Strengths and Limitations
Due to the retrospective design, data collection was restricted to
available content on databases, which resulted in missing data for
various indices, limiting statistical comparison between the two groups.
Furthermore, we were unable to assess psychological comorbidities such
as EDs, depression and anxiety using scoring scales, which is the
preferred method of assessment in most other FHA studies. In the absence
of a psychological diagnosis, more subtle traits and behaviours may have
gone undetected in our study. We also recognise that concomitant PCOS
cannot be excluded in some women with FHA; in our study clinicians
suspected underlying PCOS in 14 women with FHA. Previous studies, have
demonstrated that PCOS-like abnormalities, including elevated
anti-Mullerian hormone and PCOM on ultrasound, may be an incidental
finding in up to 40% of women with FHA and 10% may have co-existing
PCOS.
11,12 Thus, some women with FHA and low a BMI may
represent a subgroup of “suppressed PCOS”, which may be uncovered with
weight gain and lifestyle changes, ensuing
hypothalamic-pituitary-ovarian (HPO) axis recovery. 16In an attempt to clarify this clinical dilemma, various retrospective
studies have demonstrated lower incidence of hyperandrogenism, lower
mean LH levels and sex hormone binding globulins (indicating insulin
resistance), in women with FHA and underlying PCOS.
17,18 There remains, however, a lack of adequately
powered, prospective trials to investigate to what extent parameters
such BMI, estradiol, LH and LH:FSH ratio, differ in this subgroup of
women with FHA. A strength of this study is our large sample of women
with FHA, compared to previous studies. Our study is one of few to
compare women with FHA to those with PCOS, rather than eumenorrheic
women.