Relationship of first-trimester uterine artery Doppler to late stillbirth.

OBJECTIVE: The aim of this study was to investigate if increased first-trimester uterine artery Doppler resistance indices (RI) are related to stillbirth. METHOD: Uterine artery Doppler indices were assessed prospectively during a routine first-trimester ultrasound scan. Patients were categorised as having a high uterine artery mean Doppler RI if the index was above the 90th centile for gestation. Stillbirth outcomes were ascertained from a mandatory national register of pregnancy losses. RESULTS: High RI uterine artery Doppler (>90th centile) was an independent risk factor for late (≥ 34 weeks) but not early stillbirth, with a hazard ratio of 2.61 (95% CI 1.13-6.03). The inclusion of uterine artery Doppler indices into Cox proportional hazard model negated the influence of conventional risk factors for stillbirth, such as parity, maternal age and body mass index (BMI), but not Afro-Caribbean ethnicity or smoking. CONCLUSION: High first-trimester uterine artery Doppler RI is associated with late stillbirth after 34 weeks' gestation. This association supersedes those of conventional risk factors such as maternal age, parity and BMI, implying that these factors result in an increased risk of stillbirth by causing placental dysfunction.

Pre-eclampsia and fetal growth restriction: how morphometrically different is the placenta?

Both pre-eclampsia (PET) and fetal growth restriction (FGR) pose a heavy burden on fetal and maternal health and may disrupt pregnancy outcome. Using design based stereological techniques, placental vascular and villous morphology were assessed to determine the individual role played by both PET and FGR on placental growth during the third trimester. The following placentas delivered between 25 and 41 weeks of gestation were included into the study; controls (n=16), PET (n=20), FGR (n=17) and PET-FGR (n=16). Each placenta was uniformly randomly sampled and the sampled tissue processed to paraffin. Sections were stained with a CD34 antibody and the following morphometric parameters estimated: volumes, surface areas, length, diameters and the shape factor of the villous (terminal and intermediate) and vascular placental features. For stereologically estimated parameters pure PET had an effect on IVS and terminal villi volume only. FGR alone or when coexisting with PET contributed towards significant reductions in volumetric and surface area terminal villous and vascular features. FGR factors also contributed towards a significant reduction in the lengths of all parameters estimated and in the terminal villi diameter. Additionally, FGR was associated with a significant difference in shape factor indices for both intermediate and terminal villi. This study has shown that PET on its own has limited influence on the placental morphology studied, since the vascular features estimated do not differ stereologically from age matched normal controls. However, placental morphology is different between PET and PET-FGR and between PET-FGR and FGR. PET and FGR may have a cumulative effect on placental villous and vascular morphology as seen in the PET-FGR but there is no synergistic effect. These morphological abnormalities may have major physiological implications in terms of placental function and fetal growth.

Pregnancy-associated atypical haemolytic uraemic syndrome in the postpartum period: a case report and review of the literature.

Pregnancy has been reported to be a trigger in about 10% of all patients with atypical haemolytic uraemic syndrome (aHUS). However, in contrast to pregnancy-associated thrombotic thrombocytopaenic purpura, the presentation of pregnancy-associated aHUS remains ill defined and can therefore be difficult to diagnose and manage appropriately. Here we report a case of pregnancy-associated relapse of aHUS in a patient with a previous medical history of aHUS prior to pregnancy.

Morphometric placental villous and vascular abnormalities in early- and late-onset pre-eclampsia with and without fetal growth restriction.

OBJECTIVE: To evaluate placental morphology in pregnancies complicated by early- and late-onset pre-eclampsia (PET) with and without fetal growth restriction (FGR) using stereological techniques. DESIGN: A total of 69 pregnant women were studied. Twenty women had pregnancies complicated by PET, 17 by FGR and 16 by both PET and FUR; the remaining 16 were from gestational-age-matched controls. Each group was further classified into early onset (<34 weeks) and late onsets (>34 weeks) based on gestational ages. SETTING: NPIMR at Northwick Park and St Marks Hospital. POPULATION: placentae from pregnant women. METHODS: Formalin-fixed, wax-embedded sections stained with anti-CD34 antibodies and counterstained with haematoxylin. MAIN OUTCOME MEASURES: Volumes, surface areas, lengths, diameters and shape factors of the villous tissues and fetal vasculature in the intermediate and terminal villi of all the groups studied. RESULTS: Terminal villi volume and surface area were compromised in early-onset PET cases, late-onset PET had no impact on peripheral villi or vasculature features. The morphology of the vascular and villous subcomponents in the intermediate and terminal villi was significantly influenced by late-onset FGR, whereas early-onset FGR caused a reduction in placental weight. Length estimates were not influenced by PET, FGR or age of onset. Intermediate arteriole shape factor was significantly reduced in late-onset FGR. CONCLUSIONS: Isolated early-onset PET was associated with abnormal placental morphology, but placentas from late-onset PET were morphologically similar to placentas from gestational-age-matched controls, confirming the existence of two subsets of this condition and supporting the hypothesis that late-onset PET is a maternal disorder and not a placental disease.