Effect of skin-to-skin contact on the placental separation time, mother’s oxytocin and pain levels: randomized controlled trial

Introduction

Implementing skin-to-skin contact (SSC) between mother and neonate is one of the powerful vagal stimulators ensuring secretion of maternal oxytocin via certain sensorial stimuli such as touch, warmth and odor [1]. The literature reports SSC has no negative impact on the health of the mother or infant and has many benefits including strengthening the immune system, decreasing anxiety, increasing self-esteem and self-confidence, and decreasing pain for the mother and decreasing gas and colic and strengthening the bond between mother and newborn for the infant [2], [3], [4]. Additionally, immediate SSC has positive effects on successful breastfeeding initiation, decreasing postpartum hemorrhage through stimulating oxytocin secretion, and facilitating adaptation to maternal roles [5], [6], [7], [8]. In addition, rising oxytocin levels during SSC induce uterine contractility, thereby allowing easier delivery of the placenta [8], [9], [10], [11], [12], [13].

Despite copious studies regarding effects of SSC on maternal and neonatal health, few studies evaluate its effects on pain level in the early postpartum period and placental separation time, and those that do exist present conflicting results. Matthiesen et al. [14], Nissen et al. [15] and Cong et al. [16] reported that SSC initiatives increase oxytocin level of mothers. However, no significant difference in plasma oxytocin level was observed between mothers who received SSC and those who did not in Velandia’s study [17], which examined the effects of maternal and paternal SSC on infants following cesarean section. Furthermore, a limited number of studies indicate SSC initiatives decrease placental separation time [4], [11], [18] and the pain level of the mother [19], [20], [21]. For this reason, the present study is expected to both contribute to the literature and create incremental awareness regarding SSC initiatives.

Materials and methods

The present study was designed as a randomized controlled trial to determine the effect of SSC between mother and infant during the third stage of labor on postpartum levels of oxytocin and pain and placental separation time.

The population of the study included the mothers who gave vaginal birth at a public hospital and their babies. Sample size was calculated based on power analysis (power and alpha error were 0.80 and 0.05, respectively). Accordingly, the calculated sample size was at least 60 women divided into groups of 30. The present study was conducted with 64 parturients: 32 in the intervention group and 32 in the control group.

Written permission from the Institution where the study was conducted and approval from the Sakarya University Clinical Research Ethics Committee of Faculty of Medicine (date/no: 20.05.2015/6194) were obtained prior to gathering data. The sample was composed of those parturients who met inclusion criteria and gave verbal and written consent to volunteer for the study after being informed. The parturients who took part in the study were assigned to groups using the randomized closed envelope method. Two papers were enclosed in two dark colored envelopes. One contained “skin-to-skin contact practice” and the other “standard care”. The participants chose an envelope containing their group assignment.

Results

There were no significant differences between women in the study and control groups with regard to age, education levels, parity, status regarding delivery preparation training, hemoglobin level, body mass index (BMI) and weight gained during pregnancy (p>0.05).

With regard to assessment of gestational weeks, 12.5% of the women in the intervention group gave birth in the 38^th, 18.8% in the 39^th and 68.8% in the 40^th gestational week. As for the women in the control group, 25.0% gave birth in the 38^th, 37.5% in the 39^th and 37.5% in the 40^th gestational week. The difference regarding gestational week when delivery occurred was statistically significant (p=0.043, p<0.05) among women in the 40^th gestational week (Table 1).

Certain characteristics of the mothers and infants in the study and control groups regarding the delivery process and the characteristics of the infants (period of travail, episiotomy application rate, labor duration, laceration development rate, gender and birth weights of the infants) were evaluated and the differences between the groups were statistically insignificant (p>0.05) (data not shown). Additionally, when the timing of the deliveries was evaluated, 37.5% of the women in the study group gave birth between 12:01 and 18:00, whereas 28.1% of them gave birth between 18:00 and 00:00. With regard to the women in the control group, 37.5% of them gave birth between 00:01 and 06:00, whereas 31.3% of them gave birth between 06:01 and 12:00. There was a statistically significant difference with regard to the timing of delivery (p=0.049, p<0.05) among women who gave birth between 06:01 and 12:00.

The mean oxytocin levels of the women in the intervention group in the 30^th min were 267.0±55.7 μIU/mL, whereas this value was 81.4±47.3 μIU/mL in the control group. The difference between both groups with regard to serum oxytocin levels in the 1^st and 30^th min was statistically insignificant (p>0.05) (Table 2). The 1^st min mean oxytocin level of the women was 275.3±55.2 μIU/mL in the intervention group and 269.9±43.7 μIU/mL in the control group. The 30^th min mean oxytocin levels of the women were 267.0±55.7 μIU/mL in the intervention group and 81.4±47.3 μIU/mL in the control group. The difference between groups with regard to serum oxytocin levels in the 1^st and 30^th min was statistically insignificant (p>0.05) (Table 2).

The distribution of the time and characteristics of placental separation are given in Table 3. The placenta separated within the first 10 min after delivery in 62.5% of the women in the intervention group and in 62.6% of the women in the control group, which was statistically insignificant (p=0.124, p>0.05) (Table 3). The mean placental separation time for women was 10.1±4.8 min in the intervention group and 9.9±3.3 min for women in the control group, which was statistically insignificant (p=0.448, p>0.05) (data not shown). Complete placental separation was observed in 90.6% of the women in the intervention group and 93.8% of the women in the control group, which failed to show a significant difference (p>0.05) (Table 3).

The distribution of the postpartum pain scores of the women is given in Table 4. The 5^th, 15^th and 30^th min pain levels of women in the intervention group were 2, 1 and 0, respectively, and in the control group were 4.5, 2 and 1, respectively. The difference between both groups for all measurements with regard to pain level was statistically significant. The pain levels of the women in the intervention group were lower compared to those in the control group for each measurement (p<0.05) (Table 4).

Discussion

Oxytocin, released within the brain from oxytocinergic nerves emanating from the paraventricular nucleus in response to activation of sensory nerves during labor, breastfeeding, sexual activity, touch, stroking and warm temperature [23]. SSC is a powerful vagal stimulant which releases maternal oxytocin through sensory stimuli such as touch, warmth and odor [1]. Many factors affect the oxytocin secretion of the mother during both delivery and the postpartum period such as the environment the mother is in, the anxiety level of the mother, the emotions of the mother regarding her baby, and the postnatal SSC initiative [5], [6], [7], [8], [9], [10], [11], [12], [13], [24]. In the present study, there was no difference between groups with regard to mean oxytocin levels at the 1^st and 30^th min (Table 2, p>0.05).

Velandia [17] conducted the only similar study identified in the literature, which examined the effects of maternal or paternal SSC with the baby after a caesarian section. It did not demonstrate statistically significant differences in plasma oxytocin levels between mothers who experienced SSC with their babies and those who did not [17].

Nevertheless, the literature reports that SSC between mothers and their babies during the early postpartum period is effective in increasing oxytocin levels of the mother [14], [15], [24]. In a study conducted by Cong et al. [16], the oxytocin levels of mothers who received SSC application were measured before (1 min prior to SSC), during (30^th min), and after (30 min after the end of SSC) SSC. While oxytocin levels before and after SSC were not significantly different, oxytocin levels did increase during SSC (on the 30^th min of SSC) [16]. In a study conducted by Matthiesen et al. [14], the contact of the baby’s hand with the breast increased oxytocin levels. The results of Matthiesen differ from the results of present study. However, the baby was placed not on the breast of the mother but on her abdomen, and thus no contact/stimulus was applied to the breast in present study. For this reason, breast stimulation, not SSC, might have caused the increase in oxytocin release in Matthiesen’s study.

In studies conducted with rats, SSC performed between rat pups and mother rats or maternal licking for a long period appeared to increase oxytocin concentrations in the pups’ plasma [25], [26]. In a study conducted by Seltzer et al. [27], the oxytocin levels of daughters were examined according to their communication with their mother after they had undergone a stress challenge. The mother-daughter couples were divided randomly into three groups: receiving support from their mothers with all stimuli, including touch, receiving support via voice (via phone), and those who did not receive any support. Voice contact increased oxytocin levels as effectively as touching [27]. Factors including not undergoing induction, giving vaginal delivery with full-term gestation, having healthy babies, having been in the same room with their babies, and seeing them positively impacted oxytocin levels of mothers in the control group, although they did not experience SSC. Additionally, eye contact with their babies and hearing their voices positively effect oxytocin levels. Thus, no significant differences with regard to levels of oxytocin were found.

Time and characteristics of placental separation is affected by many factors. The literature reports that SSC between mother and infant in the third stage of labor positively affects the placental separation via increasing oxytocin secretion [11]. Mean placental separation time of both groups did not demonstrate statistically significant differences in the present study (0.448, p>0.005). Additionally, complete placental separation occurred in almost all of the women in both groups with no bleeding problems after placental separation. Nonetheless, the study conducted by Mejbel and Ali [18] noted that placental separation occurred within the first 5 min following birth in the women experiencing SSC. Mejbel and Ali reported that 30% of the women in the case group receiving SSC and 92.5% of the women in the control group were administered oxytocin in the first stage of delivery [18]. The oxytocin administration is an important factor that could affect the placental separation time. Therefore, the reason for the differences between the present study and Mejbel and Ali stems from methodological differences.

Essa and Ismail [4] examined the effects of SSC on the health of the mother and the infants and found mean placental separation time was 9 min earlier in the intervention group receiving SSC, compared to the control group. Placental separation occurred within the first 5 min following birth for 96% of the mothers in the intervention group, but only for 0.4% of the mothers in the control group. There was complete placental separation in 100% of the SSC and 80% of the control group, which was a statistically significant difference [4]. In that study placed the infant between the mother’s breasts on mother chest. Thus, breast contact may account for these differences.

Because oxytocin is involved in placental separation, the lack of a statistically significant difference between the mothers in the intervention and control groups with regard to placenta separation duration or status is supported by the oxytocin data.

When 5^th, 15^th and 30^th min pain levels of the mothers in both groups were examined in the present study, the pain levels of the control group were statistically higher than the intervention group (p<0.05) (Table 4). The lower levels of pain in the intervention group were considered to stem from the mothers feeling the baby on their skin as soon as they were born and the mothers being distracted through touching/caressing the babies. Similarly, Hung and Berg [19] reported that a mother receiving SSC was very pleased with the SSC initiative, thus forgetting her pain [19]. Walters et al. [20] reported that the SSC initiative after vaginal birth eases the feeling of pain caused by perineal repair by distracting the mother [20]. In spite of this, Nolan and Lawrence [21] noted that despite the lower pain levels of the mothers in the group receiving immediate SSC than those who did not, the difference was not statistically significant [21]. The difference between the results obtained in those studies could be due to differing settings and the mothers being exposed to different stressors.

Conclusion

SSC between mother and infant significantly decreased the pain level of the mother, but there was no significant difference with regard to placental separation time and oxytocin level when compared to the group not experiencing SSC. In the future, the mother-baby SSC initiative in the third stage of labor should be utilized in different clinical settings with sample groups that have differing characteristics (women who receive/do not receive induction, women who give birth vaginally/through c section, women from regions with different cultural characteristics, etc.). Additionally, SSC should be performed by placing the baby on the mother’s bare breast while the mother is in a supine position and mothers should be encouraged to begin breastfeeding. Beta endorphin and cortisol levels as well as pain levels of mothers, placental separation, and serum oxytocin levels should be evaluated in these settings.