Endo Fha Bmd Pcos Fha

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name: endo-fha-bmd-pcos-fha
description: This skill recommends obtaining a baseline BMD measurement by DXA in adolescents or women with functional hypothalamic amenorrhea (FHA) and concurrent polycystic ovary syndrome (PCOS) who have six or more months of amenorrhea, and earlier if there is history or suspicion of severe nutritional deficiency, other energy deficit states, or skeletal fragility. Use when a clinician states, “She has PCOS and no periods for seven months—let’s get a DXA,” or similar triggers such as “Check BMD in PCOS+FHA after six months amenorrhea” or “Order DXA sooner due to low weight.”
---

# Baseline BMD monitoring in patients with FHA and underlying PCOS

## STEP 1 — Gather Information
Confirm diagnosis of FHA (exclusion of organic causes) and PCOS (per Rotterdam criteria), assess duration of amenorrhea, evaluate for risk factors (weight/BMI <18.5 kg/m2, recent weight loss, excessive exercise, disordered eating, prior fractures, low trauma fracture history), and obtain baseline labs (CBC, CMP, TSH, prolactin, LH/FSH, estradiol, AMH, testosterone/DHEA‑S if hyperandrogenism suspected). If FHA and PCOS are confirmed, proceed to assess amenorrhea duration and risk factors.

## STEP 2 — Rule In / Rule Out
Rule in: ≥6 months of amenorrhea **OR** any high‑risk factor (history/suspicion of severe nutritional deficiency, other energy deficit state, or skeletal fragility). Rule out: <6 months of amenorrhea **and** absence of all high‑risk factors. If ruled in, move to classification; if ruled out, defer DXA and reassess in 3 months or sooner if clinical changes occur.

## STEP 3 — Classify or Stratify
Classify as **routine baseline** (≥6 months amenorrhea without high‑risk features) versus **early baseline** (<6 months amenorrhea with any high‑risk factor). Both categories indicate a DXA is warranted, but timing differs.

## STEP 4 — Decide
For routine baseline: order DXA (lumbar spine, hip, and/or whole body) now, report Z‑score (prefer Z‑score over T‑score in premenopausal women), and repeat in 1–2 years if Z‑score remains ≤‑1.0 or sooner if clinical deterioration. For early baseline: order DXA immediately, repeat in 6 months to monitor change, and initiate aggressive nutritional/weight‑restoration interventions irrespective of DXA result.

## Clinical Guardrails / Mimics / Pitfalls
Do not order DXA before excluding pregnancy; do not use T‑score for interpretation in premenopausal patients; do not delay weight‑gain or nutritional rehabilitation pending DXA results; do not rely on DXA alone to diagnose PCOS or to exclude other causes of amenorrhea; avoid repeat DXA sooner than 6 months unless a clinically significant change in bone health is suspected.

## Concrete Clinical Example
A 19‑year‑old woman with known PCOS presents with 8 months of amenorrhea, BMI 22 kg/m2, no disordered eating, weight‑stable, and no prior fractures. FHA is confirmed after exclusion of thyroid, prolactin, and anatomic causes. She meets the routine baseline criterion (≥6 months amenorrhea, no high‑risk factors). A DXA of lumbar spine and hip is ordered; the lumbar spine Z‑score is ‑0.8 and hip Z‑score is ‑0.4. Results are discussed, and repeat DXA is planned in 18 months while continuing lifestyle optimization.

**Source:** Functional Hypothalamic Amenorrhea: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2017, https://doi.org/10.1210/jc.2017-00131