Maternal subclinical vascular changes in fetal growth restriction with and without pre-eclampsia

Abstract

Objective To assess maternal vascular structure and function in pregnancies complicated by fetal growth restriction (FGR), in women with and without pre-eclampsia (PE) at the time of FGR diagnosis. Methods We evaluated 124 women with a pregnancy complicated by FGR, of whom 60 had PE and 64 did not, and compared these findings to those of 110 normal women (controls). The group of FGR pregnancies without PE was further subdivided according to gestational age at FGR diagnosis into early onset (< 32 weeks) or late onset (≥ 32 weeks). Maternal carotid intima-media thickness (IMT), blood pressure (BP), carotid artery distensibility (CD), circumferential wall stress (CWS) and inferior vena cava (IVC) collapsibility were assessed by ultrasound at the time of FGR diagnosis. Results Compared to controls, cases of FGR with PE showed increased maternal carotid IMT (0.425 (interquartile range (IQR), 0.381-0.486) vs 0.409 (IQR, 0.386-0.439) mm; P = 0.021), BP (mean, 109 (IQR, 101-117) vs 82 (IQR, 77-89) mmHg; P < 0.001) and CWS (19.7 (IQR, 17.0-22.7) vs 12.2 (IQR, 11.1-13.7) kPa; P < 0.001), and reduced CD (25.3 (IQR, 15.7-35.6) vs 31.9 (IQR, 25.4-41.1) kPa-1 × 10-3; P = 0.037) and IVC collapsibility indices (0.07 (IQR, 0.06-1.11) vs 0.10 (IQR, 0.06-0.13); P = 0.136). Similarly, compared to controls, in cases of FGR without PE maternal carotid IMT (0.436 (IQR, 0.392-0.476) mm; P = 0.001) and BP (88 (IQR, 81-95) mmHg; P < 0.001) were increased but CD and IVC collapsibility were similar. When analysis was subclassified according to gestational age at diagnosis, IMT and CWS were significantly increased only in early-onset FGR while BP was increased in both groups. Conclusion Normotensive women with pregnancy complicated by FGR share some subclinical vascular features with those of women with PE, which further reinforces the notion that, at least in a proportion of cases, there is a common placental disease that influences maternal cardiovascular features.