Congenital Heart Defects and Indices of Placental and Fetal Growth in a Nationwide Study of 924,422 Liveborn Infants
Background—Congenital heart defects (CHD) have been associated with placental anomalies. The nature and the consequences of this association remain poorly understood. We aimed to estimate the associations between all major subtypes of CHD and placental weight at birth as well as the association between placental weight and measures of both overall and cerebral growth in fetuses with CHD.
Methods—We included all 924,422 liveborn Danish singletons, 1997-2011. CHD was present in 7,569. We compared mean differences in placental weight z-score between newborns with CHD and newborns without CHD by multivariable linear regression adjusted for potential confounders.
Results—CHD was associated with a mean z-score difference of -0.04 (95%CI -0.07,-0.02). Some subtypes were associated with smaller placental size at birth: Tetralogy of Fallot -0.45 (95%CI -0.58, -0.31), double outlet right ventricle -0.48 (95%CI -0.87, -0.10), major ventricular septal defects -0.41 (95%CI -0.52, -0.29). Placental weight z-score was associated with birth weight and head circumference z-scores in all subtypes. In the three mentioned subtypes, the mean deviations from the population mean head circumference and birth weight z-scores were reduced by up to 66 % with adjustment for placental weight z-score.
Conclusions—Three subtypes of CHD were associated with lower placental weight, and placental weight was associated with measures of both overall growth and cerebral growth in fetuses with all subtypes of CHD. In certain subtypes, the described deviations in fetal growth were reduced by up to two thirds after adjustment for placental weight z-score.
- placental growth
- placental weight
- birth weight
- head circumference
- fetal growth
- congenital cardiac defect
- fetal development
- heart defects, congenital
- Received February 8, 2016.
- Revision received July 26, 2016.
- Accepted September 14, 2016.