Birth weight and blood pressure: cross sectional and longitudinal relations in childhood

Whincup P, Cook D

1995

Guildford and Carlisle, England

The objective was to explore correlations between birth weight and blood pressure in childhood. 1,511 children from 20 primary schools were measured at 9-11 years, including 549 who had been measured at 5-7 years. At 9-11 years birth weight was inversely related to both systolic and diastolic blood pressure once current height and body mass index were taken into account. Placental weight was inversely related to blood pressure but placental ratio (placental weight to birth weight) was unrelated to blood pressure. The main conclusion is that birth weight is the early life factor most importantly related to blood pressure in childhood.

The results of this study are contradicted by the important Jerusalem study (see entry 0075). As in many studies relating an adult condition to birth size, birth order has not been taken into consideration. Yet birth order is the best known single factor influencing birth weight. For example according to a British calculation the average difference in birth weight between first born and second born children is 138 grams. (see Odent M., Tsujino J., Studies exploring health in relation to intrauterine life should look at birth order, BMJ 1997; 314:1416)