title: First trimester maternal serum biochemical markers of aneuploidy in pregnancies with abnormally invasive placentation.
abstract: OBJECTIVE
  To examine whether differences exist in routine first trimester maternal serum screening analyte measurements between normal pregnancies, placenta praevia and abnormally invasive placentation (AIP).
  
  
  METHODS
  Multidisciplinary audit.
  
  
  METHODS
  Associated university teaching hospital with 9000 annual deliveries.
  
  
  METHODS
  Five hundred and sixteen pregnancies in total, including 344 normal controls, 17 with AIP and 155 placenta praevia cases.
  
  
  METHODS
  Comparison of maternal serum free βhCG and PAPP-A MoMs distribution in pregnancies with abnormally invasive placentation, placenta praevia and normal controls, after correcting for known confounding factors between October 2005 and September 2013. Data from a previously published first trimester AIP and biochemistry study were combined with our study data and compared in the above way to complete the analysis.
  
  
  METHODS
  Differences in first trimester maternal serum PAPP-A and free βhCG in AIP, placenta praevia, and normal pregnancies.
  
  
  RESULTS
  Median free βhCG MoM in the control group was 1.04, and 1.08 (P = 0.859) in the placenta praevia group compared with 0.81 in the AIP group (P = 0.06). Median PAPP-A MoM was 1.01 in the control group and 1.05 (P = 0.83) in praevia, compared with 1.22 in AIP cases (0.16). The combined AIP dataset gave an overall PAPP-A median MoM of 1.40, and free βhCG of 0.85. Both markers showed a significantly different distribution from controls (PAPP-A P = 0.002 and free βhCG P = 0.031).
  
  
  CONCLUSIONS
  There may be differences between first trimester maternal serum biochemical markers between normal pregnancies and those complicated by abnormally invasive placentation. If upheld, this may provide useful information for the early identification of abnormally invasive placentation. More studies are required.
authors: Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Queens Hospital, Romford, UK.
authors: O
authors: O
authors: Thompson
authors: Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Queens Hospital, Romford, UK.
authors: C
authors: C
authors: Otigbah
authors: Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Queens Hospital, Romford, UK.
authors: A
authors: A
authors: Nnochiri
authors: Department of Pathology, Queens Hospital, Romford, UK.
authors: E
authors: E
authors: Sumithran
authors: Prenatal Research Unit, Department of Clinical Biochemistry, King George Hospital, Goodmayes, UK.
authors: K
authors: K
authors: Spencer
mesh_terms: D000328:Adult; D000782:Aneuploidy; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D062145:Maternal Serum Screening Tests; D010921:Placenta Accreta / Q000097:blood / Q000175:diagnosis*; D010923:Placenta Previa / Q000097:blood / Q000175:diagnosis; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood*; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism*; D011446:Prospective Studies
chemical_list: D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; D011266:Pregnancy-Associated Plasma Protein-A; C579283:PAPPA protein, human
keywords: Abnormally invasive placentation; PAPP-A; aneuploidy; first trimester; free βhCG; placenta praevia