Validated Research

The Endocrine Society anchors hypogonadal diagnosis near 264 ng/dL on two morning samples. The tool keeps that lab floor for flagging and layers a tighter functional target where most men feel and function best.

Free testosterone is computed with the Vermeulen equation from total T, SHBG, and albumin, which is the method endorsed over direct analog immunoassay.

SHBG is used to interpret free T and to inform dosing cadence. The optimal band is a clinical target, not a guideline cutoff.

The requirement to use a sensitive LC-MS/MS assay rather than standard immunoassay is well supported. The target band itself is a functional target.

Sustained elevation, especially above the level seen with medications or stress, prompts MRI per the Endocrine Society guideline.

Low inhibin B correlates with impaired spermatogenesis in cohort data. Used as a supportive marker, not a standalone diagnostic cutoff.

ASRM treats AMH and antral follicle count as the most reliable reserve markers and cautions that AMH predicts stimulation response, not natural conception. Age targets follow population nomograms.

Day 3 FSH interpretation follows ASRM. The tool also flags that day 3 estradiol above 50 can falsely suppress FSH.

The 2023 international guideline treats an elevated LH to FSH ratio as supportive context within Rotterdam criteria rather than a required diagnostic.

A mid-luteal value above roughly 3 ng/mL confirms ovulation in the literature. The tool uses a higher confirmatory threshold and a separate adequacy target.

Before labeling a pattern the tool prompts review of medications, stress, and timing, consistent with the Endocrine Society workup.

Matches the WHO 2021 sixth edition lower reference limit, defined as the 5th centile of men whose partners conceived within 12 months.

Both motility limits are taken directly from WHO 2021.

The 4 percent threshold reflects strict morphology criteria carried into WHO methodology.

DFI is layered in for unexplained infertility with normal standard parameters. Thresholds come from cohort and meta-analytic data, not a single guideline.

The pregnancy targets follow the American Thyroid Association trimester-specific guidance. The non-pregnant 0.5 to 2.0 band is a tighter functional target than the broad lab reference.

Targeting the upper half for the active hormone is a functional approach used to flag poor T4 to T3 conversion when TSH looks normal.

Detecting thyroid autoimmunity before conception is consistent with ATA guidance given the link to miscarriage and progression to overt hypothyroidism.

The ADA diagnostic cutoffs are preserved for flagging. The tool adds a tighter optimal band to surface early dysregulation within the normal range.

ADA thresholds define disease. The functional band sits below the prediabetes cutoff to flag metabolic drift earlier.

Fasting insulin is an early insulin resistance signal that often rises before HbA1c. The optimal band is a functional target, not a diagnostic cutoff.

The calculation follows the validated HOMA model. The optimal cutoff below 1.5 is a functional target on top of the validated formula.

Using ApoB as the primary atherogenic particle measure is guideline supported. The below 80 target reflects a primary prevention optimal rather than a treatment threshold.

An elevated triglyceride to HDL ratio is a well documented surrogate for insulin resistance and atherogenic particle size, used here as a screening flag.

The cardiovascular risk strata match the widely used hs-CRP cut points.

The tool uses a tighter preconception target because elevated homocysteine signals methylation and B vitamin status relevant to early pregnancy.

Deficiency and insufficiency cutoffs follow the Endocrine Society. The 50 to 70 band is a functional target above the sufficiency floor.

Deficiency cutoffs follow ACOG and CDC. The higher preconception target anticipates blood volume expansion and fetal iron demand.

Low normal B12 can be functionally deficient, so the tool prompts methylmalonic acid confirmation when borderline.

Prioritizing folate status before conception aligns with USPSTF folic acid guidance for neural tube defect prevention. RBC folate is preferred over serum for stores.

Transferrin saturation cutoffs follow CDC iron deficiency guidance and are interpreted alongside ferritin and inflammation.

Pregnancy anemia thresholds follow ACOG, which uses lower first and third trimester cutoffs than the second.

Because inflammation raises ferritin, the tool cross-checks ferritin against inflammatory context so deficiency is not masked.

The window model is taken directly from Wilcox 1995, with conception effectively limited to the days leading up to and including ovulation.

The day-by-day probability weighting follows the day specific clinical pregnancy curves in the foundational cohort studies.

Baseline dosing matches USPSTF and ACOG, with higher dosing reserved for a prior neural tube defect history.

The late pregnancy NSAID contraindication reflects the risk of premature ductus arteriosus closure and reduced amniotic fluid.