Uso de la heparina para prevenir pérdidas gestacionales
Written by:Thrombophilia is directly related to gestational failures. The doctor. Fariñas, expert in Hematology , talks about the use of heparin in patients with numerous abortions, more than 35 years and thrombophilia.
Why does the gynecologist refer women with fertility problems to the hematologist?
To perform a thrombophilia study. Thrombophilia is the predisposition to venous thrombosis. Pregnancy is a procoagulant situation and in vascular complications of pregnancy is even more intensified. Thrombophilia would increase it even more. The studies have fundamentally studied the genetic venous thrombophilia, fundamentally the mutation of Factor V Leiden and the mutation of the prothrombin gene. In 2005, a meta-analysis of control cases found a relationship between different thrombophilias and different types of gestational losses. Since then there has been controversy. In 2014 an important objective study that women who have had at least 3 abortions, if they also have the Factor V Leiden mutation or the mutation of the prothrombin gene have a higher risk of having a fetal loss of more than 10 weeks. On the other hand, anticardiolipin antibodies are seen in 15% of women who have had repeat abortions.
What is the use of heparin to prevent gestational failures?
Heparin could improve this procoagulant situation but not only from week 10 or 12 when the uteroplacental circulation is established, but from the beginning of pregnancy, from the moment of implantation where haemostasis is fundamental. Besides, heparin has multiple effects to favor implantation and to favor the development of trophoblast and trophoblastic invasion. Has the utility of heparin been proven to prevent repeat miscarriages? No, it's not shown in women who do not have thrombophilia. The reason is that randomized trials have not had a sufficient number of patients, chromosomal alterations have not been studied and in many of them heparin could not be applied since the beginning of pregnancy. At this time a 35-year-old woman, under 35 with two abortions, it is not clear that heparin will benefit but women over 35 years with at least 2 abortions there is not enough evidence. In women with thrombophilia, randomized trials have not been conclusive because heparin has been applied since week 10 of gestation. However, very important observational studies with many patients do find heparin useful when heparin is applied from the beginning of pregnancy.
Is thrombophilia related to implantation failures?
In 2006, Kubland found a relationship between implantation failure and thrombophilia. Subsequently there has been much controversy. The meta-analyzes of control cases find Factor V Leiden and anticardiolipin antibodies, so many authors suggest that the thrombophilia study be performed in women who have had at least 3 implantation failures. Regarding the usefulness of heparin, randomized trials have found that women with at least 3 implantation failures result in pregnancy at term is 78% higher than if heparin is not used, but the number of participants is small. In important but non-randomized trials, a benefit to heparin is found, but the number of participants is small and it is therefore suggested that urgent randomized studies be conducted.. But randomized trials for women with repeat abortions have taken 10 or 12 years, so we considered whether a 37-year-old woman who has not had children, who has had 3 implantation failures, can wait to perform these randomized trials or heparin can be used at a prophylactic dose that may reduce the risk of thrombosis and may help you achieve pregnancy.
