Risk and protective factors for child development: An observational South African birth cohort

Abstract

Background

Approximately 250 million (43%) children under the age of 5 years in low- and middle-income countries (LMICs) are failing to meet their developmental potential. Risk factors are recognised to contribute to this loss of human potential. Expanding understanding of the risks that lead to poor outcomes and which protective factors contribute to resilience in children may be critical to improving disparities.

Methods and findings

The Drakenstein Child Health Study is a population-based birth cohort in the Western Cape, South Africa. Pregnant women were enrolled between 20 and 28 weeks’ gestation from two community clinics from 2012 to 2015; sociodemographic and psychosocial data were collected antenatally. Mothers and children were followed through birth until 2 years of age. Developmental assessments were conducted by trained assessors blinded to background, using the Bayley-III Scales of Infant and Toddler Development (BSID-III), validated for use in South Africa, at 24 months of age. The study assessed all available children at 24 months; however, some children were not able to attend, because of loss to follow-up or unavailability of a caregiver or child at the correct age. Of 1,143 live births, 1,002 were in follow-up at 24 months, and a total of 734 children (73%) had developmental assessments, of which 354 (48.2%) were girls. This sample was characterised by low household employment ( n = 183; 24.9%) and household income ( n = 287; 39.1% earning <R1,000 per month), and high prevalence of maternal psychosocial risk factors including alcohol use in pregnancy ( n = 95; 14.5%), smoking ( n = 241; 34.7%), depression ( n = 156; 23.7%), lifetime intimate partner violence ( n = 310; 47.3%), and history of maternal childhood trauma ( n = 228; 34.7%). A high proportion of children were categorised as delayed (defined by scoring < −1 standard deviation below the mean scaled score calculated using the BSID-III norms from a United States population) in different domains (369 [50.5%] cognition, 402 [55.6%] receptive language, 389 [55.4%] expressive language, 169 [23.2%] fine motor, and 267 [38.4%] gross motor). Four hundred five (55.3%) children had >1 domain affected, and 75 (10.2%) had delay in all domains. Bivariate and multivariable analyses revealed several factors that were associated with developmental outcomes. These included protective factors (maternal education, higher birth weight, and socioeconomic status) and risk factors (maternal anaemia in pregnancy, depression or lifetime intimate partner violence, and maternal HIV infection). Boys consistently performed worse than girls (in cognition [β = −0.74; 95% CI −1.46 to −0.03, p = 0.042], receptive language [β = −1.10; 95% CI −1.70 to −0.49, p < 0.001], expressive language [β = −1.65; 95% CI −2.46 to −0.84, p < 0.001], and fine motor [β = −0.70; 95% CI −1.20 to −0.20, p = 0.006] scales). There was evidence that child sex interacted with risk and protective factors including birth weight, maternal anaemia in pregnancy, and socioeconomic factors. Important limitations of the study include attrition of sample from birth to assessment age and missing data in some exposure areas from those assessed.

Conclusions

This study provides reliable developmental data from a sub-Saharan African setting in a well-characterised sample of mother–child dyads. Our findings highlight not only the important protective effects of maternal education, birth weight, and socioeconomic status for developmental outcomes but also sex differences in developmental outcomes and key risk and protective factors for each group.

Abstract

Kirsten Ann Donald and colleagues reveal the protective effects of birth weight, mother's education, and socioeconomic status in a child's development in South Africa.

Author summary

Why was this study done?

• Child development in early childhood lays a foundation for lifelong learning.

• Risk and protective factors for child development are known to include many issues faced by children growing up in low- and middle-income countries.

• Studies indicate a difference between boys and girls in terms of impact of factors influencing development, but these have not been evaluated in a sub-Saharan African context.

What did the researchers do and find?

• We assessed child development at 2 years of 734 children in the Drakenstein Child Health Study, Western Cape, South Africa.

• We assessed potential risk and protective factors identified from prior literature to impact child development.

• We found a number of important risk factors that contributed to poor developmental outcomes in children in this cohort.

What do these findings mean?

• Boys appear to be at higher risk of poor developmental performance in a high-risk environment.

• Key protective factors include mothers having at least some secondary school education, better home circumstances, and healthy birth weight, and key risk factors include maternal anaemia in pregnancy, poor maternal health (such as HIV), and maternal mental health problems.

• Child sex interacts with the associations between key protective and risk factors and developmental outcomes.

• Understanding the related and interacting roles of factors reported in this study may inform integrated intervention policy design and implementation for supporting development in high-risk environments.