Abstract: We included 46 trials with 3850 women and their infants; 38 trials with 3472 women and infants contributed data to our analyses. Trials took place in 21 countries, and most recruited small samples (just 12 trials randomized more than 100 women). Eight trials included women who had SSC after cesarean birth. All infants recruited to trials were healthy, and the majority were full term. Six trials studied late preterm infants (greater than 35 weeks' gestation). No included trial met all criteria for good quality with respect to methodology and reporting; no trial was successfully blinded, and all analyses were imprecise due to small sample size. Many analyses had statistical heterogeneity due to considerable differences between SSC and standard care control groups. Results for women SSC women were more likely than women with standard contact to be breastfeeding at one to four months post birth, though there was some uncertainty in this estimate due to risks of bias in included trials (average risk ratio (RR) 1.24, 95% confidence interval (CI) 1.07 to 1.43; participants = 887; studies = 14; I² = 41%; GRADE: moderate quality). SSC women also breast fed their infants longer, though data were limited (mean difference (MD) 64 days, 95% CI 37.96 to 89.50; participants = 264; studies = six; GRADE:low quality); this result was from a sensitivity analysis excluding one trial contributing all of the heterogeneity in the primary analysis. SSC women were probably more likely to exclusively breast feed from hospital discharge to one month post birth and from six weeks to six months post birth, though both analyses had substantial heterogeneity (from discharge average RR 1.30, 95% CI 1.12 to 1.49; participants = 711; studies = six; I² = 44%; GRADE: moderate quality; from six weeks average RR 1.50, 95% CI 1.18 to 1.90; participants = 640; studies = seven; I² = 62%; GRADE: moderate quality). Women in the SCC group had higher mean scores for breastfeeding effectiveness, with moderate heterogeneity (IBFAT (Infant Breastfeeding Assessment Tool) score MD 2.28, 95% CI 1.41 to 3.15; participants = 384; studies = four; I² = 41%). SSC infants were more likely to breast feed successfully during their first feed, with high heterogeneity (average RR 1.32, 95% CI 1.04 to 1.67; participants = 575; studies = five; I² = 85%). Results for infants SSC infants had higher SCRIP (stability of the cardio-respiratory system) scores overall, suggesting better stabilization on three physiological parameters. However, there were few infants, and the clinical significance of the test was unclear because trialists reported averages of multiple time points (standardized mean difference (SMD) 1.24, 95% CI 0.76 to 1.72; participants = 81; studies = two; GRADE low quality). SSC infants had higher blood glucose levels (MD 10.49, 95% CI 8.39 to 12.59; participants = 144; studies = three; GRADE: low quality), but similar temperature to infants in standard care (MD 0.30 degree Celcius (°C) 95% CI 0.13 °C to 0.47 °C; participants = 558; studies = six; I² = 88%; GRADE: low quality). Women and infants after cesarean birth Women practicing SSC after cesarean birth were probably more likely to breast feed one to four months post birth and to breast feed successfully (IBFAT score), but analyses were based on just two trials and few women. Evidence was insufficient to determine whether SSC could improve breastfeeding at other times after cesarean. Single trials contributed to infant respiratory rate, maternal pain and maternal state anxiety with no power to detect group differences. Subgroups We found no differences for any outcome when we compared times of initiation (immediate less than 10 minutes post birth versus early 10 minutes or more post birth) or lengths of contact time (60 minutes or less contact versus more than 60 minutes contact). Evidence supports the use of SSC to promote breastfeeding. Studies with larger sample sizes are necessary to confirm physiological benefit for infants during transition to extra-uterine life and to establish possible dose-response effects and optimal initiation time. Methodological quality of trials remains problematic, and small trials reporting different outcomes with different scales and limited data limit our confidence in the benefits of SSC for infants. Our review included only healthy infants, which limits the range of physiological parameters observed and makes their interpretation difficult.

Plain-language summary: We searched for randomized controlled studies of immediate and early SSC on 17 December 2015. We found thirty-eight studies with 3472 women that provided data for analysis. Most studies compared early SSC with standard hospital care for women with healthy full-term babies. In eight studies women gave birth by cesarean, and in six studies the babies were healthy but born preterm at 35 weeks or more. More women who had SSC with their babies were still breastfeeding at one to four months after giving birth (14 studies, 887 women, moderate-quality evidence). Mothers who had SSC breast fed their infants longer, too, on average over 60 days longer (six studies, 264 women, low-quality evidence). Babies held in SSC were more likely to have breast fed successfully during their first breast feed (five studies, 575 women). Babies held in SSC had higher blood glucose levels (three studies, 144 women, low-quality evidence), but similar temperature to babies with standard care (six studies, 558 women, low-quality evidence). We had too few babies in our included studies and the quality of the evidence was too low for us to be very confident in the results for infants. Women giving birth by cesarean may benefit from early SSC, with more women breastfeeding successfully and still breastfeeding at one to four months (fourteen studies, 887 women, moderate-quality evidence), but there were not enough women studied for us to be confident in this result. We found no clear benefit to immediate SSC rather than SSC after the baby had been washed and examined. Neither did we find any clear advantage of a longer duration of SSC (more than one hour) compared with less than one hour. Future trials with more women and infants may help us answer these questions with confidence. SSC was defined in various ways and different scales and times were used to measure different outcomes. Women and staff knew they were being studied, and women in the standard care groups had varying levels of breastfeeding support. These differences lead to wide variation in the findings and a lower quality evidence. Many studies were small with less than 100 women participating. The evidence from this updated review supports using immediate or early SSC to promote breastfeeding. This is important because we know breastfeeding helps babies avoid illness and stay healthy. Women giving birth by cesarean may benefit from early SSC but we need more studies to confirm this. We still do not know whether early SSC for healthy infants helps them make the transition to the outside world more smoothly after birth, but future good quality studies may improve our understanding. Despite our concerns about the quality of the studies, and since we found no evidence of harm in any included studies, we conclude the evidence supports that early SSC should be normal practice for healthy newborns including those born by cesarean and babies born early at 35 weeks or more.