“…The periodicity of interventions was weekly in six studies (Ammerman et al, 2022;Barone et al, 2020;Berlin et al, 2018;Harden et al, 2021;Hepworth et al, 2020;Pasalich et al, 2019) and monthly in four studies (Alvarenga et al, 2019;Alvarenga et al, 2021;Chung et al, 2018;Kristensen et al, 2020). The remaining studies had a variable periodicity during the program, such as weekly-biweekly-monthly during 24 months of the infants' age (Alarcão et al, 2021;Conti et al, 2021); weekly-biweekly-monthly from pregnancy to six months of postpartum (Christodoulou et al, 2019;Tomlinson et al, 2020); weekly-monthly from six days to four months (Vargas-Porras et al, 2021); every two-to-three weeks during nine months (Firk et al, 2020); and one session two days after birth, one session one week after birth, and another session four weeks later (Høifødt et al, 2020).…”