Abnormal maternal cardiac function precedes the clinical manifestation of fetal growth restriction

To compare maternal hemodynamics in women whose fetuses are small-for-gestational age (SGA) with those in women with fetal growth restriction (FGR) before manifestation of the clinical disease.

Thirty-five normotensive pregnant women with fetal abdominal circumference < 10th centile, normal fetal anatomy and normal umbilical artery pulsatility index (PI) underwent maternal echocardiographic examinations between 27 and 30 weeks of gestation. Pregnancies were followed until delivery and fetuses were retrospectively classified as either SGA or FGR and the maternal hemodynamic data were compared.

Nineteen SGA and 16 FGR patients were retrospectively identified after delivery. Heart rate, stroke volume, cardiac output, left atrial function and left ventricular mass index were higher, while mean blood pressure and total vascular resistance were lower in the SGA group compared with the FGR group. A significant inverse linear correlation was found between total vascular resistance and weight centile (r = 0.83; P < 0.0001).

Mothers of SGA fetuses show hemodynamic features similar to those with physiological pregnancies suggesting that their fetuses are likely to be constitutionally small and not pathologically growth-restricted.