How does the presentation of hemophilia A differ in females?

Updated: Jan 14, 2019
  • Author: Douglass A Drelich, MD; Chief Editor: Srikanth Nagalla, MBBS, MS, FACP  more...
  • Print
Answer

Because hemophilia is an X-linked, recessive condition, it occurs predominantly in males. Females usually are asymptomatic carriers. However, mild hemophilia may be more common in carriers than previously recognized. In 1 study, 5 of 55 patients with mild hemophilia (factor levels 5-50%) were girls. [19]

Females may have clinical bleeding due to hemophilia if any of the following 3 conditions is present:

  • Extreme lyonization (ie, inactivation of the normal FVIII allele in one of the X chromosomes) [20]

  • Homozygosity for the hemophilia gene (ie, father with hemophilia and mother who is a carrier, two independent mutations, or some combination of inheritance and new mutations)

  • Turner syndrome (XO) associated with the affected hemophilia gene


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!