Placental hormones as putative markers of gestational diseases
C. Voltolini, M. Torricelli, C. Bocchi, M. De Bonis, F. Severi & F. Petraglia
Preterm delivery (PTD) and preeclampsia (PE) are obstetric syndromes, characterized by complex pathogenesis and representing major causes of perinatal mortality and morbidity. Although therapeutical treatment have been developed, their incidence is not reducing. Prevention aims to preclude development of disease by eliminating/reducing risk in women with known risk factors.
The feto-placental unit produces hormonal/neuronal/immune factors, crucial in maintaining feto-placental homeostasis, that are abnormally secreted in gestational diseases as part of pathogenetic mechanisms and/or feto-maternal adaptive response. Corticotrophin releasing hormone (CRH) and inhibin/activin, expressed by trophoblast, locally modulate hormone secretion, blood vessel tone, myometrial contractility, inflammatory events. Their measurement in biological fluids has been investigated to find putative biochemical markers for early diagnosis/prediction of these conditions.
PE is characterized by poor placentation due to impeded transformation of spiral arteries into low resistance vessels. Uterine artery Doppler at mid gestation allows to screen high-risk population through early detection of abnormally high resistance uteroplacental blood flow. Maternal serum activin A and inhibin A are high at 12 and 24 weeks in patients later developing PE. sFLT-1, soluble VEGF receptor neutralizing angiogenic actions of VEGF and PlGF, is elevated in women developing PE.
Spontaneous PTD is characterized by pathological and premature onset of labor and the ultrasound measurement of cervical length and, more recently, fetal membrane thickness are useful predictors of PTD. High maternal plasma CRH can predict delivery within 48 hours in symptomatic and within 34 weeks in asymptomatic women. High plasma urocortin levels predict delivery within 34 weeks in women with threatened PTD. High salivary estriol levels predict PTD with good accuracy and plasma estriol/estradiol ratio is altered before the onset of preterm labor.
Given the complex pathogenesis of PTD and PE, a multiple approach through the combination of biophysical and biochemical parameters may add significant prognostic information in women at risk.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.