Maternal cardiovascular disease risk in relation to the number of offspring born small for gestational age: national, multi-generational study of 2.7 million births.

Abstract Aim: To investigate the risk of small for gestational age (SGA) births in relation to maternal history of cardiovascular disease (CVD) across two generations and additionally to analyse maternal CVD risk based on number of SGA offspring. Methods: We used register data from 1.4 million women and 2.7 million offspring. The outcome measures were risk of being SGA in relation to maternal total CVD (n = 10 436) across two generations, as well as risk of CVD in mothers in relation to the number of their SGA offspring, stratified by educational level. Results: Compared to no family history of CVD (reference) the hazard ratio (HR) for being SGA in female offspring was 1.11 (95% confidence interval (CI) 1.09-1.13) for a positive maternal history of CVD. The highest risk was shown in daughters when both the mother and the grandmother had a history of CVD (HR 1.32, 95% CI 1.24-1.39). There was a stepwise increased risk of CVD events in mothers in relation to the number of their SGA offspring (HR 1.41-1.86) when 'no SGA offspring' was used as reference. The risk of CVD in relation to SGA status was increased in the least educated group (HR 2.7-5.0) compared to the group with the highest level of education with no SGA offspring. Conclusion: The risk of SGA offspring and the risk of maternal CVD are mutually interdependent and both conditions increased in women with a low level of education.