Rituxan and Pregnancy
When Rituxan (rituximab) was given to pregnant monkeys during animal studies, the medication caused low levels of a certain type of white blood cell in the newborns. As a result, the FDA considers Rituxan a pregnancy Category C medication, which means it may not be safe for women who are expecting. However, it can still be prescribed if the benefits outweigh the risks.
Can Pregnant Women Use Rituxan?
- Non-Hodgkin's lymphoma
- Chronic lymphocytic leukemia
- Rheumatoid arthritis
- Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA).
At this time, it is unclear whether this medication is safe for use during pregnancy.
What Is Pregnancy Category C?
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category C is given to medicines that have not been studied in pregnant humans, but do appear to cause harm to the fetus in animal studies.
In addition, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating.
It is important to understand that a pregnancy Category C medicine may be given to pregnant women if the healthcare provider believes that the benefits to the woman outweigh any possible risks to the unborn child.
When given to pregnant monkeys, Rituxan did not increase the risk of any birth defects. However, it did cause low B lymphocytes (a type of white blood cell) in the newborns. This is expected, given the way Rituxan works. Within six months after birth, the number of B cells normalized.
Although Rituxan has not been systematically studied in pregnant humans, there have been a few reported cases of human exposure during pregnancy. These cases do not suggest any association between Rituxan and birth defects, miscarriages, and other problems.
In some cases, low B lymphocytes were seen in the newborns, which normalized within a few months after birth. It is important to note that "infusion reactions," which are common with Rituxan, can be especially dangerous in pregnant women, as the very low blood pressure (hypotension) that often occurs with such reactions can cause low blood flow and oxygen to the baby.