title: Ambulatory arterial stiffness index is unchanged in uncomplicated third-trimester singleton and twin pregnancies.
abstract: OBJECTIVE
  To document the ambulatory arterial stiffness index (AASI) during pregnancy compared to three months after delivery in singleton and twin pregnancies.
  
  
  METHODS
  Descriptive study with a follow-up design.
  
  
  METHODS
  University hospital in Eastern Finland.
  
  
  METHODS
  43 childbearing women; 32 with singleton and 11 with twin pregnancies.
  
  
  METHODS
  Ambulatory blood pressure measurements were conducted using a digital ambulatory blood pressure system. AASI was calculated as 1 minus the regression slope of diastolic on systolic blood pressures obtained from 24-hour monitoring.
  
  
  METHODS
  Arterial stiffness measured by AASI.
  
  
  RESULTS
  In normotensive pregnant women, the 95th percentiles of AASI were 0.40 in singleton and 0.46 in twin pregnancies, respectively, implying arterial normality and high elasticity. There were no differences in AASI values between singleton and twin pregnancies and no changes were observed postpartum. After delivery, but not during pregnancy, AASI correlated negatively with nocturnal systolic and diastolic blood pressure reduction (dipping) (r=-0.536, p=0.001; r=-0.674, p<0.001) and with maternal HDL (r=-0.363, p=0.038) and positively with maternal age (r=0.440, p=0.009), whereas maternal BMI had a significant impact on AASI both during and after pregnancy (r=0.366, p=0.016; r=0.377, p=0.028).
  
  
  CONCLUSIONS
  Normal singleton or twin pregnancies had no detectable effects on AASI. However, pregnancy appeared to overcome the negative effects of low high-density lipoproteins, unfavorable dipping status and advanced maternal age on arterial stiffness, but not the effect caused by maternal body mass index.
authors.affiliation: Department of Obstetrics and Gynecology, Kuopio University Hospital, University of Eastern Finland, Finland. henna.karkkainen@kuh.fi
authors.forename: Henna
authors.initials: H
authors.lastname: Kärkkäinen
authors.forename: Nonna
authors.initials: N
authors.lastname: Heiskanen
authors.forename: Heli
authors.initials: H
authors.lastname: Saarelainen
authors.forename: Pirjo
authors.initials: P
authors.lastname: Valtonen
authors.forename: Tiina
authors.initials: T
authors.lastname: Lyyra-Laitinen
authors.forename: Tomi
authors.initials: T
authors.lastname: Laitinen
authors.forename: Esko
authors.initials: E
authors.lastname: Vanninen
authors.forename: Seppo
authors.initials: S
authors.lastname: Heinonen
mesh_terms: D000328:Adult; D000367:Age Factors; D001158:Arteries / Q000502:physiology* / Q000503:physiopathology; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D015992:Body Mass Index; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008055:Lipids / Q000097:blood; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000503:physiopathology; D011263:Pregnancy Trimester, Third; D011446:Prospective Studies; D013997:Time Factors; D014427:Twins; D014655:Vascular Resistance
chemical_list: D001786:Blood Glucose; D008055:Lipids