1. Objectives
To assess the effects of immediate or early skin-to-skin contact (SSC) for healthy newborn infants compared to standard contact on breastfeeding, infant physiology, and maternal-infant bonding
2. How studies were identified
The following databases were searched in December 2015:
- Cochrane Pregnancy and Childbirth Group’s Trials Register
- CENTRAL (The Cochrane Library 2015)
- MEDLINE
- EMBASE
- CINAHL
Relevant reference lists, journals and conference proceedings were searched. Contact was also made with authors and groups in the field, including the International Network for Kangaroo Mother Care
3. Criteria for including studies in the review
3.1 Study type
Randomized controlled trials, including cluster-randomized controlled trials
3.2 Study participants
Mothers and healthy full term (≥37 weeks’ gestation) or late preterm (34 to <37 weeks’ gestation) infants receiving SSC within 24 hours of birth, and controls undergoing standard care
(Infants weighing ≤1500 g were excluded as it was considered unlikely that they had completed 33 weeks’ gestation)
3.3 Interventions
SSC was compared with standard contact. Two subcategories of SSC were considered:
- ‘Immediate, Birth, or Very Early SSC’, in which the infant was placed skin-to-skin on the mother’s chest within 10 minutes of birth
- ‘Early SSC’, which was defined as SSC between 10 minutes and 24 hours of birth
In both subcategories of SSC, the baby was kept dry and warm with a blanket or the mother’s gown covering the baby’s back, and the infant may have worn a diaper or cap. The most important feature was direct, ventral-to-ventral SSC. Standard contact involved infants being held swaddled or dressed in their mother’s arms or placed in open cribs or under radiant warmers in the mother’s room or elsewhere
3.4 Primary outcomes
Breastfeeding outcomes
- Number of mothers breastfeeding (any breastfeeding) one month to four months post-birth
- Duration of breastfeeding
Infant outcomes
- Infant physiological stabilization, as measured by the SCRIP score (ranges from zero to six; assesses the stability of the cardio-respiratory system including heart rate, respiratory rate and arterial haemoglobin oxygen saturation [SaO2])
- Blood glucose levels during/after SSC
- Infant thermoregulation, as indicated by axillary temperature changes during/after SSC
3.5 Secondary outcomes
Breastfeeding outcomes
- Breastfeeding rates/exclusivity (assessed using the Index of Breastfeeding Status) at hospital discharge and up to six months post-birth
- Effective breastfeeding (assessed using the Infant Breastfeeding Assessment Tool [IBFAT], which rates infant suckling competence)
- Breast temperature during and after SSC and breast engorgement three days post-birth
Infant outcomes
- Heart rate and respiratory status during and after SSC
- Admission to neonatal intensive care unit
- Rate of growth in weight (gm/kg/day)
- Length of hospital stay
- Duration of crying
Maternal outcomes
- Perceptions of bonding to infant (assessed using the Parent-Child Early Relational Assessment [PCERA])
- Post-caesarean pain
- Sensitivity to infant cues (assessed using PCERA)
- Anxiety (assessed using the State Trait Anxiety Inventory)
- Parenting confidence (assessed using the Parenting Sense of Competence Scale)
4. Main results
4.1 Included studies
Forty-six randomized controlled trials enrolling 3850 mother-infant dyads were identified, although eight trials involving 378 mother-infant pairs did not contribute data for analysis
- Forty studies included only healthy term infants, five studies enrolled healthy late preterm infants, and one trial enrolled both healthy term and late preterm infants
- SSC was initiated from 0 minutes post-birth to 21.3 hours post-birth, with 18 of the 38 trials contributing data beginning SSC immediately after birth. The duration of SSC ranged from 15 minutes to 37 hours
- Control infants had variable separation from mothers, ranging from removal from mothers for 12 to 24 hours post-birth (8 trials) to being swaddled and held soon after birth (5 trials)
4.2 Study settings
- Canada, Chile, Germany (2 trials), Guatemala (4 trials), India (4 trials), Iran (5 trials), Israel, Italy, Japan, Nepal, Pakistan, Poland, Russian Federation, South Africa, Spain (3 trials), Sweden (2 trials), Thailand, the United Kingdom of Great Britain and Northern Ireland (2 trials), the United States of America (9 trials), Viet Nam, and Taiwan, China (3 trials)
4.3 Study settings
How the data were analysed
Four comparisons were made: i) immediate or early SSC versus standard care; ii) SSC versus standard contact after caesarean birth; iii) SSC versus standard contact by time of initiation; and iv) SSC versus standard contact by dose (length of contact time). Data were pooled using fixed effect meta-analysis. Where substantial clinical or statistical heterogeneity was detected (I²>40%) random effects meta-analysis was used. Mean differences (MD) or standardized mean differences (SMD) and 95% confidence intervals (CI) were generated for continuous data, and risk ratios (RR) and corresponding 95% CI were produced for dichotomous data. Cluster-randomized trials were adjusted for clustering using intra-class correlation coefficients. To explore potential sources of heterogeneity, the following subgroup analyses were conducted for primary outcomes:
- Initiation of SSC in comparison three: immediate (<10 minutes from birth) versus delayed (≥10 minutes after birth)
- Dose of SSC in comparison four: high (>60 minutes in the first 24 hours) versus low (≤60 minutes)
Sensitivity analyses were also planned to explore the effect of methodological quality on primary outcomes; however, all identified studies failed to meet the criteria for low risk of bias. High levels of heterogeneity were investigated in sensitivity analyses by excluding single studies that accounted for much of the variation
Results
Immediate or early skin-to-skin contact versus standard care
Breastfeeding rates/duration
In 14 studies including 887 mother-infant pairs, a greater number of SSC infants were still breastfed (any breastfeeding) at one to four months post-birth (RR 1.24, 95% CI [1.07 to 1.43], p=0.0046; I²=41%). Six of seven studies reporting on the duration of breastfeeding in days favoured SSC, but this did not reach statistical significance in meta-analysis (MD 42.55 days, 95% CI [-1.69 to 86.79], p=0.059; I²=66%; 7 studies/324 infants).
Physiological stability
In two studies involving 81 infants, a higher mean SCRIP score in the first six hours post-birth, indicating better physiological stabilization, was observed in the SSC intervention group (SMD 1.24 points, 95% CI [0.76 to 1.72], p<0.00001; I²=0%).
Blood glucose
In three studies including 144 infants, blood glucose 75 to 180 minutes post-birth was higher in the SSC group compared to the control group, with an MD of 10.49 mg/dL (95% CI [8.39 mg/dL to 12.59 mg/dL], p<0.00001; I²=0%).
Thermoregulation
Axillary temperature 90 minutes to 2.5 hours post-birth was 0.3 degrees centigrade higher among the group receiving SSC (MD 0.30°C, 95% CI [0.13 to 0.47], 6 trials/558 infants; I²=88%).
Breastfeeding secondary outcomes
A 30% increase in the rate of exclusive breastfeeding from discharge to one month post-birth was observed among the intervention group (RR 1.30, 95% CI [1.12 to 1.49], 6 trials/711 infants; I²=44%). The rate of exclusive breastfeeding remained significantly higher among the SSC group from six weeks to six months post-birth (RR 1.50, 95% CI [1.18 to 1.90], 7 trials/640 infants; I²=62%). However, in three studies including 245 women in which breastfeeding status at day 28 to one month post-birth was reported using the Index of Breastfeeding Status, there was no significant difference between intervention and control groups. Breastfeeding at one year post-birth was also not different between groups. Breastfeeding effectiveness, assessed by the IBFAT score of suckling competence, was significantly higher with SSC in pooled analysis of four studies (MD in IBFAT scores 2.28, 95% CI [1.41 to 3.15], 384 dyads; I²=41%). Using a modified IBFAT score, breastfeeding effectiveness was significantly higher with SSC in five studies including 575 mother-infant pairs (RR 1.32, 95% CI [1.04 to 1.67], I²=85%). There was no difference between groups in the number of infants suckling at two hours post-birth in a single study of 88 dyads. In the same study, mean variation in breast temperature 30 to 120 minutes post-birth was significantly greater in the SSC group (MD 0.60, 95% CI [0.34 to 0.86], p<0.00001; 132 participants). Breast engorgement pain at three days post-birth was significantly less in SSC groups in two studies involving 131 women (SMD -0.41, 95% CI [-0.76 to -0.06], p=0.020; I²=8%).
Infant secondary outcomes
No statistically significant differences were observed for respiratory rate (four studies) or heart rate (three studies) between SSC and control groups. In one study comparing five physiological parameters for stability requiring medical attention (infant skin temperature, heart rate, oxygen saturation, blood glucose and fraction of inspired oxygen), a greater number of SSC infants did not exceed parameters (RR 10.83, 95% CI [1.63 to 72.02], p=0.014; 31 dyads). Admission to a neonatal intensive care unit did not differ between groups, and length of hospital stay in late preterm infants also did not differ. No significant difference was observed between groups in pooled analysis of infant body weight change 14 days post-birth (2 trials/43 infants). A greater number of SSC-exposed infants were found to cry no more than one minute during 90 minutes’ observation (RR 12.86, 95% CI [1.91 to 86.44], p=0.0086; 1 trial/29 dyads) and cried for a shorter length of time during 75 minutes’ observation (MD -8.01 minutes, 95% CI [-8.98 to -7.04], p<0.00001; 1 trial/44 dyads).
Maternal secondary outcomes
In meta-analysis of three studies involving 439 women, mothers in the SSC group exhibited a strong preference for the same type of post-delivery care in the future (RR 6.04, 95% CI [2.05 to 17.83], I²=85%). Using PCERA, in one study of 61 women no difference in maternal positive affective involvement was found between groups at 12 months post-birth. However, SSC dyads were more mutual and reciprocal (MD 1.30, 95% CI [0.24 to 2.36], p=0.017; 1 trial/61 women). Mothers in the SSC group displayed less state anxiety day three post-birth in pooled analysis of three trials involving 390 women (SMD -0.32, 95% CI [-0.59 to -0.04], I²=31%). No statistically significant differences were observed between groups for the outcome parenting confidence.
Skin-to-skin contact versus standard contact after caesarean birth
Breastfeeding rates/duration
Rates of exclusive breastfeeding were not different between intervention and control groups at hospital discharge to one month post-caesarean birth (RR 1.00, 95% CI [0.53 to 1.88], 1 trial/34 participants), or at six weeks to six months post-caesarean birth (RR 1.16, 95% CI [0.95 to 1.43], 2 trials/144 participants). Rates of any breastfeeding were significantly higher in the SSC group at one to four months post-caesarean birth in pooled analysis of two trials involving 220 mother-infant pairs (RR 1.22, 95% CI [1.04 to 1.44]).
Secondary outcomes
Success of the first breastfeeding episode was significantly higher in the group receiving SSC (MD 1.37 IFBAT score, 95% CI [0.12 to 2.62], 2 trials/124 infants; I²=0%). Infant respiratory rate 75 minutes to two hours post-caesarean birth, maternal post-caesarean pain at four hours, and maternal state anxiety eight hours to three days post-caesarean birth were not different between intervention and control groups.
Skin-to-skin contact versus standard contact by time of initiation
In subgroup analyses comparing SSC initiated <10 minutes post-birth to SSC initiated ≥10 minutes post-birth, no meaningful differences in results were found for the primary outcomes breastfeeding one month to four months post-birth, duration of breastfeeding, SCRIP score in the first six hours post-birth, or infant blood glucose 75 to 90 minutes post-birth. Infant axillary temperature was statistically significantly higher than controls in the ≥10 minutes post-birth SSC group (MD 0.23 degrees centigrade, 95% CI [0.18 to 0.28], p<0.00001; 2 trials/240 infants), but not in the <10 minutes post-birth SSC group (MD 0.11 degrees centigrade, 95% CI [-0.00 to 0.22], p=0.053; 3 trials/168 infants). No other analyses were conducted.
Skin-to-skin contact versus standard contact by dose (length of contact time)
In subgroup analyses comparing low-dose SSC (≤60 minutes) to high-dose SSC (>60 minutes), no meaningful differences in results were found for the primary outcomes breastfeeding one month to four months post-birth or duration of breastfeeding. No other comparisons between low- and high dose SSC were conducted.
5. Additional author observations*
None of the included studies were blinded and most trials contributing data were at unclear risk of allocation concealment bias. GRADE quality of evidence assessment rated evidence for the outcomes breastfeeding one month to four months post-birth, exclusive breastfeeding at hospital discharge, and exclusive breastfeeding six weeks to six months post-discharge as moderate quality. Evidence for the outcomes duration of breastfeeding, SCRIP score in the first six hours post-birth, infant blood glucose 75 to 180 minutes post-birth, and infant axillary temperature 90 minutes to 2.5 hours post-birth was rated as low quality.
The evidence presented in this review supports the use of SSC for improving breastfeeding outcomes, although inadequate evidence was found to make recommendations with respect to details such as timing of initiation and dose. The findings are in general agreement with results from other studies as well as the recommendation for SSC by the UNICEF endorsed Baby Friendly Hospital Initiative. A clinically meaningful increase in infant blood glucose post-birth was found with SSC, and cardio-respiratory stability was also improved, although further studies are needed to confirm these findings.
Given the overall low to moderate quality of evidence and the lack of ability to determine whether a differential effect by timing or dose of SSC exists, further trials examining the effects of SSC by timing of initiation and duration are required.
