A comparison of the merits of using birth weight, or appropriateness of birth weight to gestational age, in the assessment of subsequent growth in twin children

Abstract

Analysis of data relating BW-SDS to subsequent growth shows no significant difference to those groups using BW alone.

Heritability of Head Size in Dutch and Australian Twin Families at Ages 0–50 Years

“…The question remains what the effects of common environment have influenced early age head circumference in the current results. Although pregnancy duration is significantly shorter in twin births (Buckler & Green, 1994;Green & Buckler, 2008), adding it as a covariate did not change the results. Other prenatal factors the may have influenced both twins' head size may lie in the mother's behavior during pregnancy.…”

“…These results suggest that individual differences in head circumference are not only a highly genetic trait from cradle to grave, but also genetically highly stable. The common environmental effect that existed at birth disappeared very early in life (at 4 months), and does not seem to be related to pregnancy duration -an otherwise prominent factor in twin births (Green and Buckler, 2008). Therefore, the current results bode well for future gene hunting studies, such as genome wide association.…”

“…Many pre-and perinatal factors may influence head circumference at birth. Gestational age is perhaps the largest factor in determining birth weight and head circumference (Buckler & Green, 1994;Green & Buckler, 2008). Whether these effects fully disappear after the catch-up growth of preterm infants (Euser et al, 2008;Estourgie-van Burk et al, 2009) is unknown.…”