Welcome to period.com - Information on Online Pregnancy Test And Teen

LAS VEGAS -- There are six key thrombogenic mutations to be concerned about in pregnant patients, Dr. Charles Lock-wood said at the Fifth World Congress on Controversies in Obstetrics, Gynecology, and Infertility.

These include:

* Factor V Leiden mutation. About 80% of women with activated C-reactive protein resistance have this mutation. Both men and women with factor V Leiden mutation face a 30% lifetime risk of venous thromboembolism (VTE), and the prevalence in Europeans ranges from 5% to 15%. The prevalence of the mutation in the United States is about 5%, said Dr. Lockwood, who chairs the department of obstetrics, gynecology, and reproductive sciences at Yale University, New Haven.

About 40% of VTE events in pregnancy are caused by factor V Leiden mutation. Women with the mutation face a 10-fold increased risk of VTE during pregnancy.

However, this risk remains low in asymptomatic heterozygotes, at 0.2%, whereas the risk is far higher in homozygotes, at 16%-17%.

* Prothrombin gene mutation. Patients with this mutation also face a 30% lifetime risk of VTE; the prevalence is 2%-3%.

About 17% of VTE events in pregnancy are caused by the prothrombin gene mutation, and those who have it face a 15-fold increased risk of VTE during pregnancy. The risk of VTE in heterozygotes is just 0.5%, but the risk in homozygotes is 15%.

"These folks need anticoagulation therapy during pregnancy and anticoagulation post partum." Dr. Lockwood said. "If you're unlucky enough to have both the factor V Leiden and the prothrombin gene mutation--that is, a compound heterozygote--the risk of VTE is about 4%. [Such women] probably don't need anticoagulation during pregnancy, but they probably should get it post partum."

* Hyperhomocysteinemia. This condition "is probably the most discussed of all these mutations, but it increases the risk of VTE only 1.5-fold.

The prevalence of hyperhomocysteinemia in the general population is unknown. It can be caused by a mutation in cystathionine [beta]-synthase, which occurs in 0.3%-1.4% of the population, or by a thermolabile variant mutation in methylene tetrahydrofolate reductase (MTHFR). Studies have shown that about 12% of Europeans are at risk for the MTHFR mutant, "but the actual prevalence of hyperhomocysteinemia is far lower," he said. "It's easy to treat. You give 4-5 mg of folic acid a day, and most patients improve."

* Antithrombin deficiency. Patients with this deficiency face a 70%-90% lifetime risk of VTE. While the prevalence is low, at about 1 in 3,000, it's so thrombotic that it accounts for 2%-20% of VTE in pregnancy. "The literature is very disparate in this area, but the point is, even if it's 2%, it suggests that it's an incredibly thrombogenic disorder. This is a big deal," he said.

* Protein C deficiency. Patients with this deficiency face a 30% lifetime risk of VTE. The prevalence ranges from 0.2% to 0.5%, and it accounts for 10% of VTE cases in pregnancy. The risk of VTE during pregnancy is 4%. "That probably is not high enough to recommend heparin during pregnancy if they don't have any other risk factor," Dr. Lockwood said. "But if they do have other risk factors. I might treat these folks during pregnancy."

* Protein S deficiency. These patients face a 30% lifetime risk of VTE. The deficiency accounts for about 10% of VTE in pregnancy, and those who have it face about a 20-fold increased risk of VTE. The risk of VTE during pregnancy is 4%.

BY DOUG BRUNK

San Diego Bureau