How Do I Know If I Have POTS with Endometriosis or Pelvic Pain?

April 26, 2026

How Do I Know If I Have POTS — Especially If I Already Have Endometriosis or Pelvic Pain?

You don’t need a tilt table test. Here’s how to find out, with a downloadable tracker you can fill out right on your phone.

If you’re reading this, you probably already know something is wrong. Maybe you stand up and your heart pounds. Maybe the room tilts when you get out of bed. Maybe you can’t walk through a grocery store without sitting down. Maybe you’ve been told it’s anxiety, or that you just need to drink more water. And maybe you also have endometriosis, chronic pelvic pain, painful periods, or a history of failed pelvic surgery — and no one has connected the dots.

You’re not imagining it. The condition you may be looking for is POTS — Postural Orthostatic Tachycardia Syndrome — and it is dramatically under-diagnosed in patients with endometriosis and chronic pelvic pain.

The good news: you do not need a tilt table test to find out. A simple, validated, ten-minute test called the NASA Lean Test can be done in any clinic, and a structured home version can give you and your physician real data to work with.

This article walks you through (1) what POTS actually is, (2) why it shows up so often in the patients we see at ESSI, (3) why a tilt table is not required for diagnosis, (4) how the NASA Lean Test is performed, and (5) how to use our downloadable patient tracker to bring objective measurements to your next appointment.

What Is POTS?

POTS is a form of dysautonomia — a disorder of the autonomic nervous system — in which standing upright produces an abnormal cardiovascular response. The diagnostic criteria most autonomic specialists use are straightforward:

A sustained heart rate increase of at least 30 beats per minute (bpm) within 10 minutes of moving from supine to standing in adults.
A heart rate increase of at least 40 bpm in adolescents (ages 12–19).
Symptoms of orthostatic intolerance during the test — lightheadedness, palpitations, tremor, brain fog, visual changes, nausea, or fatigue.
In the absence of orthostatic hypotension (a drop in systolic BP of ≥20 mmHg or diastolic BP of ≥10 mmHg in the first 3 minutes).

In short: the heart races when the patient stands up, and standing reproduces the symptoms they live with every day.

Why POTS Shows Up So Often in Endometriosis and Pelvic Pain

At ESSI, we see this pattern repeatedly: a patient comes in for endometriosis or chronic pelvic pain and — once we ask the right questions — also describes lightheadedness on standing, brain fog, palpitations, exercise intolerance, and crushing fatigue. This is not a coincidence. It is what the PARTS framework was built to explain.

PARTS stands for Pelvic Arterial and Venous Syndromes. But it is far more than a vascular concept. PARTS describes the pelvis as an integrated system in which three processes converge:

Vascular dysfunction — pelvic venous pooling, ovarian and iliac vein reflux, May-Thurner compression, and pelvic varicosities.
Neurologic dysfunction — sensitization and entrapment of the pelvic nerves and autonomic pathways that pass through this region.
Inflammatory disease — endometriosis itself, with its fibrosis, adhesions, and neurovascular remodeling.

When these three processes overlap — and they very often do — the pelvis becomes a self-perpetuating loop of inflammation, congestion, and nerve sensitization. That is the PARTS pattern. And it does not stay confined to the pelvis.

The pelvis is the largest venous reservoir in the lower body. When pelvic venous return is compromised, the rest of the cardiovascular system has to compensate, and the autonomic nervous system gets pulled into the fight. That is one mechanism by which patients with PARTS develop the orthostatic, autonomic, and systemic symptoms we recognize as POTS.

The clinical implication: if you have endometriosis or chronic pelvic pain and you also have lightheadedness, palpitations, or fatigue on standing, screening for POTS is not optional. It is part of treating the whole patient. And it is far more accessible than most clinicians realize.

Why You Don’t Need a Tilt Table Test to Diagnose POTS

There is a persistent myth — still repeated by many clinicians — that POTS cannot be diagnosed without a tilt table. That is not true, and the consensus literature is clear on it.

The diagnostic criteria are based on heart rate and blood pressure, not on the table. The diagnostic threshold (≥ 30 bpm in 10 minutes with symptoms) is a hemodynamic finding. Any test that reliably measures supine-to-upright changes in heart rate and blood pressure across 10 minutes — with the patient minimizing leg muscle activity — can capture it.
Standing tests perform comparably to tilt for POTS detection. Head-to-head studies have shown that a 10-minute standing protocol identifies the great majority of POTS cases that a 10-minute tilt would identify. In one widely cited comparison, the 30-bpm criterion had similar sensitivity on both tests, while the standing test actually had better specificity — fewer healthy people are incorrectly labeled as having POTS. Longer tilt durations (30 minutes) are notorious for producing false positives in healthy controls.
Tilt tables are not universally available. Tilt table testing requires a motorized table, continuous monitoring, an autonomic lab, and trained personnel. Most community hospitals don’t have one. Insurance authorization is frequently denied. Patients can wait months. None of this is necessary to identify the majority of patients who need treatment.
Tilt is not benign. Patients with severe POTS often experience near-syncope or syncope during tilt. The test is uncomfortable, frightening, and — for some patients — triggers a flare that lasts days. A 10-minute lean test in a controlled office environment is a much gentler first-line evaluation.

Tilt table testing remains valuable when the diagnosis is unclear, when neurally mediated syncope is the primary question, or when autonomic specialists need additional data. But for most patients, it is not the first — and certainly not the only — way to confirm POTS.

What Is the NASA Lean Test?

The 10-Minute NASA Lean Test (NLT) is a standardized passive-stand test, originally derived from protocols NASA developed to study orthostatic deconditioning in astronauts returning from spaceflight. It was refined for clinical use and standardized by the Bateman Horne Center as a point-of-care tool for evaluating orthostatic intolerance in ME/CFS, long COVID, and POTS.

The test is called a “lean” test because the patient stands with their shoulder blades resting against a wall and their feet placed about six inches out from the baseboard. This posture deliberately reduces the calf muscle pump — the squeezing of leg muscles that normally helps push blood back to the heart — so the test approximates the passive conditions of a tilt table without the table itself.

All it requires is a wall, an exam table, a blood pressure cuff, a pulse oximeter or heart rate monitor, a watch, and a recording sheet. That’s it.

How the NASA Lean Test Is Performed

Before the Test

Preparation depends on the goal. For a new diagnostic evaluation, the patient should not be on treatments that mask orthostatic intolerance, because those treatments can hide a positive result. With clinician guidance, the following preparation is typical:

Stop extra fluid loading and added sodium for 24 hours before the test.
Do not wear compression garments during the test.
Hold or taper medications that influence the test — only under direct medical supervision. These commonly include midodrine, fludrocortisone, beta blockers, stimulants, tricyclic antidepressants, SNRIs, and tizanidine.

Important: no medication should be stopped without explicit instructions from the prescribing clinician. After the test, treatments should be resumed immediately.

If the goal is instead to assess how well current treatment is working, the patient should remain on their full regimen and perform the test mid-day on their usual fluids, sodium, compression, and medications.

The Test Itself

Supine rest. The patient lies flat on an exam table for at least 10 minutes. Heart rate and blood pressure are recorded at minute 1 and minute 2 of the rest period.
Move to standing. The patient stands and leans against a wall: shoulder blades touching the wall, heels approximately six inches out from the baseboard. Arms are relaxed at the sides.
Capture vitals immediately. Heart rate and blood pressure are recorded at minute 0 of standing.
Continue for 10 minutes. Heart rate and blood pressure are recorded every minute for 10 full minutes.
Record symptoms throughout. At each measurement, the patient describes any symptoms — lightheadedness, brain fog, palpitations, nausea, visual changes, tremor, leg pooling, or anything that mirrors their day-to-day experience.
Stop early if needed. If the patient feels they are about to faint, the test should be ended immediately. The goal is information, not a syncopal episode.

Important Reminders During the Test

Stay relaxed. Tensing the legs activates the muscle pump and falsely improves the result.
Limit movement. Avoid shifting weight, fidgeting, or rocking. Keep arms loose at the sides.
Limit conversation. Talking can affect breathing and heart rate.
Speak up. Vocalize symptoms as they happen so they can be recorded against the corresponding vitals.
Never test alone. Patients with known or suspected POTS can faint. A clinician or a trusted person trained to assist must be physically present.

How to Interpret the Results

Diagnosis is based on the change in heart rate and blood pressure between supine baseline and standing, combined with reproduction of the patient’s symptoms.

POTS

Sustained heart rate increase of ≥ 30 bpm (or ≥ 40 bpm in adolescents) within 10 minutes of standing.
Or, a standing heart rate exceeding 120 bpm.
Without orthostatic hypotension.
With reproduction of orthostatic symptoms.

Orthostatic Hypotension (OH)

A drop of ≥ 20 mmHg in systolic blood pressure, or ≥ 10 mmHg in diastolic blood pressure, within the first 3 minutes of standing.

A note on numbers without symptoms: A heart rate that meets the threshold but is not accompanied by symptoms is not, by itself, a POTS diagnosis. Healthy individuals — especially after deconditioning, illness, or in hot environments — can show transient tachycardia on standing. The combination of objective hemodynamic change and reproducible, characteristic symptoms is what makes the diagnosis.

Use Our Downloadable NASA Lean Test Tracker

Many of our patients arrive with chronic, fluctuating symptoms and no objective record of how their body responds to standing. A single test on a single day rarely captures the variability of POTS.

To help, ESSI has created a downloadable NASA Lean Test tracking sheet you can use across multiple test days and bring to your appointment. The tracker comes in two versions:

A printable PDF you can print and fill in by hand.
A fillable PDF you can complete on your phone, tablet, or computer — tap any cell to type, tap any checkbox to toggle it, and the summary table at the end auto-calculates your baseline averages, peak values, and change from baseline as you go. The fillable version also generates a plain-language description of the pattern in your numbers (not a diagnosis) to share with your clinician.

NASA Lean Test Patient Tracker Fillable

Tip: Use the fillable version on your phone

Most patients find it easier to fill the tracker on a phone in real time than to write while standing against a wall. For the best experience on iPhone or iPad, open the fillable PDF in Files or Books. On Android, open it in the free Adobe Acrobat Reader app. Once you’re done, use your phone’s share menu to email the completed tracker to your clinician.

Used over several test days — ideally on good days and bad days, before and after treatment changes — the tracker gives clinicians something the tilt table never can: a longitudinal picture of how this individual patient responds to standing in their real life.

The Bottom Line

If you’re asking yourself “How do I know if I have POTS?” — especially if you already live with endometriosis, pelvic pain, or unexplained pelvic congestion — you do not need to wait for a tilt table. The 10-Minute NASA Lean Test is a validated, accessible alternative.

With the downloadable ESSI tracker and a clinician willing to supervise, you can gather the data your body has been trying to show you all along. And if you do test positive, that information matters. POTS that emerges in a PARTS context is not a separate problem from your pelvic disease — it is part of the same story. Recognizing it is the first step toward treating the whole patient, not just the individual specialty.

Medical Disclaimer

This article is for educational purposes only and is not a substitute for individualized medical advice. The NASA Lean Test should not be performed alone. Patients should never stop or change medications without explicit guidance from their prescribing clinician. If you suspect you have POTS or another form of dysautonomia, please consult a qualified physician. The 10-Minute NASA Lean Test protocol is adapted from materials developed and standardized by the Bateman Horne Center (batemanhornecenter.org).

Selected References

Bateman Horne Center. The 10-Minute NASA Lean Test: Patient Instructions (June 2022).
Bateman Horne Center. The 10-Minute NASA Lean Test: Clinician Instructions (June 2022).
Lee J, Vernon SD, Jeys P, et al. Hemodynamics during the 10-minute NASA Lean Test: evidence of circulatory decompensation in a subset of ME/CFS patients. J Transl Med. 2020;18:314.
Plash WB, Diedrich A, Biaggioni I, et al. Diagnosing postural tachycardia syndrome: comparison of tilt testing compared with standing haemodynamics. Clin Sci (Lond). 2013;124(2):109–114.
Roma M, Marden CL, Rowe PC. Passive standing tests for the office diagnosis of postural tachycardia syndrome. Fatigue: Biomedicine, Health & Behavior. 2018;6(4):179–192.
Vernon SD, Hartle M, Sullivan K, et al. Orthostatic challenge causes distinctive symptomatic, hemodynamic and cognitive responses in long COVID and ME/CFS. Front Med. 2022;9:917019.
Stewart JM. Common syndromes of orthostatic intolerance. Pediatrics. 2013;131(5):968–980.