title: Embryo implantation after assisted reproductive procedures and maternal thrombophilia.
abstract: OBJECTIVE
  Women undergoing assisted reproductive procedures, such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), fail to achieve pregnancy in approximately 70% of cases. Postulating that among the possible causes of failure of embryo implantation might be an impairment of the uteroplacental circulation due to hypercoagulability in the mother, we investigated the association between thrombophilia and failure to achieve pregnancy after IVF or ICSI.
  
  
  METHODS
  A case-control study was carried out in 234 women undergoing IVF or ICSI and in 234 women who, in the same period, conceived naturally. Thrombophilia due to mutations in genes encoding coagulation factor V (G1691A), prothrombin (G20210A), methylene-tetrahydrofolate reductase (C677T) and the presence of antiphospholipid antibodies was searched for.
  
  
  RESULTS
  The prevalence of factor V, prothrombin and methylene-tetrahydrofolate reductase mutations was similar in the 162 women who failed to achieve pregnancy after IVF or ICSI and in control women (5% and 2% for factor V G1691A, odd ratio 2.4, 95% CI 0.8-7.4; 3% and 6% for prothrombin G20210A, odds ratio 0.5, 95% CI 0.2-1.5; 19% and 20% for homozygous methylene-tetrahydrofolate reductase C677T, odds ratio 1.0, 95% CI 0.6-1.6). Nor was any association found when women who failed to achieve pregnancy were divided according to the total number of assisted reproductive procedures, age, type of procedure and cause of infertility. Antiphospholipid antibodies were not detected in any of the women.
  
  
  CONCLUSIONS
  This study provides no evidence for an association between maternal thrombophilia and failure to achieve pregnancy after assisted reproductive procedures. Routine anticoagulant treatment in women undergoing assisted reproductive procedures is not warranted.
authors.affiliation: A. Bianchi Bonomi Hemophilia and Thrombosis Center, IRCCS Maggiore Hospital, University of Milano, Via Pace, 9, 20122 Milano, Italy. martin@policlinico.mi.it
authors.forename: Ida
authors.initials: I
authors.lastname: Martinelli
authors.forename: Emanuela
authors.initials: E
authors.lastname: Taioli
authors.forename: Guido
authors.initials: G
authors.lastname: Ragni
authors.forename: Paolo
authors.initials: P
authors.lastname: Levi-Setti
authors.forename: Serena Maria
authors.initials: SM
authors.lastname: Passamonti
authors.forename: Tullia
authors.initials: T
authors.lastname: Battaglioli
authors.forename: Corrado
authors.initials: C
authors.lastname: Lodigiani
authors.forename: Pier Mannuccio
authors.initials: PM
authors.lastname: Mannucci
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D010064:Embryo Implantation; D005165:Factor V / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D009154:Mutation; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000235:genetics; D011247:Pregnancy; D011256:Pregnancy Outcome; D011516:Prothrombin / Q000235:genetics; D027724:Reproductive Techniques, Assisted; D019851:Thrombophilia / Q000150:complications* / Q000235:genetics
chemical_list: D005165:Factor V; D011516:Prothrombin; D000587:Oxidoreductases Acting on CH-NH Group Donors; D042965:Methylenetetrahydrofolate Reductase (NADPH2)