Follow monitoring protocol during sex hormone induction
STEP 1 — Gather Information
Confirm patient has initiated sex hormone therapy, document gender identity, sex assigned at birth, date of hormone start, baseline Tanner stage, and review prior monitoring results if any.
STEP 2 — Rule In / Rule Out
Is the patient transgender male (assigned female at birth, identifies as male) or transgender female (assigned male at birth, identifies as female)? This determines sex-specific monitoring parameters.
STEP 3 — Classify or Stratify
Calculate time since last monitoring visit: if ≥3 months, anthropometry due; if ≥6 months, laboratory tests due; if ≥12 months, bone mineral density (BMD) due.
STEP 4 — Decide
Order indicated tests: for transgender males: hemoglobin/hematocrit, lipids, testosterone, 25OH vitamin D; for transgender females: prolactin, estradiol, 25OH vitamin D; plus anthropometry (height, weight, sitting height, blood pressure, Tanner stage) every visit; schedule BMD via DXA if interval met.
Clinical Guardrails / Mimics / Pitfalls
Do not omit sex-specific labs (e.g., prolactin in transgender females, hemoglobin/hematocrit in transgender males); avoid delaying BMD monitoring beyond 2 years; ensure vitamin D assessment in all patients; recognize that missed monitoring may miss early detection of polycythemia, dyslipidemia, or prolactinoma.
Concrete Clinical Example
A 16-year-old transgender male initiates testosterone therapy. At 4-month visit: anthropometry performed; labs not yet due (6-month interval). At 8-month visit: anthropometry and labs (hemoglobin/hematocrit, lipids, testosterone, vitamin D) ordered; BMD not due until 12 months.
Source: Endocrine Treatment of Gender-Dysphoric/Gender-Incongruent Persons: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2017, https://doi.org/10.1210/jc.2017-01658