title: Determination of placental growth factor (PlGF) levels in healthy pregnant women without signs or symptoms of preeclampsia.
abstract: OBJECTIVE
  To identify a reference range for placental growth factor (PlGF) in normotensive women without symptoms or signs of preeclampsia.
  
  
  METHODS
  Comprising the study cohort were 247 term pregnancies without preeclampsia or adverse neonatal outcomes from 16 sites in the US and Canada. Serial plasma samples were collected in 6 gestational age (GA) intervals between 20+0 and 40+0weeks. Non-parametric percentiles of the distribution of PlGF were estimated in each GA interval and a parametric model was developed to describe the distribution of PlGF as a continuous smooth function of GA (from 20 to 40weeks) in normal healthy pregnancy. Demographic and clinical factors influencing PlGF levels were also examined.
  
  
  RESULTS
  There were 1366 evaluable samples collected from 247 subjects (242, 238, 226, 223, 222, and 215 samples in each GA interval, 20-24, 24-29, 29-32, 32-35, 35-37, and 37-40weeks, respectively). The 5th percentile of PlGF was 76.4, 141.1, 139.3, 65.5, 31.7, and 23.4pg/mL in each respective GA interval. The distribution of PlGF is approximately log normal with parameters that vary continuously as a function of GA. PlGF distribution is weakly dependent on maternal age, race/ethnicity, parity, and maximum systolic blood pressure (taken between weeks 20 and 24). Although statistically significant, these factors did not modify PlGF levels by more than ±15%.
  
  
  CONCLUSIONS
  These data provide a valid reference range for PlGF in normal pregnancy.
authors.affiliation: West Coast OB/GYN, 7910 Frost St., Suite 400, San Diego, CA 92123, United States. Electronic address: csaffer@pol.net.
authors.forename: Craig
authors.initials: C
authors.lastname: Saffer
authors.affiliation: University of Texas Medical Branch, 3.400 Old John Sealy, 301 University Blvd, Galveston, TX 77555, United States. Electronic address: golson@utmb.edu.
authors.forename: Gayle
authors.initials: G
authors.lastname: Olson
authors.affiliation: University of North Carolina, 3010 Old Clinic Blg, Chapel Hill, NC 27599, United States. Electronic address: kim_boggess@med.unc.edu.
authors.forename: Kim A
authors.initials: KA
authors.lastname: Boggess
authors.affiliation: Clinical Trials of America, 10 Coburg Rd., Eugene, OR 97401, United States. Electronic address: rbeyerlein@ctofa.com.
authors.forename: Richard
authors.initials: R
authors.lastname: Beyerlein
authors.affiliation: Advanced Research Associates, 5920 Saratoga Boulevard, Corpus Christi, TX 78414, United States. Electronic address: eubank@araresearch.com.
authors.forename: Charles
authors.initials: C
authors.lastname: Eubank
authors.affiliation: The University of Texas Medical School at Houston, 6431 Fannin, MSB 3.286, Houston, TX 77030, United States. Electronic address: nbist@aol.com.
authors.forename: Baha M
authors.initials: BM
authors.lastname: Sibai
keywords: Angiogenesis; Biomarker; Placental growth factor (PlGF); Preeclampsia; Triage PlGF test