title: Reduced spontaneous platelet aggregation: a novel risk factor for adverse pregnancy outcome.
abstract: OBJECTIVE
  Spontaneous platelet aggregation has not been adequately assessed as a potential risk factor for adverse outcomes in pregnancy. Therefore the objective of this study was to assess spontaneous platelet aggregation (SPA), measured via a novel functional assay, as a risk factor for hypertensive disease and intra-uterine growth restriction (IUGR).
  
  
  METHODS
  This was a prospective longitudinal study. Spontaneous platelet aggregation was assessed as a marker of platelet reactivity using a modification of light transmission aggregometry. Platelet reactivity was assessed in four groups: non-pregnant healthy female volunteers (n=30), longitudinally in normal uncomplicated pregnancy (n=50), hypertensive disorder (n=40) and IUGR (n=30). The mean percentage SPA was plotted and compared across all groups.
  
  
  RESULTS
  Spontaneous platelet aggregation was significantly reduced in the first trimester compared to the non-pregnant group (p-value=0.003). The mean aggregation for the hypertensive group was 1.9%, (95% CI -0.08 to 4.02) and for the IUGR group was 1.6%, (95% CI -0.6 to 3.72). Platelet aggregation in the hypertensive group was significantly reduced compared to the normal pregnant group (p<0.05). Spontaneous platelet aggregation was also reduced in the IUGR group compared to normal pregnancy (p<0.05).
  
  
  CONCLUSIONS
  This study demonstrates that a reduction of spontaneous platelet aggregation may be a novel risk factor for adverse pregnancy outcomes such as pre-eclampsia and IUGR. The most clinically significant finding is that SPA is significantly lower in pregnancies complicated by hypertension and IUGR compared to those who had a normal pregnancy outcome. Further studies should be carried out to asses if spontaneous platelet aggregation may be a clinically useful tool for the prediction of pre-eclampsia and IUGR.
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland. Electronic address: burke.naomi@gmail.com.
authors.forename: Naomi
authors.initials: N
authors.lastname: Burke
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Karen
authors.initials: K
authors.lastname: Flood
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Sieglinde
authors.initials: S
authors.lastname: Muellers
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Aoife
authors.initials: A
authors.lastname: Murray
authors.affiliation: Dept of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, Ireland.
authors.forename: Eimear
authors.initials: E
authors.lastname: Dunne
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Brian
authors.initials: B
authors.lastname: Cotter
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Mark
authors.initials: M
authors.lastname: Dempsey
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Dicker
authors.affiliation: Dept of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Geary
authors.affiliation: Dept of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, Ireland.
authors.forename: Dermot
authors.initials: D
authors.lastname: Kenny
authors.affiliation: Royal College of Surgeons in Ireland, Dept. of Obstetrics and Gynecology, Rotunda Hospital, Dublin, Ireland.
authors.forename: Fergal D
authors.initials: FD
authors.lastname: Malone
mesh_terms: D000328:Adult; D001791:Blood Platelet Disorders / Q000097:blood / Q000150:complications*; D005260:Female; D005317:Fetal Growth Retardation / Q000097:blood / Q000209:etiology*; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications*; D010974:Platelet Aggregation / Q000502:physiology*; D011247:Pregnancy; D011256:Pregnancy Outcome; D012307:Risk Factors
keywords: Aggregation; Hypertension; Intra-uterine growth restriction; Normal pregnancy; Platelets; Spontaneous