What are the standard lab values for a woman on Bioidentical Hormone Replacement Therapy (BHRT)?

Standard Laboratory Values for Women on BHRT

For women on bioidentical hormone replacement therapy (BHRT), standard laboratory monitoring should include hormone levels, metabolic parameters, and safety markers, with interpretation based on physiologic reference ranges for premenopausal women in the luteal phase rather than postmenopausal values.

Hormone Level Monitoring

Estrogen Monitoring

• Estradiol (E2): Target physiologic reference ranges corresponding to the luteal phase of premenopausal women, typically 50-200 pg/mL 1
• Estriol (E3): When using BiEst formulations (80% estriol/20% estradiol), monitor to ensure adequate levels while maintaining the intended ratio 1
• Measurement should occur at baseline, 2 months after initiation, and then annually 1

Progesterone Monitoring

• Progesterone: Target luteal phase reference ranges for premenopausal women (typically 5-20 ng/mL) 1
• Progesterone levels below 6 nmol/L indicate anovulation and inadequate replacement 2
• Monitor at baseline, 8 weeks, and annually 1

Androgen Monitoring

• Testosterone: Normal range is <2.5 nmol/L; levels above this suggest excess 2
• DHEA-S: Age-specific ranges apply (age 20-29: <3800 ng/mL; age 30-39: <2700 ng/mL) 2
• Androstenedione: Should remain <10.0 nmol/L to rule out adrenal/ovarian pathology 2

Pituitary Hormones

• LH and FSH: Measure between cycle days 3-6 using average of three samples taken 20 minutes apart 2
  • LH/FSH ratio >2 suggests polycystic ovary syndrome 2
  • FSH >35 IU/L indicates ovarian failure 2
• Prolactin: Morning resting levels should be <20 μg/L (not post-ictal) 2

Metabolic and Safety Monitoring

Glucose Metabolism

• Fasting glucose: Should remain <7.8 mmol/L 2
• HOMA-IR (Homeostasis Metabolic Assessment of Insulin Resistance): Monitor at baseline and annually 1
• Glucose/insulin ratio: Values >4 suggest reduced insulin sensitivity 2

Lipid Profile

• Fasting triglycerides: Monitor at baseline, 2 months, and annually 1
• High-density lipoprotein and total cholesterol should be assessed as part of cardiovascular risk stratification 1

Hematologic Parameters

• Complete blood count (CBC): Monitor hemoglobin and platelet counts annually 1
• Hemoglobin: Should remain within female reference ranges (12-16 g/dL) 2
• Red blood cell indices are not significantly affected by estrogen-based BHRT, unlike testosterone therapy 2

Coagulation Factors

• Factor VII and Factor VIII: Monitor at baseline, 2 months, and annually 1
• Fibrinogen: Should be assessed as part of thrombotic risk evaluation 1
• Antithrombin III: Monitor annually 1
• PAI-1 (Plasminogen Activator Inhibitor-1): Assess at baseline and annually 1

Inflammatory Markers

• C-reactive protein (CRP): Monitor at baseline, 2 months, and annually 1
• Interleukin-6 (IL-6): Assess inflammatory status 1
• Matrix Metalloproteinase-9 (MMP-9): Monitor at baseline and annually 1
• Tumor Necrosis Factor-alpha (TNF-α): Evaluate immune signaling 1

Hepatic Function

• Liver enzymes (AST, ALT): Monitor as part of comprehensive metabolic panel 1
• Liver enzymes are mildly influenced by hormone therapy and values may shift 2

Renal Function

• Creatinine: Monitor as part of comprehensive metabolic panel 1
• Blood urea nitrogen (BUN): Assess renal function 1
• Electrolytes (sodium, potassium): Monitor for imbalances 1

Bone Health

• Insulin-like Growth Factor-1 (IGF-1): Monitor at baseline and annually 1
• Bone mineral density (DXA scan): Consider for patients with hypogonadism risk 3

Nutritional Status

• Albumin/total protein: Monitor every 6-12 months 2
• Transthyretin (prealbumin): Assess every 6-12 months 2
• Ferritin: Monitor yearly 2
• Vitamin D 25-OH: Assess annually 2

Monitoring Schedule

Initial Phase (First 8 Weeks)

• Baseline comprehensive hormone panel, metabolic panel, CBC, coagulation factors, and inflammatory markers 1
• Follow-up testing at 8 weeks to adjust dosing based on symptom relief and laboratory values 1

Maintenance Phase

• Annual monitoring of all hormone levels, metabolic parameters, hematologic indices, coagulation factors, and inflammatory markers 1
• Blood pressure and body mass index at every clinic visit 2

Critical Pitfalls to Avoid

• Do not use salivary hormone testing: Salivary measurements are not standardized and should be avoided in favor of serum testing 4
• Avoid postmenopausal reference ranges: Target physiologic luteal phase ranges rather than postmenopausal values to optimize symptom relief and safety 1
• Monitor endometrial thickness: In postmenopausal women with intact uteri, assess endometrial thickness to ensure progesterone adequately opposes estrogen 1
• Do not ignore cardiovascular biomarkers: Unlike conjugated equine estrogens with medroxyprogesterone acetate, bioidentical transdermal therapy shows favorable effects on hemostatic balance, but monitoring remains essential 1