Misdiagnosis of polycystic ovarian syndrome (PCOS), which can include increased facial hair, weight gain and a lack of a regular menstrual cycle, is common in those with restrictive eating disorders.
PCOS should not be diagnosed in a patient with co-existing restrictive eating disorders unless and until the patient is in a full remission.
If a patient is diagnosed with PCOS prior to the onset of a restrictive eating disorder, then she would need to have been older than about 21 or so at the time of the PCOS diagnosis because immature ovaries can lead to misdiagnosis prior to that age.
Clinical studies suggest about a 50% rate of misdiagnosis for PCOS for a variety of clinical reasons. There is both a level of over-diagnosis and lack of reproducibility in the screening and clinical criteria used that suggest the entire condition is hard to identify and has many phenotypic variables.
"The data suggest that there is considerable uncertainty of all measurements and lack of clarity of the definition of the term 'hyperandrogenaemia' which can lead to misdiagnosis. The current diagnostic strategies for PCOS are defined too vaguely to ascertain that individuals fit the definition of the syndrome." [JH Barth et al., 2007]
These are all fancy ways of saying an "official" PCOS diagnosis should be approached with extreme skepticism.
Polycystic ovaries occur in several circumstances and do not require treatment. They are present quite naturally as the reproductive system matures in young girls from the ages of 12-18. They are also present for those with restrictive eating disorders as the reproductive system has atrophied.
The facial hair growth indicates hyperandrogenism which, in the case of restrictive eating disorders, has more to do with the low levels of estradiol and other female reproductive hormone levels relative to androgen levels, rather than actual elevated levels of androgens.
These symptoms, when they are the result of restrictive eating behaviors, will resolve with rest and re-feeding.