Early vs late-initiated KMC – characteristics of included studies
| S. no | Author, Year | Inclusion criteria | Exclusion criteria | Intervention: early KMC as planned/ as achieved | Control: late KMC as planned/as achieved |
| 1 | WHO iKMC 2021 | All infants with birth weight of 1.0 to 1.799 kg, regardless of gestation, type of delivery, or singleton or twin status (irrespective of clinical stability). | Infants who were unable to breathe spontaneously by 1 hour or who had a major congenital malformation | Immediately after birth; Median initiation time of 1.3 hours after birth | KMC began after the neonate recovered from preterm birth complications and was at least 24 hours old; Median initiation time 53.6 hours after birth |
| 2 | Brotherton 2021 | Birth weight <2000 g and age 1–24 hours | Stable and severely unstable neonates were excluded. Triplets, major congenital malformations, severe jaundice, seizures, and lack of study bed were the other exclusion criteria | KMC initiated <24 hours after admission; Median initiation time 13.6 hours | KMC once stable at >24 hours after admission; Median initiation time 104.5 hours |
| 3 | Mörelius 201524 | Vaginally born singleton preterm infants (32–35 weeks’ gestation) | Infants with congenital malformations and severely unstable infants | Continuous skin-to-skin contact, beginning in the delivery room; Median initiation time not provided | KMC began in the NICU; On day 2, both groups were practicing KMC |
| 4 | Nagai 201025 | Birth weight <2500 g, age <24 hours, no serious malformations, and relatively stable clinical condition | Apnea and intravenous infusion | KMC begun soon as possible, within 24 hours post-birth; Median initiation time 19 hours (IQR 13.00–23.00) | KMC began after complete stabilisation (generally after 24 hours post-birth) Median initiation time 28.5 hours (IQR 25–40) |
KMC, Kangaroo mother care; NICU, neonatal intensive care unit.