ArticlesPregnancy complications and maternal risk of ischaemic heart disease: a retrospective cohort study of 129 290 births
Introduction
Previous studies have shown an association between an individual's birthweight and his or her subsequent risk of ischaemic heart disease (IHD), hypertension, and diabetes mellitus.1 Barker and colleagues have postulated that fetal adaptation to inadequate intrauterine nutrition, due to poor maternal diet or placental dysfunction, results in physiological programming of a “thrifty phenotype”, which increases the risk of hypertension and IHD in later life. Babies might be small either because they are born preterm or because their intrauterine growth is suboptimum. An alternative hypothesis is that common genetic factors predispose to intrauterine growth restriction, preterm birth, and IHD.2 If this hypothesis is true, mothers who have pregnancies complicated by intrauterine growth restriction or preterm delivery should themselves be at increased risk of developing IHD. This study aimed to assess whether complications of pregnancy linked with low birthweight are associated with the mother's subsequent risk of IHD.
Section snippets
Selection of study cohort
The Scottish Morbidity Record (SMR) system collects routine discharge data on all patients admitted to Scottish National Health Service acute (SMR1) and maternity (SMR2) hospitals. The Information and Statistics Division of the Common Services Agency links all SMR records for an individual patient to each other and to the General Registrar's Office death database. The SMR2 system collects information on clinical and demographic characteristics and outcomes. Data on maternal smoking status have
Results
Between 1981 and 1985, 137 094 singleton first pregnancies resulted in the birth of a live infant. Data on gestational age at birth or birthweight were missing in 1142 (0·8%) cases. Of the remaining 135 952infants, 135 891 weighed at least 500 g at birth and were born between 24 and 43 weeks of gestation. Complete data on maternal age at the baby's birth, maternal height, and the infant's sex were available for 129 920 (95·6%). The case-mix and crude outcomes of the study cohort are summarised
Discussion
The main finding of this study is that there are additive associations between birthweight for gestational age, preterm birth, and a diagnosis of pre-eclampsia in the first pregnancy and the mother's risk of fatal and non-fatal IHD in later life (Table 2, Table 3). These associations were independent of maternal height and age, socioeconomic deprivation, and essential hypertension during pregnancy.
One possible explanation for the association between low birthweight quintile and risk of IHD is a
References (27)
Fetal origin of maturity-onset diabetes mellitus: genetic or environmental cause?
Med Hypotheses
(1998)- et al.
Clinical profile and long-term prognosis of women < or =50 years of age referred for coronary angiography for evaluation of chest pain
Am J Cardiol
(2000) - et al.
A common prothrombin variant (20210 G to A) increases the risk of myocardial infarction in young women
Blood
(1997) - et al.
Factor V Leiden (resistance to activated protein C) increases the risk of myocardial infarction in young women
Blood
(1997) - et al.
A systematic review and meta-analysis of prospective studies on the association between maternal cigarette smoking and preterm delivery
Am J Obstet Gynecol
(2000) - et al.
Cigarette smoking during pregnancy and risk of preeclampsia: a systematic review
Am J Obstet Gynecol
(1999) Maternal weight gain, infant birth weight, and diet: causal sequences
Am J Clin Nutr
(1991)- et al.
Association of maternal G protein beta3 subunit 825T allele with low birthweight
Lancet
(2000) Hypertension in pregnancy: definitions, familial factor, and remote prognosis
Kidney Int
(1980)Mother's, babies and disease in later life
(1994)