National Institute of Child Health and Human Development
Maternal Fetal Medicine Units Network

A Prospective Observational Study of Women with
Factor V Leiden Mutation in Pregnancy

Related Publications & Presentations

Objective

To determine the incidence of pregnancy-related thromboembolism in women carrying the factor V Leiden mutation

Conclusion

Among women with no history of prior thromboembolic events, maternal heterozygous carriage of the FVL mutation is associated with a low risk of pregnancy-related venoustion is thromboembolism. Neither universal prenatal screening for the FVL mutation, nor treatment of the low-risk carrier during pregnancy is indicated.reatment of the low-risk carrier during pregnancy is indicated.

Clinical Centers

Magee Womens, Tennessee, Alabama, Wayne State, Cincinnati, Bowman Gray, Chicago, Ohio State, U of Miami, Texas-Dallas, Texas-San Antonio, Utah, Thomas Jefferson

Major Eligibility Criteria

• Less than 14 weeks gestation
• Singleton pregnancy
• No prior thromboembolism
• No heparin therapy in current pregnancy
• Informed consent

Design Type

• Observational cohort

Sample Size

• Goal = 5,000 patients

Outcome Measures

• Primary:
• Pregnancy-related thromboembolism in women with FVL
• Secondary:
• Preeclampsia
• Abruption
• Second trimester fetal death
• Neonatal morbidity and mortality

Timetable

• Enrollment: 02/2000-04/2001
• Data Collection: 02/2000-02/2002
• Closeout/Final Analysis: 02/2002-06/2002