The 5, 10 methylenetetrahydrofolate reductase C677T mutation and risk of fetal loss: a case series and review of the literature

We report a series of 8 patients with this issue and review the current literature.8 patients (3 of whom were actively pregnant) were referred with histories of spontaneous fetal loss; hypercoaguability work-ups revealed each were homozygous for the MTHFR C677T mutation without other thrombophilias.In the 3 women who have conceived, treatment with LMW heparin during pregnancy led to two full-term births and one additional pregnancy without complication. For the 5 who have not, we recommended treatment with LMW heparin upon conception.We provide evidence to support the relationship between MTHFR C677T mutations and recurrent fetal loss, and to suggest that anticoagulation of these patients during pregnancy can lead to a successful pregnancy outcome.There is growing evidence that thrombophilia defects can impact pregnancy outcomes. It is already well-known that the acquired thrombophilia of the antiphospholipid syndrome, seen with lupus anticoagulant and/or anticardiolipin antibody seropositivity, is strongly associated with recurrent fetal loss[1]. In the literature, various hereditary thrombophilias such as activated protein C resistance, the factor V leiden mutation (both homozygosity and heterozygosity), the prothrombin G20210A mutation, protein S deficiency, the methylenetetrahydrofolate reductase (MTHFR) C677T mutation, hyperhomocysteinemia, or combinations of the above disorders have also been linked to pregnancy loss at varying stages of gestation [2,3]. Yet because many of the published case series and meta-analyses describe conflicting results, the relationship between a MTHFR mutation and recurrent miscarriages remains confusing. We present eight cases from our institution that may well represent the impact of homozygosity of the MTHFR C677T mutation on early pregnancy loss.Eight women presented within a span of three months to our institution with histories of one or more miscarriages after the 10th week of gestation. These women were referred to our progr