INTRODUCTION

Labor and birth represent the end of the pregnancy, the beginning of extrauterine life for the newborn and a major change in family life.

Childbirth is the most expected moment of transition and, at the same time, the most feared by the couple. This is a process experienced with much anxiety that must be recognized by the midwife, with the aim of providing the necessary support in overcoming the feelings of anxiety and fear, allowing the couple to live a natural moment of their life - the birth of their child.

In this context, it emerges the concept of Natural Labor¹, as well as the classification of common practices in natural labor assistance, including the liberal or routine practice of the episiotomy in the category “practices which are frequently used inappropriately"²⁾⁽³

Recommended when certain criteria are met, the practice of episiotomy consists in a surgical incision in the perineal region, with obstetric indication to be performed in the following situations: signs of fetal distress, insufficient progression of labor and the threat of third-degree laceration, because of the usual justification of professionals that it contributes for the severe perineal trauma prevention, uterine prolapse and urinary incontinence. Episiotomy is mainly executed in cases of: perineal rigidity, primiparity, macrosomic fetus, prematurity, pelvic presentation and eminence of perineal rupture.⁴

However, the preventive/routine use of this practice still continues to be executed despite the absence of scientific evidence to support its benefit, as well as the existence of clear evidence that it may carry some consequences for women, especially the increased rate of infection, the risk of severe perineal injury, the increased blood loss, the discomfort and longer postpartum recovery time, with implications for the establishment of the breastfeeding process.³ This, along with the recommendations of WHO, lead us to a reflexion about midwife interventions. Therefore, health professionals should seek alternative practices to prevent perineal trauma⁴.

The limited use of the practice of episiotomy contributes greatly in obtaining a positive experience of labor and in humanizing the care provided, so it should be encouraged to the detriment of its routine use. Therefore, it is estimated that the ideal frequency for this practice should vary between 10 and 30% of vaginal deliveries^1)(2)(3.

Thus, the objective of this work is to determine the available scientific evidence on the interventions of the midwife for the prevention of perineal trauma, understanding the labor as a positive, natural and human experience for the woman, the newborn and the family. Therefore, it is considered that there is a long way to go towards a more humanized practice, centered on the individuality of each couple, as childbirth assistance needs to be further explored, taking into account a greater proximity between the health professionals, the woman and the family, being the midwife a facilitator in this process.

METHOD

The approach to this problem is qualitative in nature, and it is based on the identification of articles about the interventions of the midwife in order to prevent the perineal trauma, focusing on evidence-based practice, as it promotes the development and/or use of searches results in clinical practice. It was used a methodology of literature integrative review, which allowed the search, the critical reflection and synthesis of the available evidence on the subject, aiming to determine the current state of knowledge, the implementation of interventions in practice and also the identification of limitations likely to be developed in future searches⁵.

Therefore, it is intended to contribute to the clarification of knowledge in the area of Gynecology and Obstetrics, since it is believed that knowledge provides the necessary power for change, which may result in obtaining greater autonomy.

The data collection from the selected articles was based on the methodology of the literature integrative review that includes the following steps: selection of the research question; establishment of inclusion and exclusion criteria; identification of pre-selected and selected studies; categorization of selected studies; analysis and interpretation of results; presentation of the revision/synthesis of knowledge.⁵

Therefore, the following research question was considered, which was a starting point for the construction of the integrative literature review: Which interventions can be developed by the midwife in terms of prevention of perineal trauma?

The access to evidence was obtained through the search of publications cataloged in the databases: Medline, Elsevier, Nursing Reference, Cochrane Database of Systematic Reviews and through the platform EBSCOhost and PUBmed.

We defined as an inclusion criterion the availability of original articles using the following keywords: Pregnancy; Birth; Perineum; Midwife, with full text available in Portuguese, English and Spanish, published between December 2007 and July 2015, referring to clinical trials or systematic reviews of the literature alluding to parturients regardless of parity and resulting from the search based on the descriptors and their combinations. Exclusion criteria include studies that do not meet the above inclusion criteria. This research allowed the identification and analysis of 14 articles that are represented in Table 1, which documents the data of the selected studies.

Table 1 Discription of the selected articles 

For the analysis and interpretation of the results it was considered the title; the objectives of the article, the author; the method; the level of evidence, the year and the country in order to incorporate the object of study.

RESULTS AND DISCUSSION

After the analysis of the results of the search carried out, the interpretation and consequent synthesis of the main data were made. The detailed analysis of each article resulted in the suggestion of strategies, in them identified, that were considered capable of answering the starting question, which were compared and organized according to their similarity in content and in eight empirical categories, presented in Table 1.

Physical exercise in pregnancy

Physiological responses to moderate exercise in pregnancy are generally improved compared to pregnancy without exercise. Therefore, levels of oxygen uptake, heart rate, systolic volume and cardiac output, among others, are improved, being beneficial for the mother and the fetus. Healthy pregnant women, without contraindications to exercise, should be encouraged to practice physical exercise regularly, with specific professional support to guide the exercise prescription in pregnancy and postpartum⁶.

The regular practice of physical exercise in pregnancy may reduce abdominal discomfort and constipation, as well as help the woman to sleep better and to maintain weight control, avoiding excess weight, gestational diabetes and depression. Exercises such as Pilates allow the maintenance of abdominal muscle tone, which helps to support the abdominal distension throughout pregnancy and also to increase the ability to push in the expulsive period⁷. The confirmation of these data suggests important benefits, not only for the evolution of pregnancy, but also for the evolution and results of labor. Recently, physical exercise in pregnancy has been associated with positive effects on strengthening the pelvic muscles and, consequently, with positive results in pregnancy and labor progression. Several studies have concluded that there is a lower incidence of prolonged expulsive periods, practice of episiotomy and presentation of buttocks in women who performed exercises to strengthen the pelvic muscles in pregnancy⁸.

These data are consistent with previous comparative studies on the effects of pelvic muscle strengthening exercises in three groups: a group of women who exercised less than once a week; another group that did it once or twice a week, and another group that did it at least three times a week. The results showed a lower incidence of laceration, episiotomy, instrumented delivery and cesarean section in the group of women who underwent pelvic strengthening exercises at least three times a week, thus confirming the importance of regular exercise ⁽⁹.

Also noteworthy are studies that seek to relate the effects of physical exercise in pregnancy to the type of delivery, which show a lower percentage of cesareans and instrumented deliveries in pregnant women who performed physical exercise. Based on these results, a moderate-intensity supervised exercise program performed throughout pregnancy may be recommended in healthy women¹⁰.

Perineal massage in pregnancy

Perineal trauma following vaginal delivery has been associated with significant morbidity in the short and long term. So, the perineal massage in the prenatal period has been suggested as a method to reduce its incidence. Therefore, the use of this technique in the prenatal period has been associated with an overall reduction in the incidence of perineal trauma requiring suture, concluding that women who were practicing this massage were less prone to episiotomy, especially primiparous women¹¹.

The perineal massage allows the preparation of the perineal tissues for delivery, increasing its elasticity and decreasing its resistance in distension. In its implementation, the use of lubricating gel, composed of ingredients with relaxing properties, allows the improvement of the elasticity and extensibility of the skin and the perineal muscles of pregnant women, resulting in the reduction of the risk for perineal trauma. Accordingly, there is a reduction in the percentage of episiotomies and lacerations in labor and its subsequent complications, mainly postpartum perineal pain, so it should be included in the preparation for delivery, providing information to the woman about its benefits and the technique of realization¹².

Maternal position

The maternal position emerges as an aid to the success of labor. It is important its evaluation by health professionals, as well as the comfort of the parturient since it interferes with anatomical and physiological adaptations in labor. Frequent changes in position relieve fatigue, increase comfort and improve circulation, so women in labor should be encouraged to adopt the positions they consider most comfortable¹³.

We easily understand that changing position in labor contributes to an increased maternal comfort. However, and regarding labor outcomes, can the maternal position influence the maintenance of perineal integrity?

In comparative studies that included women who were encouraged to follow a protocol of postural changes while performing spontaneous expulsive efforts and adopted lateral decubitus position in fetal expulsion, it was observed a significant reduction in instrumented delivery and in the rate of practice of the episiotomy, which significantly increased the rate of intact perineum. Therefore, it was concluded that a combination of postural changes in the passive phase in second-stage labor and the use of the lateral decubitus position in the active phase of the expulsive period (just stimulating spontaneous pushing) are associated with the reduction of instrumented delivery rates and perineal trauma¹⁴.

Spontaneous pushing

In a randomized study that compared groups of women encouraged to spontaneous pushing (keeping the glottis open) with groups of women encouraged to perform the Valsalva maneuver (keeping the glottis closed and pushing for the maximum time), it was concluded that second-stage labor and duration of the expulsive period were significantly longer in the group encouraged to perform the Valsalva maneuver. Regarding the incidence of episiotomy, perineal lacerations or postpartum haemorrhage, the differences were not significant. Neonatal outcomes were more favorable in the spontaneous pushing group, with better Apgar scores at the first and fifth minutes and with better pH and partial pressure of oxygen levels in the umbilical artery. Therefore, it is concluded that spontaneous pushing contributes to better neonatal outcomes, so it is beneficial to educate women about the spontaneous pushing technique and to support them in its implementation¹⁵.

Ritgen’s maneuver

Ritgen’s maneuver is an obstetric procedure that helps the fetal extraction (it favors the flexion of the head and facilitates its removal) and avoids violent expulsion that can lead to perineal injuries¹⁶. It is also a preventive maneuver of anal sphincter lacerations and it is performed between uterine contractions. However, in the studies of Jönsson et al.¹⁶⁾ it was used its modified version, which consists of its realization in uterine contraction rather than between contractions. Their objective was to investigate whether the modified Ritgen’s maneuver reduced the risk of third and fourth degree perineal lacerations compared to simple perineal support. The results showed that the rate of third and fourth degree lacerations was 5.5% (n = 38) in women who underwent the Ritgen’s maneuver and 4.4% (n = 32) in women who were subjected to simple perineal support. Therefore, it is concluded that the modified Ritgen’s maneuver does not reduce the risk of anal sphincter injury in the expulsive period, at least not when performed in contraction¹⁶.

Hands off technique

In randomized trials that compared groups of women submitted to the Ritgen’s maneuver, to the restriction of perineal manipulation or to the perineal massage, it was concluded that the prevalence of lacerations in the Ritgen’s maneuver group was higher and that this is associated with an increase in the degree of severity of the lacerations. There were no significant differences in the frequency of lacerations in groups submitted to the Hands off technique or to the perineal massage with lubricant. It was also concluded that the frequency of perineal pain after delivery was higher in the Ritgen’s maneuver group compared to the other two groups, between which, again, no significant differences were found. Therefore, the restriction of the perineal manipulation was associated with a lower rate of perineal trauma and contributed to a greater satisfaction in the experience of physiological vaginal delivery¹⁷.

More recently, in order to prevent perineal injuries in the delivery, a perineal protection device was developed and its efficacy was investigated through a randomized controlled trial, which goal was to evaluate the incidence of perineal lacerations and its side effects for the woman in labor and the newborn.

The results showed that the incidence of first and second degree lacerations was significantly lower in the treatment group compared to the control group, in which the device was not used. Moreover, in the intervention group, the number of women with the intact perineum was higher (34.9% vs. 26.6%) and there were no negative effects on the mother or the newborn, so this device could be a contribution in what concerns the prevention of perineal injury in delivery¹⁸.

Heat application (hot gauze compress)

According to randomized studies which had the goal to determinate the effects of the application of hot gauze compress on the perineum on perineal trauma and maternal comfort in the second stage labor, it was concluded that, despite its negligible effect in the first and second degree lacerations and in the probability of need for perineal suture, the women in the hot gauze compress application group had significantly less third and fourth grade lacerations and had significantly lower perineal pain in the first and second postpartum days. In addition, at three months, they were significantly less likely to have urinary incontinence compared to women included in the standard care group. Therefore, this simple and inexpensive practice should be associated to the assistance in the second stage labor¹⁹.

Perineal massage in labor

The perineal massage has been associated with benefits such as the reduction of stress, the increase of blood circulation and the relief of pain. Moreover, when the perineal muscles surrounding the vaginal introitus are strongly distended, the woman undergoing perineal massage with vaseline is less likely to suffer a perineal injury, since this practice contributes to a greater elasticity and softness of the tissues, helping the woman to get used to pressure sensations that are caused by the fetal presentation at the delivery.

Studies conducted with the objective of verifying the effects of perineal massage with vaseline on perineal trauma, in what concerns the rate of episiotomy practice and the rate of perineal laceration, showed a significantly lower duration of the second stage labor and a higher rate of intact perineum. There were no cases of third or fourth degree lacerations. Regarding perineal trauma, the massage has been associated with a decrease in the rate of episiotomy and an increase in the rate of first and second degree lacerations. In addition, in a follow-up study up to 10 days postpartum, the group of women submitted to the massage did not reveal any side effects of the use of vaseline. Therefore, it is concluded, that perineal massage with vaseline in the second stage labor increases perineal integrity and reduces perineal trauma (episiotomy and lacerations). Thus, it is recommended as an effective way to maintain the perineal integrity in delivery²⁰.

Empowerment, support and trust

The well-being of the newborn depends on the mother's ability to care for her child, which can be influenced by the pain due to perineal trauma, a factor that can prevent the woman from carrying out her daily activities, interfere with returning home and with her independence, affecting her self-esteem and confidence as a mother and also can have an impact on the relationship, bonding and breastfeeding. Thus, the midwife must promote effective interventions, avoiding the occurrence of negative experiences ²¹. Therefore, it is midwife’s responsibility to plan appropriate interventions for each woman and to promote their participation in decision-making related to childbirth experience (empowerment), which is not always the case.

Thompson and Miller ⁽²² examined the participation of women in the decision-making process in pregnancy and labor. The results showed that 60% of the women proposed for vaginal delivery had not been informed about the risks and benefits of the procedures they had undergone and that 34% of the women submitted to the episiotomy were not consulted in the decision making, which shows the urgent need for intervention and provision of information.

Thus, empowering women is a process that should be approached in the preparatory sessions for labor, ensuring that women are proactive in this process ⁽²¹.

Therefore, the midwife has the responsibility of empowering women, motivating the confidence in their body and their ability to undergo labor, which is a natural and physiological process and a unique experience in women's lives. Women should also be prepared to rely on the midwife as a competent professional to assist in the progression of labor ⁽²¹.

FINAL CONSIDERATIONS

Interventions of the midwife in the prevention of perineal trauma, in particular the practice of episiotomy, have to start from the beginning of pregnancy, in the prenatal surveillance visit. Thus, the woman should be encouraged to maintain or to initiate the regular practice of moderate intensity physical exercise, with the accompaniment of a professional, in the sense of the prescription of the physical exercises, taking into account the symptoms, the discomforts and the physical capacity inherent to pregnancy. The exercise program for the pregnant woman should be dynamic and regular, at least three times a week and ideally every day for at least 15 minutes, which should gradually increase to 30 minutes, up to a minimum of 150 minutes of weekly physical activity⁶.

The importance of physical exercise is reflected in health during pregnancy and labor, contributing to increase abdominal muscle tone and consequent ability to pull effectively, and to strengthen the pelvic muscles, contributing to the reduction of the time of the expulsive period and the practice of episiotomy, as well as instrumentalized delivery and caesarean section^{6)(7)(8)(9)(10}.

During pregnancy and during the preparation for delivery, usually from the 28-30 weeks of gestation, there are midwife interventions that can prevent the practice of episiotomy. These include the promotion and teaching of perineal massage, providing information on its benefits and technique, as it was associated with the reduction of perineal trauma, mainly to the practice of episiotomy, and the reduction of perineal pain after childbirth. In its implementation, the use of lubricating gel, whose lubricating properties benefit the elasticity and the perineal extensibility, is relevant^11)-(12.

During labor, the postural change of the parturient in the latent phase of the expulsive period and the use of the lateral decubitus position in the active phase of the second period were associated with reduced rates of instrumentalized childbirth and perineal trauma and so, they should be promoted and encouraged¹⁴. To these interventions, it can be added the benefit of educating/empowering women on spontaneous pushing and their support in its implementation, since this technique has contributed to the shortening of the second stage of labor and to the reduction of instrumentation, as well as to better neonatal outcomes¹⁵.

The restriction of the perineal manipulation was associated with a lower rate of complications, such as perineal lacerations and postpartum pain¹⁷.

The application of hot gauze compress to the perineum significantly reduces third and fourth degree lacerations and pain during labor, as well as on the first and second postpartum days and also has benefits in what concerns urinary incontinence and so, it should be used in assistance in this stage of labor¹⁹.

The perineal massage with vaseline during the second stage of labor not only reduces the its duration, but also increases the possibility of preservation of the perineum, mainly by reducing the frequency of episiotomy and is therefore a pertinent intervention in the practice of the midwife²⁰.

As for the Ritgen’s maneuver, it is concluded that its modified version does not reduce the risk of third and fourth degree lacerations, at least not when performed during uterine contractions, which does not mean that its original version, performed between contractions cannot do so. This means that there is still needed more evidence on this issue¹⁶.

We note that the studies involved in the integrative review advocate, in accordance with the guidelines of the World Health Organization, the most natural possible labor, as well as a reduction of intervention and a limitation of the instrumentation since it is considered to promote possibilities of occurrence of perineal trauma.

Thus, considering the research done and answering to the initial question, we consider that the intervention of the midwife on the prevention of perineal trauma should attend a sequential set of interventions: (1) To encourage the initiation or maintenance of moderate intensity physical exercise, at least three times a week, as soon as the pregnancy is confirmed; (2) To educate and to encourage the woman to perform the perineal massage, from the 30th gestational week; (3) To promote postural changes throughout labor, with the possibility of ambulation; (4) To encourage and to support the woman to spontaneous pushing during the expulsive period; (5) To promote the restriction of perineal manipulation, allowing the slow and gradual adaptation of the tissues to the fetal presentation; (6) To apply hot gauze compress to the perineum during the second stage of labor; (7) To perform gentle perineal massage using a lubricant; (8) To prefer the simple perineal support when applying the Ritgen’s maneuver, in favor of its modified, more interventional version; (9) To promote the empowerment of women and the capacities needed to make decisions about their labor, providing support and confidence.

These interventions are pointed out by the current evidence as a contribution to the prevention of perineal trauma during labor, especially in the practice of episiotomy. However, its application in the practice of the midwife requires the availability of more evidence, as well as an effective dissemination of its results to the multidisciplinary and community teams, presenting the health gains for women and the humanization of care, represented by them.

The present results reveal concerns about humanizing the experience of birth experienced by the woman, encouraging her to self-knowledge and self-control of her body and her capacities, through more naturalistic techniques, and thus contribute to a happier postpartum life³.