Study title

México

Individual

Study setting and designThis is an observational and comparative study. The sample was selected nonprobabilistically from the neonatal population of hospitals in Mexico City between May 2020 and March 2021. All parents in the study gave their written informed consent after having been informed in detail about the research project. The assessments were observational and nonintrusive to the infants, and the procedures were conducted in agreement with the Declaration of Helsinki.ParticipantsThe study participants eligible for evaluation between 3 and 5 months of age post term were identified between hospital admission and delivery. The inclusion criteria for the exposed and nonexposed groups were singleton births, >36 weeks of gestational, no congenital, chromosomal, or structural abnormalities that became apparent after birth, no serious illness or complications during the pregnancy or delivery (such as perinatal asphyxia) and no need for intensive care for the mother or newborn. For both groups, the exclusion criteria were infant birthweight < the 3rd percentile at birth; parental history of psychiatric illnesses and/or psychoactive substance use as verified in the medical record; failure to complete the assessments; or parental withdrawal from the study. The infants in the exposed group were born to mothers without any vaccinations who were RT–PCR-SARS-CoV2 positive (during the time between hospital admission and delivery) in one test. The infants in the nonexposed group were born to mothers who, upon entering the hospital to give birth, were not suspected of having COVID-19 because they had no symptoms or history of contact with someone positive for SAR-CoV-2 or with COVID-19 symptoms. All the recruited mothers in this study were assessed for their risk of suffering from COVID-19 as part of the institutional strategy during the onset of the pandemic. If the mother had a high risk of suffering COVID-19, RT–PCR-SARS-CoV2 tests were performed for the mother and her newborn, and they were moved to an isolated ward. Then, if neither was at risk of loss of life, they were removed from the isolation ward and subsequently discharged.Personal data of parents and newbornsThe demographic data of the parents and newborns, as well as the maternal–neonatal medical history during pregnancy, were obtained from the hospital records. Data on the following demographic and clinical characteristics of newborns were collected: sex, type of birth, gestational age, weight, height and head circumference at birth and medical history. The data of the mothers included age, marital status, educational level, and medical history.Early motor repertoire assessmentThe early motor repertoire was evaluated according to Prechtl’s method by detailed early repertoire assessment that calculated a MOS-R value for 3- to 5-month-old infants. The parents who consented to the study were asked to videotape their infants' spontaneous movements for 3–5 minutes when their children reached between 3 and 5 months of corrected age (CA), which was calculated as conceptional age + weeks of life in compliance with the procedure described by Einspieler et al. (1997). Infants were fully awake and were not crying, fussing, or sucking on a pacifier; their arms and legs were bare, and they could move their limbs and trunks freely. The infants were in the supine position on a mattress, lightly and comfortably dressed and in a silent room without any intervention by the person who was recording. The video was sent by the parents and reviewed by two certified experienced pediatric physiotherapists with GM Trust certified as an advanced scorer. In case of disagreement on an infant’s assessment, they reviewed that infant video to reach a consensus on the final score. If the video did not meet all these requirements, the parents were asked to make the recording again.From these videos, detailed early motor repertoires were evaluated through the following indicators: 1) fidgety movements, which were labeled normal, abnormal, or absent; 2) the concurrent repertoire motor, namely, movements and postures that were apparent at 3–5 months; 3) the total MOS, based on the sum of all instrument values, which ranges from 5 (poor) to 28 points (optimal) [27]; and 4) performance level, which was defined in the literature by two cutoff scores for nonoptimal performance <24 points [3] and for severely reduced performance <14 points. The MOS-R was calculated according to five aspects of motor development: 1) fidgety movements, 2) movement patterns, 3) age adequacy of movement repertoire, 4) postural patterns, and 5) movement character; the aspect of fidgety movements had a maximum score of 12 points, while the other four aspects had maximum scores of 4 points Finally, a phone call was made to explain the results obtained from the evaluation of the videos. The mothers of infants who scored low in the evaluation were advised to attend centers where they could monitor the neurodevelopment of their infants.