar, it will be rejected by the presentation.



It appears from the foregoing that does not always know exactly when the second stage begins. A woman may feel the urge to push before the expansion is complete, as it may not feel this need despite the diagnosis of full dilatation. If full dilatation was assessed by vaginal examination, the question remains to know how long it is complete.

In some hospitals it is customary to transport the woman to the labor ward in a "delivery room" at the beginning of the second stage. The delivery room is usually equipped with large bright lamps, instruments, and a delivery bed fitted with brackets and clamps or metal gutters for the lithotomy position. Although this framework is more convenient for the obstetrician in case of vacuum extraction, all unnecessary transport is unpleasant for the woman. In a normal delivery, it is not necessary to change the room's wife early in the second stage. The labor and delivery can easily be monitored in the same room.

The early thrust forces during the Second Stage

Midwives often decide early second stage by encouraging woman to push when full dilatation has been diagnosed, sometimes even earlier. The physiological approach is to wait until the woman feels herself the urge to push. Once full dilatation, this need does not always feel and simply wait ten or twenty minutes for the second stage of labor starts spontaneously. There are no controlled trials comparing early onset and late onset of thrust in a normal delivery, but the tests were carried out in parturients under epidural analgesia.

The thrust reflex is suppressed, it is easy to postpone this effort until the top is visible in the hole. This method was compared to that of pushing from what the diagnosis of full dilatation. The thrust late do not seem to have had a negative effect on fetal and neonatal outcome. The early thrust was accompanied by a significantly increased number of forceps delivery. Although these results were obtained in women who gave birth under epidural analgesia, they coincide with the clinical experience of midwives differ pushing up the spontaneous thrust reflex. This practice is easier for women and it tends to shorten the expulsion phase.

When the woman begins to grow, or just before, it is sometimes advisable to systematically empty the bladder through a catheter. This practice is unnecessary and can cause infection of the urinary tract. During the second stage, when the fetal head is firmly committed, the catheterization can be very difficult, even traumatic. It is advisable to encourage the woman to urinate spontaneously during the first stage of labor, for a normal delivery, this practice is usually sufficient.

The thrust forces during the Second Stage

The practice of encouraging continuous thrust forces and directed during the second stage of labor is frequently advocated in many delivery rooms. The other method is to encourage spontaneous expulsive efforts women (push blower). Both practices were compared in several trials. Spontaneous pushing resulted in three to five thrusts relatively short (4-6 seconds) with each contraction, compared to the thrust forces sustained 10-30 seconds, accompanied by an inspiration blocked.

The latter method has the effect of reducing somewhat the second stage of labor, but it can cause alterations in heart rate and stroke volume. It may be associated with compression of the aorta and reduced uterine blood flow when the woman is lying on her back. In published studies, the average pH of the umbilical artery was lower in the groups where the investigation had been sustained, and Apgar scores tended to be lower. Based on limited data available, it appears that the thrust forces and supported early lead to a slight reduction in the duration of the second stage, which does not seem to match any particular advantage, it also appears that this negatively affects the gas exchange between mother and fetus. The thrust spontaneous as possible, seem to be superior.

In many countries, the practice of pressure on the fundus while the second stage of labor is common. It aims to accelerate delivery, and is sometimes used shortly before delivery, even early in the second stage. Besides the issue of increased maternal discomfort, it is suspected that this practice is harmful to the uterus, the perineum and the fetus, but no research has been done on this issue. However, it appears that this method is used too often, without having proved its usefulness.

Duration of second stage

In 1930, De Snoo determined the duration of the second stage of labor in 628 primigravidae with cephalic presentation in childbirth. He observed an average of one hour and a quarter, with a median of one hour. These values were strongly influenced by the occurrence of some very long periods (10-14 hours). Since the average duration of second stage was largely determined by the artificial termination of employment after the period allowed by the caregiver. Primiparous women, the average duration of second stage is now frequently reported as being about 45 minutes. The association between a prolonged second stage and fetal hypoxia or acidosis led to shorten the second stage of labor, even in the absence of maternal or fetal problems evident.

This policy has been controlled trials. The work stoppage after an uncomplicated second stage led to a significant increase in the pH of the umbilical artery, without other evidence that this policy has been beneficial for the baby. The maternal trauma and fetal trauma due to occasional increased use of instruments not assume that this policy can hardly be justified. If the mother and fetus are in good condition and if the work progresses, there is no reason to want to strictly observe a stipulated duration of the second stage, one hour for example.

Several monitoring studies have been published on the status of the newborn according to duration of second stage. In the study of Wormerveer a cohort of 148 neonates was examined on the basis of the pH of the umbilical artery and neurological score in the second week of life. The duration of the second stage of labor ranged from less than 60 minutes (66% of nulliparous) and 159 minutes. No relationship was found between the duration of second stage and the status of the newborn. A follow-up study on 6759 infants of nulliparous in vertex presentation and weighing over 2500 g was recently published, the second stage of labor lasted over three hours in 11% of cases. No relationship was found between the duration of second stage and a low Apgar score 5 minutes, the convulsions of the newborn, or admission to an intensive care unit for newborns.

In conclusion, the decision to discontinue the second stage of labor should be based on monitoring the condition of the mother and fetus and on the progress of labor. If signs of fetal distress or if the descent of the presentation is not done, it is justified to terminate the work, but if the mother's condition is satisfactory, that the fetus is in good condition and that the descent of the fetal head appears to progress, there is no reason to intervene. However, after a second stage of more than two hours in a nulliparous and over an hour in a multipara, the probability of spontaneous delivery within a reasonable time decreases and should be considered an interruption of work.

Throughout the world, in industrialized countries as in developing countries, the number of deliveries requiring instrumental delivery increased significantly in recent decades. The exact causes are unknown but apart from the already mentioned strict adherence to a second stage to a stipulated duration, the incidence of operative can be influenced by fear of malpractice suits, for the convenience or the input gain. According to research conducted among obstetricians and residents in the Netherlands, the presence of midwives in a hospital dampen the tendency to intervene more frequently. The presence during childbirth professionals not qualified to intervene, but eager to maintain normalcy, apparently can prevent unnecessary interventions. The global epidemic of operative requires particular attention because any unnecessary intervention is dangerous for the woman and the newborn.

Maternal position during the second stage

A number of trials showed that the vertical position or a bank angle in the second stage of labor was preferable to the supine position. The vertical position is less uncomfortable and easier to push and it reduces the pain of labor, perineal trauma / vaginal infections and lesions. According to a test, the vertical position would have to shorten the second stage. In terms of fetal outcome, trials have reported a reduced number of Apgar scores below 7 in a vertical position.

The vertical position, with or without birthing chair, can promote the labial tears and the results although very few, show an increase of third degree tears. There was an increase in postpartum haemorrhage in women who adopted the upright position. The cause is not yet established but it may be that the vertical position allows more precise measurements of blood loss, the difference could also be due to increased pressure on the veins of the pelvis and vulva. In one trial, the hemoglobin level was below the fourth day after birth, although the difference was not very sensitive.

The position of the mother during the second stage of labor affects the fetal condition as the first stage. The research showed a reduction in the frequency of abnormal heart rhythms in a vertical position and a general increase in the pH of the umbilical artery. In some trials, women were asked to say which position she preferred; enthusiasm was greater for the vertical positions, less painful and save more back. Lithotomy position with legs in stirrups was experienced as less comfortable and more painful and restricted movement. Women who had given birth in this position would choose the vertical position in the future.

The positive effect of the vertical position depends to a large extent the capacity of the obstetrician / midwife and experience positions other than the supine. Some knowledge of benefits and willingness to help women in various positions can change at any job at all.

In conclusion, whether the first or second stage, women may take the position they wish although it is preferable to avoid prolonged periods in supine position. They should be encouraged to try the position that is most comfortable for them and they should be supported in their choices. Obstetricians / midwives need training to supervise and carry out deliveries of women who chose positions other than the supine position so as not to inhibit the choice of position.

Perineal care

Perineal injuries are one of the most common injuries in women during labor or during labor and delivery that are considered normal. There are many techniques and practices to reduce these injuries, or to reduce them to manageable proportions.

Protect the perineum during childbirth

Many books describe the practice to protect the perineum during the delivery of the head of the fetus: the fingers of one hand (usually right hand) support the perineum while the other hand relies on the fetal head to control the speed of release, thus trying to prevent or reduce tissue injury of the perineum. This maneuver can prevent perineal tear but it is also possible that the pressure on the fetal head deflection hinders the movement of the head and make it deviate from the pubic arch to the perineum, thus increasing the risk of injury the perineum. In the absence of formal evaluation of the strategy or the strategy on the contrary not to touch the perineum or the head during this stage of labor, it is impossible to decide which strategy is best.

The practice of protecting the perineum through the hands of the obstetrician is easier to apply on a woman in a supine position. If the woman is upright, the obstetrician / midwife may support the perineum blindly or be obliged to follow the strategy of "do not touch".

Another technique to reduce the risk of perineal trauma involves massaging the perineum during the last part of the second stage of labor, and to try to relax the tissues. This technique has never been properly evaluated but may raise doubts as to the advantage of a sustained friction tissues already highly vascularized and edematous.

Other maneuvers on which there is not enough evidence about their effectiveness are the various methods used to clear the shoulders and abdomen of the newborn after delivery of the head. It is not certain that these maneuvers are not always necessary that they are appropriate. There is no research on this topic. However, the National Perinatal Epidemiology Unit at Oxford undertook a randomized controlled trial of "care of the perineum at delivery with or without hands" which should provide data on the effect of different methods for clearing fetal head and shoulders on the perineum (McCandlish 1996)

Vaginal tears and episiotomy

The perineal tears are common, especially in primigravidae. Some tears in the first degree does not even require suturing; second degree tears are usually easy to suture with local analgesia and, in general, they heal without complication. The third degree tears may have more serious consequences and should, where possible, be sutured by an obstetrician in a hospital well equipped to prevent fecal incontinence and / or fecal fistula.

Episiotomies are commonly performed, but the incidence is varied. United States of America, for them 50 to 90% of women delivering their first child, making the episiotomy the most common surgical procedure in this country. In many centers, there is a policy of "cover", mandating for all primiparous episiotomy. In the Netherlands, the overall incidence of episiotomies performed by midwives is 24.5%, 23.3% of which are mediolateral and 1.2% median. The median episiotomies are easier to suture and they have the advantage of leaving less tissue scarified, while mediolateral episiotomies more effectively help prevent anal sphincter and rectum. The reasons for an episiotomy during childbirth until then normal are: signs of fetal distress, insufficient development of labor and threatened third-degree tear (including a third-degree tear during a previous delivery).

These three values are valid although it is very difficult to forecast a third-degree tear. The incidence of third degree tears is about 0.4% and the diagnosis of "threat of third-degree tear" should be only occasional, otherwise the diagnosis does not make sense.

Besides the reasons mentioned above, several other reasons, the existing literature, justifying the unrestricted use of episiotomy: it replaces an irregular laceration by a straight, neat surgical incision, it is easier to repair and it heals better than a tear, it prevents severe perineal trauma, trauma to the fetal head and lesions of the pelvic floor muscles, and therefore the stress urinary incontinence.

Evidence to support these benefits put forward for the routine use of episiotomy have been several randomized trials. The data from these trials do not support this policy. Use at every turn of episiotomy is associated with increased rates of perineal injury and a decrease in the number of women with an intact perineum. That the use of episiotomy is based on rigorous criteria or not, all women have felt the same pain of the perineum 10 days and 3 months after delivery. There is no evidence that episiotomy has a protective effect on the fetal condition. A follow-up study extending over a period of three years after the birth did not establish that the widespread use of episiotomy had affected urinary incontinence. An observational study on 56 471 births by midwives, showed an incidence of 0.4% of third degree tears in the absence of episiotomy and a similar incidence associated with mediolateral episiotomy; incidence associated with midline episiotomy was 1.2%.

The health care provider who performs an episiotomy should be able to suture tears and episiotomies properly. It must have the necessary training. An episiotomy should be made and sutured under local anesthesia, with proper precautions against HIV and hepatitis

In conclusion, there is no evidence that reliably widespread or systematic use of episiotomy has beneficial effects, but obviously it can be harmful. In a previously normal childbirth, an episiotomy may sometimes be justified, but it is recommended to restrict the use of this intervention. The percentage of episiotomies performed in the English test (10%) without risk to mother or child should be a goal.