title: Why non-invasive maternal hemodynamics assessment is clinically relevant in early pregnancy: a literature review.
abstract: The maternal cardiovascular system adapts quickly when embryo implantation is recognized by the body. Those adaptations play an important role, as a normal cardiovascular adaptation is a requirement for a normal course of pregnancy. Disturbed adaptations predispose to potential hypertensive disorders further in pregnancy [1-3]. This report aims to briefly inform the obstetricians, general practitioners and midwives, who are the key players in detecting and treating hypertensive disorders during pregnancy.
  
  
  
  The PubMed database was used as main tool to find studies involving clearly defined first trimester hemodynamic changes in normal pregnancies and hypertensive pregnancies. In addition, the bibliographies of these studies were investigated for further relevant literature.
  
  
  
  A comprehensive overview is given concerning the normal adaptations in the cardiovascular tree in a first trimester pregnancy. Additionally, signs of abnormal cardiovascular changes observed in first trimester are described together with the normal reference range for each non-invasive, easily applicable technique for maternal hemodynamics assessment.
  
  
  
  With a combination of techniques, it is possible to integrate and evaluate the maternal heart, veins and arteries at 12 weeks of pregnancy. Applying those techniques into the daily clinic opens perspectives to prevention and prophylactic treatment, aiming for a reduction of the risk for hypertension during pregnancy.
authors.affiliation: Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium. sharona.vonck@zol.be.|Department of Obstetrics & Gynecology, Ziekenhuis Oost-Limburg, Schiepse Bos 6, 3600, Genk, Belgium. sharona.vonck@zol.be.
authors.forename: Sharona
authors.initials: S
authors.lastname: Vonck
authors.affiliation: Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium.|Department of Obstetrics & Gynecology, Ziekenhuis Oost-Limburg, Schiepse Bos 6, 3600, Genk, Belgium.
authors.forename: Anneleen Simone
authors.initials: AS
authors.lastname: Staelens
authors.affiliation: Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium.
authors.forename: Ine
authors.initials: I
authors.lastname: Bollen
authors.affiliation: Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium.
authors.forename: Lien
authors.initials: L
authors.lastname: Broekx
authors.affiliation: Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium.|Department of Obstetrics & Gynecology, Ziekenhuis Oost-Limburg, Schiepse Bos 6, 3600, Genk, Belgium.|Department Physiology, Hasselt University, Hasselt, Belgium.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Gyselaers
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000502:physiology*; D011296:Prenatal Diagnosis / Q000379:methods*
keywords: Early pregnancy; First trimester; Hypertension; Maternal hemodynamics; Reference values