Papers

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

^a University Department of Public Health, Royal Free Hospital School of Medicine, London NW3 2PF, ^b Department of Public Health Sciences, St George's Hospital Medical School, London SW17 0RE

Correspondence to: Dr Whincup.

Abstract

Objective: To examine cross sectional and longitudinal relations between birth weight and blood pressure in childhood.
Design: Cross sectional study of primary school children aged 9-11 years, with analysis in relation to previous measurements at 5-7 years in a subgroup.
Setting: 20 primary schools in Guildford and Carlisle.
Subjects: 1511 children measured at 9-11 years (response rate 79%), including 549 who had been measured at 5-7 years.
Main outcome measures: Blood pressure at 9-11 years, change in blood pressure between 5-7 and 9-11 years, birth weight (based on maternal recall), and placental weight (based on birth records).
Results: At 9-11 years birth weight was inversely related both to systolic blood pressure (regression coefficient -2.80 mm Hg/kg; 95% confidence interval -3.84 to -1.76) and to diastolic blood pressure (regression coefficient -1.42 mm Hg/kg; -2.14 to -0.70) once current height and body mass index were taken into account. Placental weight was inversely related to blood pressure after adjustment for current height and body mass index but placental ratio (placental weight to birth weight) was unrelated to blood pressure. Between 5-7 and 9-11 years systolic blood pressure rose more rapidly in children of lower birth weight (regression coefficient -1.71 mm Hg/kg; -3.35 to -0.07). This effect seemed to be stronger in girls.
Conclusions: Birth weight rather than placental ratio is the early life factor most importantly related to blood pressure in childhood. The results support the possibility of "amplification" of the relation between birth weight and blood pressure, particularly in girls.

Introduction

Barker and colleagues argued that early life factors, acting particularly in utero, may have a strong influence on subsequent cardiovascular risk.¹ An inverse relation between birth weight and subsequent blood pressure (lower birth weight being associated with higher subsequent mean blood pressure) has been reported in adults^{2 3 4} and children,^{2 5 6 7 8} though not consistently in adolescents.^{9 10 11} Earlier reports also suggested that a large placenta, particularly in the presence of low birth weight, was related to subsequent high blood pressure and the risk of hypertension.³ Recent reports have suggested that the birth weight and blood pressure relation becomes stronger with age ("amplification")¹² and that this may be an example of "programming."¹³ However, the evidence for amplification is based almost entirely on comparison of cross sectional studies with subjects of different ages and times of birth rather than on longitudinal measurements.¹⁴

We studied the relation between birth weight and blood pressure in children. In cross sectional analyses at 9-11 years of age we examined the relations between birth weight and blood pressure and the influence of placental weight. In longitudinal analyses based on children measured at both 5-7 and 9-11 years of age we examined the development of the birth weight and blood pressure relation with age.

Subjects and methods

We present data based on two surveys four years apart (1987 and 1991) in Guildford and Carlisle. The sampling and methods used have been detailed elsewhere.^{6 15 16} Both surveys were carried out in the same sample of 10 primary schools in each town. The second survey included all children from the earlier survey still attending the schools together with similar numbers of children in the same classes. In both surveys measurements were made by a team of trained nurse observers, who visited schools in the two areas in sequence.

Blood pressure was measured after five minutes' rest with the child seated and the arm supported at chest level. Three blood pressure measurements were made one minute apart on the right arm with the Dinamap 1846SX oscillometric blood pressure recorder (Critikon Inc, United States).¹⁷ All analyses were based on the means of the three readings. At 9-11 years all measurements were made with the adult size cuff (cuff bladder 22 cm x 12 cm); at 5-7 years all measurements were standardised to the child size cuff (cuff bladder 15 cm x 9 cm), as described.¹⁸ These cuff sizes ensured that the minimum cuff bladder width to arm circumference ratio of 40% recommended by the American Heart Association¹⁹ was met for 98% of the study population at age 9-11 years and for 99% of the population at age 5-7 years. Ethnic group was assessed on the basis of the child's appearance.

A self administered parental questionnaire sent to the parents on the day of examination in the 1991 survey was used to collect information on birth weight and gestational age (assessed on the basis of recall of the number of weeks the birth was early or late). With the permission of mothers, hospital birth record information was collected on subjects born in the two study areas, including birth weight, gestational age based on date of last menstrual period, and (available in Carlisle only) placental weight. Because there was close agreement in birth weight and gestational age between maternal recall and birth record information, analyses of birth weight and blood pressure at 9-11 years were based on maternal recall data.

A total of 924 children aged 5-7 years (84% response rate) took part in the 1987 survey; 1511 children aged 9-11 years (79% response rate) took part in the 1991 survey. All but eight children were of European origin; exclusion of the others had no effect on the results. Among the 1511 children measured in 1991, questionnaires with full birth details were returned for 1230 (81%). Of these, 996 children were born in the study towns; maternal consent to retrieval of birth records was obtained for 995 children. Complete birth records were obtained for 838 (84%) of these children, 473 of whom were Carlisle subjects with data on placental weight. The 1991 survey included 549 children of 699 (79%) who took part in the 1987 survey and were still attending the survey schools. The longitudinal relations between birth weight and blood pressure were examined in 523 of these 549 subjects for whom maternal recall information on birth weight was available.

Statistical analysis--All analyses were carried out with the statistical analysis software (SAS) package.²⁰ Birth weight, placental weight, age, and measures of current body size--height and body mass index (weight (kg) divided by height (m²)--were either treated as continuous variables or ranked and grouped in equal thirds or fifths. Standard linear regression techniques were used throughout and all analyses standardised for the effect of study area. Changes in blood pressure between 5-7 and 9-11 years were examined both as absolute changes and as changes in rank by using standard deviation scores. These were calculated separately for blood pressure at 5-7 years and 9-11 years, standardised for age, sex, height, and body mass index at each age. Changes in standard deviation scores were then regressed on birth weight to examine the relation between birth weight and change in blood pressure rank between 5-7 and 9-11 years.

Results

BIRTH WEIGHT AND CURRENT BODY SIZE (AGE 9-11)

Birth weight showed little or no relation with blood pressure in a model adjusted only for age and sex (fig 1). However, after additional adjustment for height and body mass index (correlation coefficients with birth weight r=0.19, r=0.10 respectively) birth weight showed a smooth graded inverse relation with both systolic and diastolic pressure (fig 1). The corresponding regression coefficients defining the increase in blood pressure for a 1 kg fall in birth weight were -2.80 mm Hg (95% confidence interval -3.84 to -1.76; P<0.0001) for systolic pressure and -1.42 mm Hg (-2.14 to -0.70; P<0.0001) for diastolic pressure. The relations between birth weight and blood pressure were very similar in preterm and term infants, in boys and girls, and in children in the top and bottom thirds of the distribution of height and body mass index. They were also independent of parity, social class, maternal blood pressure, and maternal smoking in pregnancy.

View larger version (19K): [in this window] [in a new window]   FIG 1--Birth weight and blood pressure at 9-11 years, showing effect of adjustment for current body size. Mean blood pressures and 95% confidence intervals (bars) are shown for each fifth of birth weight. *----* Adjusted for age and sex only. O----O Adjusted for age, sex, height, and body mass index

BIRTH WEIGHT AND PLACENTAL WEIGHT (AGE 9-11)

Relations between birth weight, placental weight, and blood pressure were examined in 473 Carlisle children with data on these variables. Placental weight was strongly correlated with birth weight (r=0.45). Like birth weight, it showed a smooth inverse relation with blood pressure, particularly systolic pressure, once current height and body mass index were taken into account. For a 100 g fall in placental weight systolic pressure rose by -0.84 mm Hg (95% confidence interval -1.50 to -0.18; P=0.012). However, including birth weight in the regression model greatly attenuated the relation between placental weight and blood pressure. Moreover, the placental ratio (placental weight to birth weight) showed no relation either with systolic pressure (P=0.89) or with diastolic pressure (P=0.37).

When the mean systolic blood pressure for each third of placental weight and birth weight was examined (table I) the highest mean blood pressure was observed in the group in the lowest third of both birth weight and placental weight distributions; subjects with low birth weight and high placental weight did not have a particularly high mean blood pressure. Similar findings were recorded for diastolic pressure (data not shown). There was no evidence of interaction between birth weight and placental weight, either for systolic (P=0.56) or diastolic (P=0.70) blood pressure. These results were unaffected by exclusion of preterm births (</= 36 weeks).

TABLE I--Birth weight (thirds), placental weight (thirds), and systolic blood pressure (mm Hg) at 9-11
years. Figures are means (SE)
----------------------------------------------------------------------------------------------------------------
                                                         Birth weight (thirds)
----------------------------------------------------------------------------------------------------------------
                                      Low                Mid                  High
Placental weight (thirds)         (</=3120 g)       (3121-3609 g)         (>/=3610 g)              All
----------------------------------------------------------------------------------------------------------------
Low (</=589 g)                   109.4 (1.5)          106.5 (1.7)        106.8 (2.3)+           108.6 (0.8)
Mid (590-689 g)                  108.8 (2.0)          103.4 (1.3)        106.0 (1.4)            105.6 (0.8)
High (>/=690 g)                  103.9 (3.2)+         105.4 (1.7)        105.9 (1.2)            105.3 (0.8)
All                              108.9 (0.8)          106.1 (0.8)        104.2 (0.8)            106.5 (0.6)
----------------------------------------------------------------------------------------------------------------
Analyses were based on 473 Carlisle subjects with complete birth record data and were standardised for age, sex,
height, and body mass index throughout.
+Based on fewer than 20 subjects.

CHANGES BETWEEN 5-7 AND 9-11 YEARS

The relative strengths of the birth weight and blood pressure relation at 5-7 and 9-11 years, standardised for age, sex, height, and body mass index at each age, were examined in 523 children studied longitudinally and in whom birth weight data were available (table II). The regression coefficients, defining the difference in blood pressure for a 1 kg increase in birth weight, increased between 5-7 years and 9-11 years by 73% for systolic pressure and 22% for diastolic pressure. The corresponding within subject analysis taking into account age, sex, height, and body mass index at both ages showed that the increase in the strength of the systolic relation was significant whereas that for diastolic pressure was not. The increase in the strength of the systolic relation appeared to be more pronounced in girls (regression coefficient -3.42 (SE 1.13) mm Hg/kg) than in boys (regression coefficient 0.03 (1.13) mm Hg/kg) (test for interaction, P=0.03).

TABLE II--Birth weight, blood pressure, and change in blood pressure in children measured at 5-7 and 9-11
years
--------------------------------------------------------------------------------------------------------------------
                                                        Systolic                             Diastolic
--------------------------------------------------------------------------------------------------------------------
                                              Regression coefficient               Regression coefficient
                                                      (SE)               P                 (SE)             P
--------------------------------------------------------------------------------------------------------------------
                                             Birth weight and blood pressure+
Age 9-11 years                                      -3.95 (0.87)        <0.0001         -1.34 (0.66)       0.03
Age 5-7 years                                       -2.28 (0.66)         0.0006         -1.10 (0.51)       0.03
                      Birth weight and change in blood pressture between 5-7 years and 9-11 years++
Absolute blood pressure change                      -1.71 (0.82)         0.04           -0.08 (0.60)       0.89
Change in blood pressure rank (standard             -0.09 (0.09)         0.28           -0.02 (0.09)       0.83
 normal deviate)
--------------------------------------------------------------------------------------------------------------------
+Regression coefficients (mm Hg/kg) show difference in blood pressure for 1 kg increase in birth weight at each age.
++Regression coefficients show absolute change in blood pressure (mm Hg) and change in blood pressure rank
(expressed as standard normal deviate) between 5-7 and 9-11 years for 1 kg increase in birth weight.
All analyses were based on 523 subjects followed up between 5-7 and 9-11 years with maternal recall data on birth
weight and were standardised for area, age, sex, height, and body mass index at each age.

The extent to which birth weight was related to change in blood pressure rank between 5-7 and 9-11 years was examined by determining the standard normal deviate of blood pressure in each subject at 5-7 and 9-11 years separately (taking into account age, sex, height, and body mass index at each age) and studying the relation between birth weight and change in standard normal deviate (table II). Overall, birth weight had little or no relation to change in the rank of blood pressure between these ages. However, birth weight seemed to be inversely related to a change in blood pressure rank in girls (regression coefficient -0.26 (SE 0.12)) rather than in boys (regression coefficient 0.09 (0.12)) (test for interaction, P=0.05).

Discussion

The inverse relation between birth weight and blood pressure after standardisation for current body size was consistent with the findings of earlier studies in children.^{2 5 6 7 8} The associations seen at 9-11 years were similar to those observed by Cater and Gill⁵ but considerably stronger than those reported by other workers.^{2 12} The association was smoothly graded, with no evidence of the U shaped relation suggested by Launer et al.²¹ The results are consistent with our earlier report in suggesting that attained birth weight is the important factor in the relation between birth weight and blood pressure,⁸ regardless of the degree of intrauterine growth retardation.

PLACENTAL WEIGHT AND BLOOD PRESSURE

Our results do not support the hypothesis that placental weight or the ratio of placental weight to birth weight is a useful marker of higher subsequent blood pressure. In this study, as in an earlier, small study of 7 and 18 year olds,²² placental weight was inversely related to blood pressure. However, placental weight showed little relation with blood pressure once birth weight was taken into account, and placental ratio was unrelated to blood pressure.

CHANGE IN RELATION WITH AGE

This is one of the first longitudinal studies to examine the way in which the birth weight and blood pressure relation develops with age directly--an issue of direct relevance to the possibility of programming.¹³ Our results suggest that the inverse relation between birth weight and blood pressure emerges during the first five years after birth and that the relation becomes stronger (that is, "amplified") between 5-7 and 9-11 years. The increasing strength of the relation is not an artefact of cuff size or of other aspects of the measuring procedures used. However, it is observed only for systolic pressure and seems to be more pronounced in girls. This is surprising given the greater physical maturity of girls at this age and the inconsistent findings of earlier studies of the birth weight and blood pressure association in adolescence.^{9 10 11} However, the greater strength of the relations between birth weight and blood pressure at 9-11 years in this study compared with earlier studies^{2 12} emphasises the importance of substantiating the finding in other longitudinal studies.

It is also important that the relation between amplification and "programming" is defined. In particular, agreement is needed on whether amplification alone is evidence of programming or whether a particular mechanism of amplification is required. Theoretically, the birth weight and blood pressure relation could be amplified simply by blood pressure tracking combined with the dispersion of the blood pressure distribution which occurs with age (fig 2). Whether amplification occurring by this mechanism (option (a)) is evidence of programming or whether evidence of systematic upward "detracking" across the blood pressure distribution by children of low birth weight (option (b)) is required (fig 2) has still to be established. Our present results provide some support for the possibility of detracking--though only in girls--and emphasise the need for further longitudinal studies of the relation between early life factors and cardiovascular risk factor development.

View larger version (16K): [in this window] [in a new window]   FIG 2--Systolic blood pressure centiles between 6 and 10 years of age. Centiles are based on data from 549 children studied longitudinally, measured at mean ages of 6.2 and 9.9 years and are standardised for sex, height, and body mass index. (See text for options (a) and (b))

Two of us (PW and MW) were supported by the British Heart Foundation and one (OP) by the Stroke Association. We thank the research team (Jane King, Susan Wright, Joan Branthwaite) and the education authorities, schools, parents, and children for their cooperation and local directors of public health and hospital medical records departments for their help.

Funding: Medical Research Council and Coronary Artery Disease Research Association.

Conflict of interest: None.

1. Barker DJP, ed. The fetal and infant origins of adult disease. London: BMJ Publishing Group, 1992.
2. Barker DJP, Osmond C, Golding J, Kuh D, Wadsworth MEJ. Growth in utero, blood pressure in childhood and adult life, and mortality from cardiovascular disease. BMJ 1989;298:564-7.
3. Barker DJP, Bull AR, Osmond C, Simmonds SJ. Fetal and placental size and risk of hypertension in adult life. BMJ 1990;301:259-62.
4. Gennser G, Rymark P, Isberg PE. Low birth weight and risk of high blood pressure in adulthood. BMJ 1988;296:1498-500.
5. Cater J, Gill M. The follow-up study: medical aspects. In: Illsey R, Mitchell RG, eds. Low birth weight, a medical psychological and social study. Chichester: John Wiley, 1984:191-205.
6. Whincup PH, Cook DG, Shaper AG. Early influences on blood pressure: a study of children aged 5-7 years. BMJ 1989;299:587-91.
7. Law CM, Barker DJP, Bull AR, Osmond C. Maternal and fetal influences on blood pressure. Arch Dis Child 1991;66:1291-5. [Abstract/Free Full Text]
8. Whincup PH, Cook DG, Papacosta O. Do maternal and intrauterine factors influence blood pressure in childhood? Arch Dis Child 1992;67:1423-9.
9. MacIntyre S, Watt G, West P, Ecob R. Correlates of blood pressure in the west of Scotland. J Epidemiol Community Health 1991;45:143-7. [Abstract/Free Full Text]
10. Seidman DS, Laor A, Gale R, Stevenson DK, Mashiach S, Danon YL. Birth weight, current body weight, and blood pressure in late adolescence. BMJ 1991;302:1235-6.
11. Matters JWA, Lewis PA, Davies DP, Bethel JA. Relation between birth weight at term and systolic blood pressure in adolescence. BMJ 1994;308:1074-7. [Abstract/Free Full Text]
12. Law CM, de Swiet M, Osmond C, Fayers P, Barker DJP, Cruddas AM, et al. Initiation of hypertension in utero and its amplification throughout life. BMJ 1993;306:24-7.
13. Lucas A. Programming by early nutrition in man. In: Buck GR, Whelan J, eds. The childhood environment and adult disease. Chichester: John Wiley, 1991:38-55. (Ciba Foundation symposium No 156.)
14. Whincup PH, Papacosta O, Cook DG. Initiation of hypertension in utero. BMJ 1993;306:584. [Free Full Text]
15. Whincup PH, Cook DG, Shaper AG, Macfarlane D, Walker M. Blood pressure in British children: associations with adult blood pressure and cardiovascular mortality. Lancet 1988;ii:890-3.
16. Whincup PH, Cook DG, Papacosta O, Walker M, Perry I. Maternal factors and development of cardiovascular risk: evidence from a study of blood pressure in children. J Hum Hypertens 1994;8:337-43. [Medline]
17. Whincup PH, Bruce NG, Cook DG, Shaper AG. The Dinamap 1846SX oscillometric blood pressure recorder: comparison with the Hawksley random-zero sphygmomanometer under field study conditions. J Epidemiol Community Health 1992;46:164-9. [Abstract/Free Full Text]
18. Whincup PH, Cook DG, Shaper AG. Blood pressure measurement in children: the importance of cuff size. J Hypertens 1989;7:845-50. [Medline]
19. Frohlich ED, Grim C, Labarthe DR, Maxwell MH, Perioff D, Weidman WH. Recommendations for human blood pressure determinations by sphygmomanometers. Report of a special task force appointed by the steering committee, American Heart Association. Circulation 1988;77:502-14A.
20. SAS Institute Inc. SAS user's guide: basics and statistics (version 5). Cary, North Carolina: SAS Institute, 1985.
21. Launer LJ, Hofman A, Grobbee DE. Relation between birth weight and blood pressure: longitudinal study of infants and children. BMJ 1993;307:1451-4.
22. Williams SA, St George IM, Silva PA. Intrauterine growth retardation and blood pressure at ages seven and eighteen. Journal of Chronic Diseases 1992;45:1257-63.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    StumbleUpon    Technorati    What's this?

This article has been cited by other articles:

• Reinehr, T., Kleber, M., Toschke, A. M. (2009). Small for gestational age status is associated with metabolic syndrome in overweight children. Eur J Endocrinol 160: 579-584 [Abstract] [Full text]  
• Mzayek, F., Hassig, S., Sherwin, R., Hughes, J., Chen, W., Srinivasan, S., Berenson, G. (2007). The Association of Birth Weight with Developmental Trends in Blood Pressure from Childhood through Mid-Adulthood: The Bogalusa Heart Study. Am J Epidemiol 166: 413-420 [Abstract] [Full text]  
• Menezes, A. M. B., Hallal, P. C., Horta, B. L., Araujo, C. L. P., de Fatima Vieira, M., Neutzling, M., Barros, F. C., Victora, C. G. (2007). Size at Birth and Blood Pressure in Early Adolescence: A Prospective Birth Cohort Study. Am J Epidemiol 165: 611-616 [Abstract] [Full text]  
• Chiolero, A., Bovet, P., Paradis, G., Paccaud, F. (2007). Has Blood Pressure Increased in Children in Response to the Obesity Epidemic?. Pediatrics 119: 544-553 [Abstract] [Full text]  
• Franco, M. C.P., Christofalo, D. M.J., Sawaya, A. L., Ajzen, S. A., Sesso, R. (2006). Effects of Low Birth Weight in 8- to 13-Year-Old Children: Implications in Endothelial Function and Uric Acid Levels. Hypertension 48: 45-50 [Abstract] [Full text]  
• Zandi-Nejad, K., Luyckx, V. A., Brenner, B. M. (2006). Adult Hypertension and Kidney Disease: The Role of Fetal Programming. Hypertension 47: 502-508 [Abstract] [Full text]  
• Hardy, R., Sovio, U., King, V. J., Skidmore, P. M.L., Helmsdal, G., Olsen, S. F., Emmett, P. M., Wadsworth, M. E.J., Jarvelin, M.-R., the EURO-BLCS Study Group, (2006). Birthweight and blood pressure in five European birth cohort studies: an investigation of confounding factors. Eur J Public Health 16: 21-30 [Abstract] [Full text]  
• Leon, D. A., Koupil, I., Mann, V., Tuvemo, T., Lindmark, G., Mohsen, R., Byberg, L., Lithell, H. (2005). Fetal, Developmental, and Parental Influences on Childhood Systolic Blood Pressure in 600 Sib Pairs: The Uppsala Family Study. Circulation 112: 3478-3485 [Abstract] [Full text]  
• Primatesta, P., Falaschetti, E., Poulter, N. R. (2005). Birth Weight and Blood Pressure in Childhood: Results From the Health Survey for England. Hypertension 45: 75-79 [Abstract] [Full text]  
• Falkner, B., Hulman, S., Kushner, H. (2004). Effect of Birth Weight on Blood Pressure and Body Size in Early Adolescence. Hypertension 43: 203-207 [Abstract] [Full text]  
• Martin, R. M, McCarthy, A., Smith, G. D., Davies, D. P, Ben-Shlomo, Y. (2003). Infant nutrition and blood pressure in early adulthood: the Barry Caerphilly Growth study. Am. J. Clin. Nutr. 77: 1489-1497 [Abstract] [Full text]  
• Forsyth, J S, Willatts, P, Agostoni, C, Bissenden, J, Casaer, P, Boehm, G (2003). Long chain polyunsaturated fatty acid supplementation in infant formula and blood pressure in later childhood: follow up of a randomised controlled trial. BMJ 326: 953-953 [Abstract] [Full text]  
• Horta, B L, Barros, F C, Victora, C G, Cole, T J (2003). Early and late growth and blood pressure in adolescence. J. Epidemiol. Community Health 57: 226-230 [Abstract] [Full text]  
• Lawlor, D. A., Ebrahim, S., Davey Smith, G. (2002). Is There a Sex Difference in the Association between Birth Weight and Systolic Blood Pressure in Later Life? Findings from a Meta-Regression Analysis. Am J Epidemiol 156: 1100-1104 [Abstract] [Full text]  
• Walker, S P, Gaskin, P, Powell, C A, Bennett, F I, Forrester, T E, Grantham-McGregor, S (2001). The effects of birth weight and postnatal linear growth retardation on blood pressure at age 11-12 years. J. Epidemiol. Community Health 55: 394-398 [Abstract] [Full text]  
• Livshits, G., Gerber, L. M. (2001). Familial Factors of Blood Pressure and Adiposity Covariation. Hypertension 37: 928-935 [Abstract] [Full text]  
• Stevenson, C J, West, C R, Pharoah, P O D (2001). Dermatoglyphic patterns, very low birth weight, and blood pressure in adolescence. Arch. Dis. Child. Fetal Neonatal Ed. 84: 18F-22 [Abstract] [Full text]  
• Eriksson, J., Forsen, T., Tuomilehto, J., Osmond, C., Barker, D. (2000). Fetal and Childhood Growth and Hypertension in Adult Life. Hypertension 36: 790-794 [Abstract] [Full text]  
• Leon, D. A., Johansson, M., Rasmussen, F. (2000). Gestational Age and Growth Rate of Fetal Mass Are Inversely Associated with Systolic Blood Pressure in Young Adults: An Epidemiologic Study of 165,136 Swedish Men Aged 18 Years. Am J Epidemiol 152: 597-604 [Abstract] [Full text]  
• O'Sullivan, J. J, Pearce, M. S, Parker, L. (2000). Parental recall of birth weight: how accurate is it?. Arch. Dis. Child. 82: 202-203 [Abstract] [Full text]  
• Dwyer, T., Blizzard, L., Morley, R., Ponsonby, A.-L. (1999). Within pair association between birth weight and blood pressure at age 8 in twins from a cohort study. BMJ 319: 1325-1329 [Abstract] [Full text]  
• Pharoah, P O D, Stevenson, C J, West, C R (1998). Association of blood pressure in adolescence with birthweight. Arch. Dis. Child. Fetal Neonatal Ed. 79: 114F-118 [Abstract] [Full text]  
• Woelk, G., Emanuel, I., Weiss, N. S, Psaty, B. M (1998). Birthweight and blood pressure among children in Harare, Zimbabwe. Arch. Dis. Child. Fetal Neonatal Ed. 79: 119F-122 [Abstract] [Full text]  
• Laor, A., Stevenson, D. K, Shemer, J., Gale, R., Seidman, D. S (1997). Size at birth, maternal nutritional status in pregnancy, and blood pressure at age 17: population based analysis. BMJ 315: 449-453 [Abstract] [Full text]  
• Belizan, J. M, Villar, J., Bergel, E., del Pino, A., Di Fulvio, S., Galliano, S. V, Kattan, C. (1997). Long term effect of calcium supplementation during pregnancy on the blood pressure of offspring: follow up of a randomised controlled trial. BMJ 315: 281-285 [Abstract] [Full text]  
• Uiterwaal, C. S. P. M., Anthony, S., Launer, L. J., Witteman, J. C. M., Trouwborst, A. M. W., Hofman, A., Grobbee, D. E. (1997). Birth Weight, Growth, and Blood Pressure : An Annual Follow-up Study of Children Aged 5 Through 21 Years. Hypertension 30: 267-271 [Abstract] [Full text]  
• Seckl, J. R., Miller, W. L. (1997). How Safe Is Long-term Prenatal Glucocorticoid Treatment?. JAMA 277: 1077-1079 [Abstract]  
• Geleijnse, J. M., Hofman, A., Witteman, J. C. M., Hazebroek, A. A. J. M., Valkenburg, H. A., Grobbee, D. E. (1997). Long-term Effects of Neonatal Sodium Restriction on Blood Pressure. Hypertension 29: 913-917 [Abstract] [Full text]  
• Taylor, S. J C, Whincup, P. H, Cook, D. G, Papacosta, O., Walker, M. (1997). Size at birth and blood pressure: cross sectional study in 8-11 year old children. BMJ 314: 475-475 [Abstract] [Full text]  
• Zureik, M., Bonithon-Kopp, C., Lecomte, E., Siest, G., Ducimetiere, P. (1996). Weights at Birth and in Early Infancy, Systolic Pressure, and Left Ventricular Structure in Subjects Aged 8 to 24 Years. Hypertension 27: 339-345 [Abstract] [Full text]