Umbilical artery Doppler in relation to placental pathology and FV Leiden in pregnant women and their offspring

Stillbirth and factor V Leiden - A regional based prospective evaluation

BACKGROUND

Approximately 10% of Swedes are carriers of coagulation factor V Leiden (FVL). It has been suggested that carriers are at an increased risk of stillbirth. We aimed to assess the risk of stillbirth in carriers of FVL as compared to non-carriers.

METHODS

A consecutive registration of all stillbirths from 2001 to 2015 in the whole Stockholm region has been performed. A FVL blood sample, an autopsy and histopathological examination of the placenta was scheduled to be offered all women with stillbirth. Main outcome was the difference in carriership of FVL between cases with live- vs. stillbirth. The primary cause of death was determined according to the Stockholm hierarchical classification of stillbirth.

RESULTS

The incidence of stillbirth was 3.6‰. Out of the 1392 cases of stillbirth occurring during the study period, FVL status was determined in 963 women. Of these 74 (7.7%) were carriers of FVL as compared to 8.1% in the control group (p = 0.6). A primary cause of death due to infection was twice as common among non-carriers compared to carriers of FVL (odds ratio [OR] = 2.3, 95% CI 1.08-4.8). In the whole study group, the prevalence of SGA was 14-fold increased among stillbirths as compared to live births (OR = 13.9, 95% CI 12.4-15.6).

CONCLUSION

Maternal FVL carriership was not related to an increased risk of stillbirth. However, a diagnosis of primary cause of death due to infection was less likely among FVL carriers.

Arginine vasopressin infusion is sufficient to model clinical features of preeclampsia in mice

Copeptin, a marker of arginine vasopressin (AVP) secretion, is elevated throughout human pregnancies complicated by preeclampsia (PE), and AVP infusion throughout gestation is sufficient to induce the major phenotypes of PE in mice. Thus, we hypothesized a role for AVP in the pathogenesis of PE. AVP infusion into pregnant C57BL/6J mice resulted in hypertension, renal glomerular endotheliosis, intrauterine growth restriction, decreased placental growth factor (PGF), altered placental morphology, placental oxidative stress, and placental gene expression consistent with human PE. Interestingly, these changes occurred despite a lack of placental hypoxia or elevations in placental fms-like tyrosine kinase-1 (FLT1). Coinfusion of AVP receptor antagonists and time-restricted infusion of AVP uncovered a mid-gestational role for the AVPR1A receptor in the observed renal pathologies, versus mid- and late-gestational roles for the AVPR2 receptor in the blood pressure and fetal phenotypes. These findings demonstrate that AVP is sufficient to initiate phenotypes of PE in the absence of placental hypoxia, and indicate that AVP may mechanistically (independently, and possibly synergistically with hypoxia) contribute to the development of clinical signs of PE in specific subtypes of human PE. Additionally, they identify divergent and gestational time-specific signaling mechanisms that mediate the development of PE phenotypes in response to AVP.

The relationship between human placental morphometry and ultrasonic measurements of utero-placental blood flow and fetal growth

INTRODUCTION

Ultrasonic fetal biometry and arterial Doppler flow velocimetry are widely used to assess the risk of pregnancy complications. There is an extensive literature on the relationship between pregnancy outcomes and the size and shape of the placenta. However, ultrasonic fetal biometry and arterial Doppler flow velocimetry have not previously been studied in relation to postnatal placental morphometry in detail.

METHODS

We conducted a prospective cohort study of nulliparous women in The Rosie Hospital, Cambridge (UK). We studied a group of 2120 women who had complete data on uterine and umbilical Doppler velocimetry and fetal biometry at 20, 28 and 36 weeks' gestational age, digital images of the placenta available, and delivered a liveborn infant at term. Associations were expressed as the difference in the standard deviation (SD) score of the gestational age adjusted ultrasound measurement (z-score) comparing the lowest and highest decile of the given placental morphometric measurement.

RESULTS

The lowest decile of placental surface area was associated with 0.87 SD higher uterine artery Doppler mean pulsatility index (PI) at 20 weeks (95% CI: 0.68 to 1.07, P < 0.001). The lowest decile of placental weight was associated with 0.73 SD higher umbilical artery Doppler PI at 36 weeks (95% CI: 0.54 to 0.93, P < 0.001). The lowest decile of both placental weight and placental area were associated with reduced growth velocity of the fetal abdominal circumference between 20 and 36 weeks (both P < 0.001).

CONCLUSION

Placental area and weight are associated with uterine and umbilical blood flow, respectively, and both are associated with fetal growth rate.