Is early childhood development impeded by the birth timing of the younger sibling?

Gursimran Dhamrait; Melissa O'Donnell; Hayley Christian; Gavin Pereira

doi:10.1371/journal.pone.0268325

Is early childhood development impeded by the birth timing of the younger sibling?

PLoS One. 2022 May 10;17(5):e0268325. doi: 10.1371/journal.pone.0268325. eCollection 2022.

Authors

Gursimran Dhamrait^{1

2

3}, Melissa O'Donnell^{1

4}, Hayley Christian^{1

2}, Gavin Pereira^{5

6

7}

Affiliations

¹ Telethon Kids Institute, The University of Western Australia, Perth, Western Australia, Australia.
² School of Population and Global Health, The University of Western Australia, Perth, Western Australia, Australia.
³ School of Health and Society, The University of Wollongong, Wollongong, New South Wales, Australia.
⁴ Australian Centre for Child Protection, University of South Australia, Adelaide, South Australia, Australia.
⁵ Curtin School of Population Health, Curtin University, Perth, Australia.
⁶ Centre for Fertility and Health (CeFH), Norwegian Institute of Public Health, Oslo, Norway.
⁷ enAble Institute, Curtin University, Perth, Western Australia, Australia.

Abstract

Background: This study investigated whether the timing of birth of the younger siblings was associated with the risk of the older siblings' developmental vulnerability in early childhood.

Methods: Linkage of population-level birth registration, hospital, and perinatal datasets to Australian Early Development Census (AEDC) records (2009-2015), enabled follow-up of a cohort of 32,324 Western Australia born singletons. Children with scores <10th percentile on an individual AEDC domain (Physical Health and Wellbeing; Social Competence; Emotional Maturity; Language and Cognitive Skills (school-based); and Communication Skills and General Knowledge) were classified as developmentally vulnerable. Modified Poisson Regression was used to estimate relative risks (RR) for associations between post-birth interpregnancy intervals (IPIs) and developmental vulnerability.

Results: Relative to post-birth IPIs of 18-23 months, post-birth IPIs of <6 and 6-11 months were associated with an increased risk of children being classified as DV1 (aRR 1.21, 95% CI: 1.11-1.31) and DV2 (aRR 1.31, 95% CI: 1.15-1.49); and DV1 (aRR 1.10, 95% CI: 1.03-1.17) and DV2 (aRR 1.21, 95% CI: 1.09-1.34), respectively. Post-birth IPIs of <6 months were associated with an increased risk on four of the five AEDC domains. Post-birth IPIs of 48-60 months were associated with an increased risk of developmental vulnerability; however, the risk was statistically significant for DV1, DV2 and the domains of Emotional Maturity and Language and Cognitive Skills (school-based).

Conclusions: Developmental vulnerability was associated with having a closely spaced younger sibling (<12 months post-birth IPIs). Optimising birth spacing should be further investigated as a potential means for improving child development outcomes.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Australia
Birth Intervals
Child
Child Development*
Child, Preschool
Female
Humans
Pregnancy
Siblings*
Social Skills

Grants and funding

Funding statement’ should read as the following: ‘This work was supported by the Australian Research Council Centre of Excellence for Children and Families over the Life Course [grant number CE140100027]. GD was supported by the ARC Centre of Excellence for Children and Families over the Life Course Scholarship, the ARC Centre of Excellence for Children and Families over the Life Course Top-Up Scholarship and the Stan and Jean Perron Top-Up Scholarship. HC is supported by an Australian National Heart Foundation Future Leader Fellowship [grant number 102549]. MO is supported by a Western Australian Department of Health Merit Award. GP was supported with funding from the National Health and Medical Research Council Project and Investigator Grants [grant numbers GNT1099655 and GNT1173991] and the Research Council of Norway through its Centres of Excellence funding scheme [grant number 262700]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.