University Of Tasmania

File(s) not publicly available

Within pair association between birth weight and blood pressure at age 8 in twins from a cohort study

journal contribution
posted on 2023-05-16, 11:57 authored by Terry DwyerTerry Dwyer, Christopher BlizzardChristopher Blizzard, Morley, R, Ponsonby, AL
Objectives. To study the association between birth weight and blood pressure in children from multiple pregnancies (multiplets), mostly twins, to determine whether maternal or genetic factors are responsible for the association. Design. Cohort study: Setting. Southern Tasmania. Subjects. 888 children including 104 multiplets (32 monozygotic, 72 dizygotic). Main outcome measure. Systolic blood pressure (mm Hg). Results. Blood pressure decreased with birth weight and increased with current body mass. After adjustment for age and body mass, systolic blood pressure changed by -1.94 mm Hg (95% confidence interval -2.89 to -0.98) per 1 kg increase in birth weight of singletons. For multiplets, blood pressure changed by -7.0 mm Hg (-10.1 to -3.9) for each 1 kg increase in birth weight. This was little altered in within pair analyses (-5.3, -13.8 to 3.2) and was similar for both monozygotic (-6.5, -22.5 to 9.4) and dizvgotic (-4.9, -15.8 to 6.0) pairs. Conclusion. Because the association between birth weight and blood pressure was largely unchanged in within pair analyses, exposures originating in the mother (such as nutritional status) cannot be wholly responsible. The association also remained within monozygotic pairs, suggesting that genetic predisposition is not wholly responsible either. The principal causal pathway must concern mechanisms within the fetoplacental unit. The stronger association in multiplets suggests that factors adversely influencing both blood pressure and birth weight are more prevalent in multiple pregnancies.


Publication title

British Medical Journal










Menzies Institute for Medical Research


British Medical Journal Publishing Group

Place of publication

London, England

Repository Status

  • Restricted

Socio-economic Objectives

Neonatal and child health

Usage metrics