Although von Willebrand disease (vWD) is the most common inherited bleeding disorder, hemophilia is the most well-known bleeding condition, and it too is typically inherited. There are different types of hemophilia, the most common being hemophilia A. Also known as classic hemophilia, hemophilia A is a deficiency of a protein called factor VIII, one of several proteins that our bodies need in order to form blood clots to heal wounds. Usually resulting from a genetic deficiency, specifically a problem with the gene that encodes factor VIII, hemophilia A is similar to another condition called hemophilia B, which is a deficiency of a different clotting protein called factor IX. Hemophilia A and hemophilia B are far more common in males than in females. The reason is that the genes for factors VIII and IX are located on the X chromosome. As a female, you have two chromosomes, whereas your father, your male partner, your sons and brothers, and all males have just one X chromosome. This means that if the gene for factor XIII or factor IX is missing or defective on one of your X chromosomes, you will still make normal clotting factor from the normal copy of the gene on your other X chromosome, unless your other X chromosome is inactivated. In contrast, if a boy has a hemophilia gene on his X chromosome, he will suffer hemophilia, he has no backup copy of the gene.
Classically, because of the fact that the defects in hemophilia A and B are on the X chromosome, geneticists have called these conditions “sex-linked”, or X-linked. Another way of saying this is that the condition is a dominant genetic disease in males and a recessive genetic disease in females. This means the females suffer the disease, only if they have a defective gene on both X chromosomes. However, in addition to being inherited, hemophilia can also develop as an acquired disease, meaning that it develops during adulthood (and not because you don’t have the genes to produce a clotting protein, such as factor VIII of hemophilia A). Acquired hemophilia results from your body producing chemicals that block the function of a clotting protein (factor VIII in the case of hemophilia A, factor IX in the case of hemophilia B). The biggest risk factor for the development of acquired hemophilia is having an autoimmune disease or cancer; however, pregnancy is also considered a risk factor, accounting for 8.4 percent of cases of acquired hemophilia.
Additionally, in recent years, hematologists and geneticists have come to realize that some female carriers of X-linked hemophilia can become symptomatic at some point in life. This recognition is similar to what is known about another blood condition called sickle cell disease –which like hemophilia is often described in basic biology courses as a classic example of a recessive disease in which people with one normal gene are just carriers, and yet it is possible for the carriers to get sick. This means that, if you are pregnant and have a hemophilia gene, the issue is not only that you can have a male child with hemophilia, but also that you could have the condition yourself. The most common symptoms of symptomatic carriers of hemophilia is menorrhagia (abnormally heavy menstrual bleeding). If menorrhagia is your only bleeding symptom and you are a carrier for hemophilia A, then your hemophilia is considered mild. In such a case, the condition is very likely to get better, not worse, as pregnancy progresses, since the production of factor VIII from your normal factor VIII gene increases in order to get you ready for delivery. Apart from menorrhagia, hemophilia can cause easy bruising as well as bleeding in the joints, muscles, and even in the brain.
Also important for women, there is another kind of hemophilia, called hemophilia C, which is genetic but not X-linked, so females can have it just as easily as males can. Essentially, due to a deficiency of still another clotting protein called factor XI, hemophilia C is usually more mild than hemophilia A and B. Often, it is called Jewish hemophilia, because it is much more common in Ashkenazi Jews than in any other group.
The main treatment for hemophilia A is infusion of factor VIII into your blood, while another treatment that can be given is called Desmopressin or DDAVP. These treatments are particularly good for hereditary hemophilia A, but they also can be helpful in some cases of acquired hemophilia A. In other cases of acquired hemophilia A and other types of acquired hemophilia, there are different strategies. One strategy is to give the woman recombinant porcine factor VIII. This means genetically engineered factor VIII of the kind that pigs make. Another strategy is to “bypass” the affected blood protein by giving you other clotting factors. The other strategy is to give agents that suppress the immune system. However, many immune suppressing agents cannot be given during pregnancy.
In severe cases of hereditary hemophilia B, the main treatment is called recombinant factor IX, whereas if you have hemophilia C (Jewish hemophilia), the main treatment is called tranexamic acid, given to prepare you for labor and delivery.
As for the period after giving birth, often hemophilia symptoms can get worse at this time if you have hemophilia A, or are a symptomatic carrier for it, since your body makes extra factor VIII as pregnancy advances, but then factor VIII production returns to normal. Although DDAVP can enter breast milk from the blood, the drug does not absorb well into the baby’s body when taken by mouth. For this reason, DDAVP is taken through the nose, or it is given to you by injection. Either way, you do not have to worry about your baby receiving it in your breast milk. If you are taking tranexamic acid, you should know that there is some concern about it getting into breast milk, but the concern is fairly low. Studies show that only small amounts will get into you milk, so if you really need this agent, most doctors will not use it as a reason for you to avoid breastfeeding.