PERINEAL CARE AND OUTCOMES IN A BIRTH CENTER

Objective: to analyse the perineal outcomes in childbirth and post-partum perineal care in a freestanding birth centre. Method: a cross-sectional study, with data collection performed in the women’s birth records forms from Casa Angela, a freestanding birth centre, São Paulo, Brazil, in 2016-2017 (n=415). The following data was analysed: occurrence and perineal tear degree; maternal, neonatal and birth care-related variables; perineal suture prevalence; complications in wound healing and natural methods on perineal care. Data were subjected to descriptive, inferential and multiple analyses. Results: in 11.8% of women, the perineum was kept intact, 61.9% had spontaneous first-degree tear and 26.3% had second-degree tear. The variables related to the occurrence and higher spontaneous degree tears were maternal age and second period of childbirth >2 hours. The protective factors against the occurrence and higher degree tears were number of previous vaginal childbirths and maternal position different from vertical during childbirth. Perineal suture was performed in 16.0% and 70.6


INTRODUCTION
It is estimated that more than 85% of women had some kind of perineal trauma during childbirth, caused by episiotomy or by the spontaneous rupture (tear or laceration) of tissues during the baby's passage through out the vagina. 1 Spontaneous perineal tears are classified in degrees according to the tissue layers affected.First-degree tears only reach the skin and mucosa, second-degree tears also reach the musculature, third-degree tears affected the anal sphincter and fourth-degree tears harm the rectal mucosa. 2 Complications associated with perineal trauma may harm women's health both in the immediate and long term post-partum period, affecting their mobility, vesical and intestinal elimination, general care towards the newborn and other daily activities. 32][3][4] Episiotomy, on the other hand, may cause more severe pelvic floor damages, just as third-and fourth-degree tears. 4ome maternal and newborn characteristics may be related to higher occurrences and degree of spontaneous perineal tears. 5The place of birth, professionals who provide care and their practices also affect the degree of perineal tears and perineum care after childbirth. 6herefore, Birth Centres (BC) were built as a strategy to change the hospital environment where childbirth takes place, reducing unnecessary interventions.They are classified as alongside when inside hospital's facilities, or freestanding (FBC) when in the surroundings of the reference hospital. 7rofessionals working in BC adopted practices to keep the physiology of labour and childbirth, respecting woman's autonomy.] Thus, this study aimed to analyse perineal outcomes and postpartum perineal care in an FBC.

METHOD
A cross-sectional retrospective study, conducted at Casa Angela FBC, in São Paulo, SP, Brazil.Casa Angela provides antenatal, childbirth and post-partum care and, since 2016, has a contract signed with São Paulo City Hall to receive financial resources from the National Unified Health System (Sistema Único de Saúde -SUS).
The study population was made of all women admitted for birth at Casa Angela.A total of 467 women were admitted between January 2016 and June 2017 and characterized, and 415 of them took part of the study sample.
Data collection happened between July and December 2017 and was performed through the analysis of the institution women's records and childbirth, maternal and neonatal transfers' book records.The data collection instrument contained items related to maternal, neonatal and labour/ childbirth care characteristics, as well as data concerning post-partum period during women's stay and after discharge.
For "occurrence" and "spontaneous perineal tear degree" outcomes, the following variables were considered as exposure: maternal age, skin colour, previous vaginal childbirths, oxytocin administration, warm compress during the second stage of labour, position during childbirth, duration of the second stage of labour, water birth, shoulder dystocia, newborn weight and newborn cephalic perimeter.For "perineal suture" outcome, the variable considered exposure was spontaneous perineal tear degree.For "perineal complications" outcome, suture and spontaneous perineal tear degree were considered exposure.
For continuous variables, data were analysed using the mean value and standard deviation (SD).For categorical variables, data were analysed by means of absolute and relative frequencies.In the bivariate analysis, for the association between exposure variables and outcomes were used 4/12 chi-square, Fisher's exact, Kruskal-Wallis tests and variance analysis (ANOVA).For the analysis of the association between postpartum perineal complications, perineal suture and tear degree, it was used chi-square test.Odds ratio (OR) and its respective 95% confidence interval (95%CI) were also calculated.In the bivariate analysis, variables showing a p-value<0.20 were inserted in a binary (perineal integrity and spontaneous tears) or ordinal (tear degree) logistic regression model.The type I error adopted was 5%.

RESULTS
Between January 2016 and June 2017, 467 women were admitted in labour at Casa Angela.Among these, 52 (11.1%) were transferred intra-partum to a hospital.Therefore, the study's final sample was 415 women.All of them had uncomplicated pregnancies, no morbidity or related risk factor and were admitted in labour between 37 and 42 gestation age.
Most of them were having their first pregnancy (n=268; 64.6%), with a mean of 1.5 (SD=0.7)pregnancies per woman; the mean of previous vaginal births was 1.2 (SD=0.6)and only 2.6% (n=3) had a previous caesarean section.
The mean value of cervical dilation on admission was 5.6cm (SD=2.4).Interventions such as amniotomy and oxytocin administration were used exceptionally, in 6.5% (n=27) and 6.3% (n=26) women, respectively.The woman's choice companion was present in 99.5% (n=412) of childbirths, with a mean of 1.6 (SD=0.6)companion per woman.The second stage of labour, most of the times, lasted up to 1 hour (n=319; 76.9%).As for the position during childbirth, almost one third of women gave birth in the semi-seated position (n=127; 30.8%), followed by squatting position (n=82; 19.9%), seated position (n=75; 18.2%), and four support position (n=70; 16.9%).Water birth happened in 32.4% (n=134) of the births; however, the births happened in many places in the birthing room (delivery bed, exercise mat or bed sheet on the floor, childbirth stool, shower).
Shoulder dystocia happened only once (0.2%); in 3.4% (n=14) of the births, newborn Apgar score was below 7 in the first minute, there was no Apgar score below 7 in the fifth minute.Newborn weights ranged from 2,310g to 4,180g, with a mean of 3,240.1g(SD=372.0)and newborn cephalic perimeter ranged from 31cm to 38cm, with a mean of 34.3cm (SD=1.3).
As for the perineal outcomes, the perineum was kept intact in 11.8% (n=49) of women.The prevalence of women with spontaneous first-degree tears was 61.9% (n=257), followed by 26.3% (n=109) with spontaneous second-degree tears.In cases of multiple traumas (tear or laceration), only the higher trauma was considered.There were no cases of spontaneous third-and fourth-degree tears, as well as episiotomy.Given that, there were women with multiple traumas; 448 traumas were recorded and distributed according to their perineum location: 37.5% (n=168) were located at labia minora, 36.2% (n=162) at perineal body or posterior vaginal wall, 16.7% (n=75) at vestibule and 9.6% (n=43) at anterior vaginal wall.
The bivariate analysis showed that perineal integrity was more frequent when the duration of the second period of labour was up to 1 hour, and spontaneous second-degree tear was more frequent when this period exceeded 2 hours (p<0.001).In its turn, the following categorical variables showed no statistically significant association with perineal outcome (integrity and spontaneous firstor second-degree tears): skin colour (p=0.222),oxytocin administration (p=0.955),warm compress during the second stage of labour (p=0.691),maternal position during childbirth (p=0.052) and water birth (0.196) (Table 1).Continuous variables that did not show association were the following: maternal age (p=0.190),number of previous vaginal childbirths (p=0.173),newborn weight (p=0.591) and newborn cephalic perimeter (p=0.439)(Table 2).

5/12
All variables with p-value <0.20 in the bivariate analysis were included in the multiple analysis of the perineal outcome "occurrence or not of perineal tear" and "perineal tear degree", as referred in the Method section.
Concerning maternal age, the chance of spontaneous perineal tear increases by 4% each year.As for the duration of second stage of labour, when it was over 2 hours, women had 2.8 times more chance to have perineal trauma.In both situations, not only the chance of having a tear or laceration increased, but also the chance of them being a spontaneous second-degree tear (Table 3).
In its turn, previous vaginal childbirth is a protective factor for perineal tear, since each previous vaginal childbirth decreases in 56% the chance of perineal tear.As for the position during the second stage of labour, women that gave birth in non-vertical positions had less chance to have perineal trauma than those who gave birth in squatting, standing or kneeling positions.In lateral position, the 6/12 chance of having a trauma was 67% lower, in four support position, 56% lower and in seated and semiseated positions, 51% lower.In all of the above situations, not only the chance of tear or lacerations decreased, but also the chance of them being of spontaneous second-degree tear (Table 3).Regarding post-partum perineal suture, most of spontaneous first-degree perineal tear were not sutured (n=216; 84.0%).The opposite happened with spontaneous second-degree tears, most of which were sutured (n=77; 70.6%) (p<0.001).
Regarding complications, pain and edema were the most frequent ones, referred by 53.6% (n=144) and 29.4% (n=79) of women, respectively.The chance of feeling pain was higher when the tear was sutured, apart from the degree (OR=2.1;95%CI 1.1-3.9;p=0.029).The chance of perineal edema was also higher in cases of perineal suture for both first-and second-degree (OR=2.5;95%CI 1.4-4.2;p=0.002).
Natural methods of perineum care applied in post-partum were used in 51.8% (n=215) of women.Even if women had used one or more methods (n=259), local application of icepack was prevalent (n=139; 53.8%), followed by calendula compress with or without icepack (n=95; 36.6%).For medications after childbirth, scopolamine, acetaminophen or sodium diclofenac were taken only by 24.1% (n=100) of women.

DISCUSSION
In this study, maternal age was associated to perineal trauma; each year increased the chance of perineal tear.4][15] Women in this study were mainly in their first pregnancy; however, after the multiple analysis, the chance of spontaneous perineal tear decreased for each previous vaginal childbirth.
A prolonged second stage of labour is clearly stated in the literature as an associated factor to the occurrence of perineal trauma.][15] In this study, the association between the duration of the second stage of labour and perineal outcomes also agrees with the literature.The rate of intact perineum decreased when the duration of the second stage of labour increased.Such is also the case with spontaneous first-and seconddegree tears: the longer is the duration of the second stage of labour, the higher is the frequency of spontaneous perineal tears, and higher is the degree.
It is worth mentioning that in the place of this study, women have freedom to adopt any position during childbirth; therefore, there was a lot of positions and places chosen by the women for having the birth: squatting, seated, four supports, lateral, standing and kneeling.Only one woman gave birth in supine position.
Supine position may be associated with abnormalities in fetal heart beats, higher rates of episiotomy and lower prevalence of spontaneous vaginal childbirth.Vertical positions, in its turn, may reduce episiotomy rates, duration of the second stage of labour and occurrence of instrumental birth.][18] Just as demonstrated in the literature, in this study, vertical positions increased the chance of spontaneous second-degree perineal tear and reduced the rate of intact perineum.
Regarding lateral position, it can increase perineal integrity rates, reduce the occurrence of episiotomy, labia lacerations and local edema; besides, when compared to other positions, it contributes to the reduction of spontaneous second-degree tears. 16The same outcome was shown in a controlled randomized trial regarding four support position. 18

8/12
Likewise, in this study, there was higher rate of intact perineum when women adopted lateral or four support positions during childbirth.Other than these, seated and semi-seated positions were protective against perineal tears when compared to vertical positions.
The model of maternity care, mainly care during childbirth, may produce impact on perineal outcomes.The continuity of care provided by midwives and nurse midwives in an FBC favours a considerable reduction in episiotomy rates, since it contributes to a physiological childbirth, with discerned use of interventions and better maternal and neonatal outcomes. 19s showed in the literature, in FBC setting there are better perineal outcomes, with higher rates of intact perineum or spontaneous first-degree tears and smaller proportions of episiotomy. 7,20n this study, tears were first-degree mainly and, more than half was not sutured.
In spontaneous first-and second-degree tears, the recommendation from the Brazilian Ministry of Health and National Institute for Health and Care Excellence (NICE), UK, is that all spontaneous second-degree tears and those first-degree with non-apposed edges may be sutured for the sake of better wound healing. 2,21t is possible to assume, considering the childbirth model of care adopted in the place of this study, that professionals use interventions wisely.The perineal suture performance is an example, since that 67.7% of the tears were not sutured.
In the literature there are indications that leaving the skin with no threads may decrease perineal pain and dyspareunia, but there are no long-term studies concerning if this conduct could cause damages regarding healing in the following months or years.Apart from that, there is no highquality evidence involving the non-suturing of first-and second-degree tears to confirm the safety of this practice. 1n our study, performing or not performing suture was also analysed relating to the most common perineal complications: pain, edema, ecchymosis and others described in women's records.In general, there was a higher proportion of complications in sutured tears: 58.2% of sutured firstdegree tears and 70.1% of sutured second-degree tears.
2][3] In this study, women who had perineal suture, had higher frequency of pain, both in first-and second-degree tears.Edema was also higher in these women.
After childbirth, it is possible to reduce discomforts caused by perineal trauma with pharmacological and non-pharmacological methods.Pharmacological methods like anti-inflammatory medicines and painkillers are prescribed by health professionals for pain relief, but these medications has side effects, such as gastrointestinal, bleeding and allergic reactions. 22However, even though these side effects may occur, medicines are predominant for pain relief. 23n the other hand, the medicine overuse can be managed with the use of non-pharmacological methods for pain relief. 3In this study, natural perineal care methods were used in a little more than half of women.Local icepack compress is the most used practice and demonstrates effectiveness to relieve perineal pain. 24Other methods used, such as calendula tincture and chamomile tea compress, appear in the literature as capable of greatly increasing the speed of perineal wounds' healing. 25he results of this study contributes to the knowledge about maternal and childbirth care factors that may influence the occurrence of perineal tears, apart from contribute to describe post-partum perineal care.It also brings subsidies to improve perineal practices of health care professionals to women during childbirth both in BC and hospital settings; which may result in better perineal outcomes.
Given that the literature is not conclusive about the advantages and disadvantages of suturing first-and second-degree tears, in relation to healing process and perineal complications, more research on safety in not performing sutures is necessary, given its possible benefits.

9/12
The limitations of this study are especially about the data collected from women's records and cross-sectional design.The information obtained was recorded by Casa Angela's professionals, depending exclusively on its quality and level of detail.
Apart from that, the analysis of the perineal care methods, use of medication and perineal complications in post-partum was global (without discrimination of the moment of its occurrence), that is, a longitudinal analysis of these variables was not performed.

CONCLUSION
Regarding perineal outcomes, there was prevalence of spontaneous first-degree tears which happened with more than half of women.The ones of second-degree happened with more than one quarter of women.No woman had episiotomy.
The variables related to the occurrence and to a higher spontaneous perineal tear degree were: increased maternal age, lower number of previous vaginal childbirths, duration of the second stage of labour over 2 hours and vertical positions during childbirth.Lateral, four support, seated and semi-seated positions are protectors against the occurrence of spontaneous perineal tear.
The perineal suture of first-degree tears was performed in a low number of women, while not all of those with second-degree tears were sutured.In its turn, perineal complications (pain and edema) in post-partum period were more frequent when suture was performed, regardless the tear degree.
Natural perineal care methods after childbirth were used in a little more than half of women; the prevalent ones were icepack compress and calendula tincture, with or without ice.

Table 3 -
Initial and final model of the multivariate analysis of the relation between spontaneous tear occurrence and maternal and birth care variables.São Paulo, SP, Brazil, 2016-2017