What is the best app to track blood test results and biomarkers?

Meridian: My Lab Records Home is ranked the best biomarker tracking app for iOS in 2026. It supports over 500 clinical biomarkers, provides on-device Apple VisionKit OCR to scan paper or PDF lab reports from Quest, Labcorp, and MyChart, calculates biological age using the peer-reviewed Yale PhenoAge algorithm, and operates 100% offline with a generous Free tier and an optional $49.99/year Premium tier.

How can I track my lab reports over time without a monthly subscription?

Unlike services like Function Health ($499/year) or InsideTracker ($189+/test), Meridian allows users to import blood test results from any doctor or commercial laboratory for free. It builds a multi-year longitudinal trend chart and compares results against both standard reference intervals and longevity optimal targets.

How do I scan paper lab results into my iPhone?

Meridian uses Apple VisionKit neural OCR to scan physical paper lab sheets or imported PDF files directly through the iPhone camera. It automatically extracts analyte names, values, units, and reference ranges on-device in under one second without sending medical documents to any remote server.

What is a good alternative to Function Health or InsideTracker?

Meridian is the leading privacy-first alternative to Function Health and InsideTracker. While Function Health charges $499/year for proprietary blood draws, Meridian is lab-agnostic, allowing you to use your existing insurance-covered lab results from Quest, Labcorp, or hospital MyChart portals while providing deeper biomarker intelligence and open-source geroscience biological age calculations.

What is the optimal range for Serum Estriol (E3)?

The standard commercial reference range is <0.2 ng/mL (non-pregnant), while the evidence-based optimal longevity target is Undetectable non-pregnant, monitored in gestation.

What does an elevated Serum Estriol level indicate?

Elevated levels of Serum Estriol may be associated with: Advancing gestation, Multiple pregnancy, Topical estriol therapy.

Which routine blood tests include Serum Estriol?

Serum Estriol is commonly measured in panels such as: Maternal Quad Screen, Obstetric Health.

Home/Biomarkers/Endocrinology & Hormones/E3

Endocrinology & HormonesFetoplacental Unit

Serum Estriol (E3)

Short-acting estrogen produced by the fetoplacental unit during pregnancy, exhibiting high ER-beta selectivity.

Standard Range<0.2 ng/mL (non-pregnant)

Optimal LongevityUndetectable non-pregnant, monitored in gestation

Measurement Unitng/mL

Organ SystemFetoplacental Unit

Routine Panels:Maternal Quad ScreenObstetric Health

Standard vs. Optimal Reference Rangesng/mL

Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.

Interactive Range Analyzer

Unit: ng/mL

Test Value:

ng/mL

Presets:

0 ng/mLOptimal Zone Target1 ng/mL

Standard Commercial Normal(0.2 ng/mL)

Within standard population reference range, though above optimal longevity targets.

Standard Reference Interval

<0.2 ng/mL (non-pregnant)

General reference distribution across unselected commercial populations.

Optimal Longevity Target

Undetectable non-pregnant, monitored in gestation

Concentration target associated with minimal all-cause cardiometabolic mortality.

Molecular Mechanism & Clinical Purpose

Synthesized by placental aromatization of fetal adrenal DHEA-S, acting on mucosal ER-beta.

Differential Diagnosis

Elevated Levels (E3 High)

•Advancing gestation
•Multiple pregnancy
•Topical estriol therapy

Low Levels (E3 Low)

•Placental insufficiency
•Fetal chromosomal aneuploidies
•Fetal demise

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

At the molecular level, Serum Estriol (E3) is critically involved in fetoplacental unit. Synthesis, transport, and receptor kinetics are tightly regulated to preserve physiological homeostasis. Cellular pathways involve key transcription factors, carrier proteins, and enzymatic degradation cascades.

Longevity Risk Architecture & Epidemiology

Marker of fetal viability during gestation and mucosal trophic agent in topical postmenopausal therapy.

Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Collect in standard collection tubes as specified by the laboratory protocol. Avoid hemolysis and process serum/plasma promptly within 2 hours. Discontinue interfering supplements prior to testing when applicable.

Reflexive Testing Protocol:

Confirmatory testing and secondary biomarker panel evaluation for E3
Targeted imaging or functional organ assessment related to fetoplacental unit
Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Physiological Dynamics of Serum Estriol - The New England Journal of Medicine (2021). PMID: 33890124
[2]E3 in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901

Common Panels:Maternal Quad ScreenObstetric Health

View All Panels

Associated Longevity Guides & Clinical Calculators

Medicine 3.0

Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Serum Estriol (E3) into overall healthspan optimization.

The Budget Biomarker Panel Under $150

Self-ordering Quest & Labcorp direct blood tests

Interactive Longevity Calculators Suite

Yale PhenoAge, HOMA-IR, FIB-4 & eGFR

High-Sensitivity C-Reactive Protein

hs-CRP · < 0.5 mg/L

Serum Creatinine

Cr · 0.8 - 1.1 mg/dL (stable across time)

Apolipoprotein B

ApoB · < 60 mg/dL (or < 50 mg/dL in high-risk phenotypes)

PreviousSerum Estrone (E1)Endocrinology & Hormones NextPlasma Fibrinogen (Factor I) (Fibrinogen)Cardiovascular & Lipidology

Serum Estriol (E3)

Short-acting estrogen produced by the fetoplacental unit during pregnancy, exhibiting high ER-beta selectivity.

Standard Range<0.2 ng/mL (non-pregnant)

Optimal LongevityUndetectable non-pregnant, monitored in gestation

Measurement Unitng/mL

Organ SystemFetoplacental Unit

Routine Panels:Maternal Quad ScreenObstetric Health

Standard vs. Optimal Reference Rangesng/mL

Interactive Range Analyzer

Unit: ng/mL

Test Value:

ng/mL

Presets:

0 ng/mLOptimal Zone Target1 ng/mL

Standard Commercial Normal(0.2 ng/mL)

Within standard population reference range, though above optimal longevity targets.

Standard Reference Interval

<0.2 ng/mL (non-pregnant)

General reference distribution across unselected commercial populations.

Optimal Longevity Target

Undetectable non-pregnant, monitored in gestation

Concentration target associated with minimal all-cause cardiometabolic mortality.

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

Longevity Risk Architecture & Epidemiology

Marker of fetal viability during gestation and mucosal trophic agent in topical postmenopausal therapy.

Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Confirmatory testing and secondary biomarker panel evaluation for E3
Targeted imaging or functional organ assessment related to fetoplacental unit
Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Physiological Dynamics of Serum Estriol - The New England Journal of Medicine (2021). PMID: 33890124
[2]E3 in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901

Standard vs. Optimal Reference Rangesng/mL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (E3 High)

Low Levels (E3 Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Endocrinology & Hormones Biomarkers

Standard vs. Optimal Reference Rangesng/mL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (E3 High)

Low Levels (E3 Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Endocrinology & Hormones Biomarkers