Recent Study Examines Fertility and FD/MAS

Many McCune-Albright syndrome (MAS) patients have questions and concerns about fertility. This is not surprising, since MAS is some combination of fibrous dysplasia (FD) bone lesions, cafe-au-lait birthmarks, and hormone imbalances. These hormone imbalances can often lead to problems with patients’ reproductive systems, especially problems like ovarian cysts. While there are ways to manage those imbalances, it’s understandable that those symptoms might concern a patient interested in fertility. 

There has not been much research on FD/MAS and pregnancy. However, a recently published study led by Dr. Alison Boyce of the National Institute of Dental and Craniofacial Research at the National Institutes of Health, examined this question more thoroughly. “Many patients had been told that pregnancy might be dangerous for patients with FD, and were fearful of getting pregnant,” explained Dr. Boyce, “However our sense from seeing many patients over the years is that pregnancy didn’t seem to have a negative impact on FD. So for this reason we wanted to take a closer look at how pregnancy affects FD/MAS.”

The study evaluated 39 women with FD/MAS who were enrolled in the NIH’s natural history study of the disease. Dr. Boyce and her colleagues at the NIH and Children’s National Health System evaluated Clinical, radiographic, and biochemical data of these women. Additionally, the women shared detailed histories of their menstrual and reproductive health. 

The results did not show a clear connection between poor skeletal outcomes and pregnancy, but did reveal other reproductive health issues that female patients should consider.

For example, 77% of these women experienced abnormal uterine bleeding due to ovarian cysts, and nine underwent hysterectomies for management of bleeding. Although 43% of the women experienced infertility, there were 25 pregnancies conceived without medical intervention by 14 different women. 

These women reported a mix of experiences regarding bone pain during their pregnancies, with 7 reporting no change in bone pain, 4 reporting an increase in bone pain, and 2 reporting a decrease in bone pain. No women had fractures or other FD-related problems during pregnancy.

“This study shows that gynecologic problems are an important part of MAS that women should be evaluated and treated for,” said Dr. Boyce. “MAS might make it more difficult for some women to become pregnant. However it’s clear that pregnancy is possible in women with MAS, and based on our best available evidence, pregnancy doesn’t seem to be dangerous for women with FD. I would encourage any woman with MAS who are having problems with abnormal periods, or who desire pregnancy, to make sure they are getting care from an experienced gynecologist”. 

The full research study can be found here. Anyone who is interested in the research regarding FD/MAS can reach out to via the Disease Support Concierge, where FDF staff will respond personally to help patients connect to and understand the latest research regarding FD/MAS.