title: Anticoagulation Regimens During Pregnancy in Patients With Mechanical Heart Valves: A Systematic Review and Meta-analysis.
abstract: Managing anticoagulation in pregnant women with mechanical heart valves remains challenging. Our aim was to evaluate the effectiveness and safety of 4 regimens in these women.
  
  
  
  Relevant studies published before June 2015 were collected in several databases and analyzed with RevMan version 5.3 and SPSS version 19.0. Four regimens were defined as follows: a regimen of a vitamin K antagonist (VKA) throughout pregnancy; a heparin (H)/VKA regimen using VKAs except for unfractionated heparin (UFH) or low molecular weight heparin (LMWH) during 6-12 weeks of pregnancy; a LMWH regimen of adjusted LMWH doses throughout pregnancy; and a UFH regimen of adjusted UFH doses throughout pregnancy. The low warfarin dose in the VKA regimen was defined as 5 mg/d or less.
  
  
  
  Fifty-one studies comprising 2113 pregnancies in 1538 women were included. The rate of fetal wastage was significantly higher in the high warfarin dose subgroup than in the low dose one. Compared with the H/VKA regimen, the rate of maternal major thromboembolic event in the low-dose VKA regimen group was significantly lower, although the fetal outcomes were similar. Compared with the H/VKA regimen, the rate of fetal wastage in the LMWH regimen group was significantly lower, and the maternal outcomes were similar. The UFH regimen presented the worst maternal and fetal outcomes.
  
  
  
  In the absence of large prospective trials, this meta-analysis showed that the VKA regimen should be best for pregnant women with a low warfarin dose, and the H/VKA regimen might be reasonable for those with a high warfarin dose. The LMWH regimen could be used for those who refuse VKA.
authors.affiliation: Division of Cardiac Surgery, The First Affiliated Hospital of Sun-Yat-sen University, Guangdong, PR China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Division of Obstetrics and Gynecology, The First Affiliated Hospital of Jinan University, PR China.
authors.forename: Jin
authors.initials: J
authors.lastname: Fan
authors.affiliation: Division of Obstetrics and Gynecology, The First Affiliated Hospital of Jinan University, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Luo
authors.affiliation: Division of Cardiac Surgery, The First Affiliated Hospital of Sun-Yat-sen University, Guangdong, PR China.
authors.forename: Wen-Bo
authors.initials: WB
authors.lastname: Zhang
authors.affiliation: Division of Cardiac Surgery, The First Affiliated Hospital of Sun-Yat-sen University, Guangdong, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: Guangdong Cardiovascular Institute, Guangdong Academy of Medical Sciences, Guangdong General Hospital, PR China.
authors.forename: Yu-Bi
authors.initials: YB
authors.lastname: Lin
authors.affiliation: Division of Cardiac Surgery, The First Affiliated Hospital of Sun-Yat-sen University, Guangdong, PR China.
authors.forename: Shao-Hong
authors.initials: SH
authors.lastname: Ma
authors.affiliation: Division of Obstetrics and Gynecology, The First Affiliated Hospital of Jinan University, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.affiliation: Division of Cardiac Surgery, The First Affiliated Hospital of Sun-Yat-sen University, Guangdong, PR China.
authors.forename: Zhi-Ping
authors.initials: ZP
authors.lastname: Wang
authors.affiliation: Division of Cardiac Surgery, The First Affiliated Hospital of Sun-Yat-sen University, Guangdong, PR China.
authors.forename: Jing-Song
authors.initials: JS
authors.lastname: Ou
authors.affiliation: Division of Cardiac Surgery, The First Affiliated Hospital of Sun-Yat-sen University, Guangdong, PR China. Electronic address: himybox@126.com.
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000014:Abnormalities, Drug-Induced; D000028:Abortion, Induced; D000022:Abortion, Spontaneous; D000925:Anticoagulants / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D005260:Female; D006350:Heart Valve Prosthesis; D006493:Heparin / Q000627:therapeutic use; D006801:Humans; D008428:Maternal Mortality; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000517:prevention & control*; D050497:Stillbirth; D013923:Thromboembolism / Q000517:prevention & control*; D014812:Vitamin K / Q000037:antagonists & inhibitors
chemical_list: D000925:Anticoagulants; D014812:Vitamin K; D006493:Heparin