Inherited thrombophilia and pregnancy loss. Study of an Argentinian cohort

Thrombophilia might increase the risk of suffering from obstetric complications by adversely affecting the normal placental vascular function. Our aim was to study the distributions of five thrombosis-associated genetic variants: factor V Leiden, prothrombin G20210A, -675 4G/5G PAI-1, 10034C/T gamma fibrinogen and 7872C/T factor XI and the frequencies of the deficiencies of protein C, S and antithrombin in Argentinian patients with recurrent pregnancy loss (RPL) and, therefore, to analyse their association with the risk and timing of RPL and the risk of suffering other vascular obstetric pathologies.

We performed a case-control study that included 247 patients with idiopathic RPL (cases), 107 fertile controls and 224 subjects from general population (reference group). Cases were stratified according to the gestational time of the losses (early RPL, n = 89; late losses, n = 158; foetal losses, n = 107) and according to the type of vascular obstetric pathologies.

No differences were found in the distribution of the genetic variants among RPL group vs. control/reference group (p >.05). Similarly, no differences were observed in their distributions when analysing RPL patients stratified according to gestational times or vascular obstetric pathologies (p >.05), except for the factor V Leiden carriage in patients with foetal growth retardation vs. controls (11.8%, 4/34 vs. 1.9%, 2/107; p = .04) (OR = 7.11 [1.24-40.93], p = .03).

Factor V Leiden might have a significant impact on certain obstetric pathologies such as foetal growth retardation. The genetic variants, 10034C/T gamma fibrinogen and 7872C/T factor XI, associated with thromboembolic disease, would not have an impact on PRE.