Associations Between Fetal Growth and Self-Perceived Health Throughout Adulthood: A Co-twin Control Study

Area of Science:

• Developmental Origins of Health and Disease (DOHaD)
• Behavioral Genetics
• Public Health

Background:

• Low birth weight (LBW) has known long-term health consequences, but its impact on self-perceived health is less understood.
• Existing studies are limited by small sample sizes and focus on pre-adulthood outcomes.
• Heritability of both LBW and self-perceived health complicates disentangling direct effects from shared genetic or environmental influences.

Purpose of the Study:

• To investigate the association between low birth weight (LBW) and self-perceived health in early and later adulthood.
• To utilize a large, genetically informative twin sample to explore these relationships.
• To employ a co-twin control design to assess LBW effects independent of shared genetic and environmental factors.

Main Methods:

• Analysis of a large Swedish twin registry (over 50,000 individuals).
• Examination of self-perceived health in relation to birth weight across adulthood.
• Application of the co-twin control design to isolate individual-specific effects.

Main Results:

• A significant association was found between lower birth weight and poorer self-perceived health in adulthood, albeit with a small effect size.
• Co-twin control analyses indicated that shared underlying liabilities (genetic or environmental) might explain the observed association.
• The findings suggest that the link between LBW and self-perceived health may not be a direct causal effect.

Conclusions:

• While LBW is associated with self-perceived health, the effect appears small and potentially mediated by shared genetic or environmental factors.
• Further research is needed to conclusively determine the direct impact of LBW on self-perceived health.
• The study highlights the complexity of understanding developmental influences on adult health outcomes.