The relationship between intrauterine foetal growth trajectories and blood pressure in young adults.

BACKGROUND

Previous studies have reported an association between low birthweight and elevated blood pressure (BP) in adulthood, but few have examined the relationship between foetal growth and adult BP.

METHOD: The study examined the association between intrauterine growth trajectories determined by serial ultrasound and BP of the adult offspring in the Raine Study. Foetal growth trajectories for abdominal circumference, femur length and head circumference z-scores were developed using group-based trajectory modelling from 1440 women with serial ultrasounds from 15-weeks pregnancy to birth. Seven abdominal circumference, five femur length and five head circumference trajectory groups were identified. Longitudinal linear mixed modelling examined the association between trajectory groups and offspring BP at 20 (n = 487), 22 (n = 419) and 27 (n = 436) years.

RESULTS

Higher SBP in adulthood significantly associated with two abdominal circumference trajectories, one with the most restricted foetal growth [3.52 mmHg, 95% confidence interval (95% CI) = 1.20-5.83] and the other with sustained low-growth (1.92 mmHg, 95% CI = 0.11-3.73) compared with an average growth trajectory, after adjusting for sex, age, alcohol consumption and BMI. Foetal head circumference trajectories with sustained low-growth or average-to-falling growth significantly associated with higher adult systolic (3.45 mmHg, 95% CI = 1.77-5.14 and 1.54 mmHg, 95% CI = 0.30-2.78, respectively) and diastolic (2.28 mmHg, 95% CI = 0.77-3.78 and 1.47 mmHg, 95% CI = 0.54-2.39, respectively) BP compared with average growth. Low femur length growth associated with higher adult DBP after adjusting for sex, but not after accounting for adult BMI.

CONCLUSION

Our results show that restricted foetal head and abdominal circumference associated with higher adult SBP over two decades later, reinforcing the importance of the early intrauterine environment and its influence on adult BP.