EndoLoop | Diagnosing Endometriosis with a Prick of a Finger☝🏽🩸

“the doctor said I was making my pains up so I could miss school — it’s taken me 11 years to finally get a diagnosis”

“just got told I had heavy periods”

“when I go to A&E, they think that I might be a drug addict, and that I was making it [my pains] up

“the pain is like barbed wire wrapped around your insides and someone’s pulling it while at the same time an animal is trying to eat its way through you.”


There’s a disease that affects 11 in 100 women (11% of women!!!) where it feels like “someone’s getting a knife and just whipping it around on the inside”, making it more common than diabetes (10 in 100 people), however it does not have a cure and the average women gets diagnosed 8 years LATE.


Nathalie Zender, is my friend, Liesl Anggijono’s teacher and her endometriosis story represents that of millions, and we’re here to build a different storyline for those that follow.

Here’s her story

^Nathalie❤ Thank you for letting us share your story!

She started her period at 13. Her symptoms included severe cramps, bloating, heavy flow, body aches, nausea, fainting, vomiting, fever, loss of appetite, intense mood swings, depression, insomnia, and social anxiety.

At age 14, she says, “my mom finally had enough and took me to a doctor to see if my menstrual cycle and side effects were normal. The doctor immediately prescribed me birth control to reduce the symptoms without mentioning any other options. It felt as if my suffering was insignificant and birth control was the most convenient solution for the doc.”

“Between the ages of 14–28 (now), I have tried 7 different birth control pills because of their negative side effects. Some would relieve my cramps at the expense of my mental health. It seemed as though I had to sacrifice one thing for another. Until I finally found one that seemed to offer me the best balance between mental and physical health of the pill: Zinnia.”

Fast forward to now, at the age of 28, she was diagnosed with Deep Vein Thrombosis (DVT) that was likely caused by the prolonged use of oral birth contraceptives.

Most blood clots caused by birth controls develop in the leg. She was one of the few who’s blood clot formed in between my left clavicle and axila. She was considered a high risk patient because the blood clot could move to her brain, heart, or lungs in a moments notice, resulting in immediate death.

Nathalie continues, “all of this could have been avoided had my doctors or gynecologists accurately diagnosed me with endometriosis in my early teen years, or at the very least warned me that it is not advised for females to be on birth control longer than 5 years due to increased risk of blood clots and infertility.”

Now, thanks to this misdiagnosis, she needs to get a “rib resection” to alleviate the compression caused by the blood clot in her left clavicle. This is an invasive cardio vascular surgery that could have been prevented had she’d been educated about the risks of the prolonged use of hormonal birth control pills as well as the dangers of endometriosis.

Because her endometriosis was diagnosed 14 years late, she’s much more likely to be infertile compared to the average woman.

“I find it ironic living in a world where women are pressured to birth children, yet society doesn’t educate us enough about the female reproductive system because it’s taboo.” — Nathalie

Endometriosis 101

Endometriosis happens when the endometrium, the tissue that usually lines the inside of a woman’s uterus, grows outside it and attach to other parts of your body. This tissue acts like regular uterine tissue does during your period: It will break apart and bleed at the end of the cycle. But this blood has nowhere to go. Surrounding areas may become inflamed or swollen, potentially resulting in scar tissue and lesions.

This affects 11% of all women — 200 million women have endometriosis. Despite this, in the United States alone, where endo affects 7.6 million women, 13x more than the number of people cancer kills (<600,000), it receives 714x less research money than cancer (~5 billion) per year.

Why Does It Exist

  1. Doctors don’t know exactly what causes endometriosis. Some experts think menstrual blood that contains endometrial cells may pass back through your fallopian tubes and into your pelvic cavity, where the cells stick to your organs. This is called retrograde menstruation.
  2. Your genes could also play a role. If your mom or sister has endometriosis, you’re more likely to get it. Research shows that it tends to get worse from one generation to the next.
  3. Some women with endometriosis also have immune system disorders. But doctors aren’t sure whether there’s a link.

“don’t know”, “some think”, “aren’t sure” → the exact pathogenesis (process by which a disease/disorder develops) is still unknown🤯

However, we do that endometriosis is

  • a complex inflammatory disease
  • estrogen-dependent

People with endometriosis have more estrogen than those who don’t, specifically they have estradiol (E2) which is the type of estrogen that monitors menstruation.

Greater estradiol levels → greater growth of the endometrial/uterus tissue AKA the endometrium → the thicker the tissue (which also grows outside the uterus onto other organs) → the greater the bleeding.

There’s MORE Endo Does Than Make You Feel Like “someone’s whipping a knife around in your insides?”

The major symptom of endo is the pain of cramps during periods affects your daily routines. However, there is long list of others that follow.

Serious consequences involve

  1. women struggling with anxiety or depression due to dealing with the symptoms however being unaware of the diagnosis. Medical treatments and mental health care can help, however suppressing the consequences, does not solve the problem.
  2. raising the risk of ovarian cancer or another cancer called endometriosis-associated adenocarcinoma.
  3. about 40% of women who have trouble getting pregnant have endometriosis. It makes it harder to get pregnant if the tissue growing outside your uterus causes scarring, which can affect your fallopian tubes and keep an egg and sperm from meeting. It can also stop a fertilized egg from implanting in the lining of your uterus. surgery can remove the extra tissue, which may make it easier to get pregnant. an alternative option: assisted reproductive technology (such as in vitro fertilization) to help you conceive.

Endometriosis Diagnosis SUCKS

Gender Pain Gap

On average, a women has endometriosis for at least 8 years before being diagnosed. This is primarily due to the gender pain gap. Scientists investigating gender differences in pain have found that not only do women report more pain throughout the course of their lifetime, they also experience it in more bodily areas, more often and for longer duration when compared to men, which is likely why the pains are neglected.

Historically, women’s health research has suffered largely because men have been making decisions about which conditions to give limited research funding to. people don’t talk about things like period pain, which HERE is obviously a major symptom of the condition.”

Oh boy, you thought that was all? Nope….

Low recognition of endo at the general practitioner (GP) level

Up to 20% of women with endometriosis have concurrent chronic pain conditions, including irritable bowel syndrome, interstitial cystitis/painful bladder syndrome, fibromyalgia, and migraines.

Prior to attributing pelvic pain to endometriosis, bowel, bladder, psychiatric, and musculoskeletal etiologies should be ruled out.

Given that endometriosis may be a diagnosis of exclusion, the diagnosis of endometriosis in a woman with pelvic pain is often delayed and stretches over several years.

If these symptoms are dismissed as primary dysmenorrhea, which it may be for some people, then a doctor won’t investigate further and this contributes to the delay in diagnosis and timely management of symptomatic endometriosis normalization of pain.


Painful periods have been normalized for far too long and there aren’t enough tools to catch the disease early. The fact that doctors may take women’s pain less seriously than men’s, which can lead to a late diagnosis or no diagnosis at all. Women end up “getting used” to our pain and stop bringing it up with doctors and OBGYNs. Growing up, most women are told that our pain was normal and that we just had to “suck it up”, so people stopped talking about it transparently.

“embarrassing”, “stigmatized”, “tolerate it”

The prime concern is the uncertainty of normal versus abnormal symptoms and physician-centered causes such as normalization of patient symptoms


Endometriosis symptoms are nonspecific and overlap with other gynecologic and gastrointestinal diseases, leading to long diagnostic delays, or are misdiagnosed with diseases like dysmenorrhea and irritable bowel syndrome.

In a prospective study that the World Endometriosis Research Foundation (WERF) conducted, we found that 50% of people that were referred with bowel issues to a gastroenterologist actually had endometriosis and not bowel issues. Those with painful symptoms need to see a gynecologist and it’s not about seeing any gynecologist

Inefficient + Unreliable Diagnosis Options

  1. Pelvic exam

During a pelvic exam, your doctor manually feels (palpates) areas in your pelvis for abnormalities, such as cysts on your reproductive organs or scars behind your uterus.

In several studies, visual diagnosis of endometriosis has been demonstrated to be unreliable. Only 54–67% of suspected endometriotic lesions are confirmed histologically, and 18% of patients clinically suspected to have endometriosis have no evidence of endometriosis on pathology. Indeed, a 2004 metaanalysis which assumed a 20% prevalence of endometriosis found that “a positive finding on laparoscopy will be incorrect in half of the cases.

👎🏻 Often it’s not possible to feel small areas of endometriosis unless they’ve caused a cyst to form.

2. Ultrasound

This test uses high-frequency sound waves to create images of the inside of your body. To capture the images, a device called a transducer is either pressed against your abdomen or inserted into your vagina (transvaginal ultrasound). Both types of ultrasound may be done to get the best view of the reproductive organs.

👍 cheaper 👎🏻User-dependent + A standard ultrasound imaging test won’t definitively tell your doctor whether you have endometriosis, but it can identify cysts associated with endometriosis (endometriomas).

3. Magnetic resonance imaging (MRI)

An MRI is an exam that uses a magnetic field and radio waves to create detailed images of the organs and tissues within your body. detailed information about the location and size of endometrial implants. 👍 more accurate than ultrasound

👎🏻 inefficient , expensive ( $400 to $10500 ), not accessible

4. Laparoscopy ⚱️

The “gold standard” for endo🥇 Surgery for a procedure that allows the surgeon to view inside your abdomen (laparoscopy). While you’re under general anesthesia, your surgeon makes a tiny incision near your navel and inserts a slender viewing instrument (laparoscope), looking for signs of endometrial tissue outside the uterus.

A laparoscopy can provide information about the location, extent and size of the endometrial implants. Your surgeon may take a tissue sample (biopsy) for further testing. Often, with proper surgical planning, your surgeon can fully treat endometriosis during the laparoscopy so that you need only one surgery.

👍🏼only way to confirm a diagnosis of endometriosis. The most common surgery is called laparoscopy.

👎🏻 invasive, scars, people are scared

The Ideal Future

Women get diagnosed in a manner that’s easy, affordable, and without surgery. I am building this future. We’re developing a solution that will make endometriosis diagnosis 70080x faster & 320x cheaper.


EndoLoop is a moonshot startup my team and I are developing which is ending the loop of endometriosis by revolutionizing diagnosis.

At EndoLoop, our mission is to revolutionize the diagnosis of endometriosis. Our testing method is non-invasive, rapid, and affordable.

If a patient experiences the symptoms of endometriosis, they simply travel to their closest point of care — this could be any primary care doctor or pharmacy.

A doctor, nurse, or pharmacist would extract a few drops of blood with a finger prick test, and the patient will receive a positive or negative test result for endometriosis within one hour!

Here’s how this would work behind the scenes

MicroRNA Biomarkers

original visual made by my team

Scientists have recently begun to investigate the role of microRNAs (miRNA) as biomarkers for a host of diseases, especially cancers.

To understand the role of miRNAs, remember how genes translate to biological functions: when translating our genetic code (DNA) into a cell’s biological functions, the DNA is transcribed into messenger RNAs (mRNAs) which are converted to proteins by ribosomes.

MicroRNAs are short, single-stranded, RNA molecules that help cells degrade or block the translation of mRNAs, effectively stopping the production of certain proteins. This can block or alter cellular functions and lead to some of the symptoms of endometriosis.

Promising new research have indicated that levels of various miRNAs, when taken together, can serve as extremely accurate biomarkers for endometriosis.

How the test actually works

Finger prick for blood sample

Instead of requiring an extensive, expensive surgery (laparoscopy) to diagnose endometriosis, testing blood obtained via a fingerprick device provides an effortless and widely accessible method of retrieving blood for analysis. This does not require a doctor or specialist: any pharmacist or nurse is perfectly capable of retrieving the blood in this way.

Microfluidic chip

Left: Schematic of a microfluidic chip (μPAD) from blood sample to colorimetric output of miRNA level. Right: Visualization of blood separation process in microchannels of the μPAD.

A core element of EndoLoop’s technology consists of microfluidic chips: an emerging technology that can translate a tiny blood sample into detailed insights to make a diagnosis.

Commonly known as a “labs on a chip,” microfluidic chips are small devices with micro-channels that can manipulate liquids and test them for certain substances.

In this case, it can separate a liquid sample into its components and detect the presence of biomarkers.

EndoLoop specifically uses microfluidic paper-based analytical devices, or µPADs, because they are low cost and easily disposable after use. At high production quantities, we expect each paper microfluidic device to have a materials and manufacturing cost between $1 and $3.

The microfludic chips perform two essential functions in the test for endometriosis: separating the plasma from the blood sample, and detecting the presence of target miRNAs.

Without microfluidics, separating a blood sample into the red blood cells and the surrounding liquid, or plasma, requires spinning a large blood sample at high speeds with expensive equipment. Paper-based microfluidic devices can perform rapid separation of blood from plasma with a very small sample.

Similarly, microfluidics overcome the current challenges with detection of miRNA levels. Currently used mechanisms for testing for miRNAs are complex and expensive, requiring technologies like qPCR (a similar technology to what is used for COVID-19 testing) and microarrays (which require specialized equipment).

The microfludic chip, on the other hand, makes the detection of miRNA levels quite simple. Each indicator has an enzyme with an miRNA template that binds to the target miRNA if it is present in the plasma, catalyzing a chemical reaction that changes color.

Higher concentrations of each miRNA will result in a deeper color in its respective indicator, creating a colorimetric detector for the levels of each endometriosis-associated miRNA (marked 1–6 in the diagram).

AI-powered app

Once the microfluidic chip completes the analysis of the blood sample, the person administering the test would use EndoLoop’s app and take a picture of the microfluidic chip.

This app would be available on smartphones or computers, and would not depend on internet access.

The software would automatically translate the colorimetric information from the chip into a numerical value for the concentration of each miRNA (this would be resilient to different lighting conditions and cameras).

This information is then put into a random forest algorithm, which classifies the patient as either positive or negative for endometriosis✅

Gap between EndoLoop’s vision and today’s reality

miRNA Biomarker research

Current research on miRNA biomarkers for endometriosis place the potential accuracy at up to 94–100% when the concentrations of three-six miRNA are analyzed with machine learning algorithms. However, there is no consensus on which biomarker(s) to rely on for the endometriosis diagnosis, since most research to date has been relatively small-scale and not included the full range of potential endometriosis patients; for instance, the efficacy of these biomarkers has not been investigated for pre-symptomatic endometriosis patients. The success of EndoLoop relies on a large-scale trial to definitively determine the most reliable suite of miRNA biomarker for use in our testing, and ensuring that the accuracy for this is extremely high even at early stages of endometriosis.

Artificial intelligence analysis of microfluidic output

The use of image-processing to analyze the colorimetric output of microfluidic chips has been validated by recent research. However, further investigation is required to ensure that this is accurate enough for the machine learning algorithm to precisely predict whether a patient has endometriosis.

Endometriosis education

Our diagnosis system is only effective if people know to get tested for endometriosis and what symptoms to look out for. Once we finalize and validate the diagnostic technology, we plan to engage doctors around the world in a wide-scale endometriosis education campaign to ensure that testing women for endometriosis through our method becomes commonplace.

Market Opportunity

The fertility market is expected to reach $36B+ by 2026, and the endometriosis market is estimated to reach $2.4B+ by 2026.

Though the cost of the paper microfludic device itself is $1 to $3, and the disposable lancet costs a few cents, there are numerous other costs that will go into building a company like EndoLoop, including the development of the AI algorithm, clinical trials, distribution, and much more.

Additionally, the test provides an extraordinary value because the laparoscopy to receive an endometriosis diagnosis would cost between $5000 and $9000. $15–30 range is standard cost for simple in-hospital / doctor’s office tests (e.g. urine analysis, blood count. For these reasons, we choose to price EndoLoop’s test at $25 per test. We want it to affordable and easy to access.

We anticipate that an initial expansion to the United States could achieve $1.2M in annual revenue, which could increase to $14M soon after as the test becomes more prevalent and spreads to other countries.

Bringing EndoLoop To Market | R&D Perspective

  1. Large-scale data collection

The first step to making Endoloop a reality is gathering large amounts of mciroRNA data from patients with and without endometriosis.

We would run microRNA tests through standard lab procedure (qPCR rather than microfluidics) and obtain the levels from patients for ~15–20 candidate miRNAs that could potentially serve as the most accurate biomarkers.

With this data (need on the order of 5k-20k data points, with equal numbers of patients with and without endometriosis), we can determine which miRNA levels correlate most closely with endometriosis.

After deciding on 4–8 microRNAs that together can provide the best diagnosis, we input the data collected (80/20 split into train and validation) into the random forest classifier as training data, and ensure that the sensitivity and specificity each exceed 90% on both the training and validation data.

2. Colorimetric validation
The second step to making EndoLoop a reality is ensuring that the colorimetric detection of miRNAs on the microfluidic chip provide levels of microRNAs that are accurate enough for the ML algorithm to make the correct diagnosis.

This will involve testing the same blood samples with:

  1. qPCR (gold standard) for a baseline result
  2. Colorimetric + Spectroscopy (ensure precision of colorimetric reaction on microfluidic chip)
  3. Colorimetric + phone camera (with computer vision processing) to ensure that a smartphone camera can correctly obtain accurate miRNA levels, adjusting for different cameras + lighting conditions

Essentially, R&D work will be required to fine-tune the microfluidic reaction sensitivity and the image processing pipeline to ensure that we have accurate enough data to work with.

3. Clinical trials
After the full pipeline including microfluidic chip manufacturing, image processing, and AI algorithm have been developed, the EndoLoop technology needs to be tested on a large scale to ensure its efficacy.

An important question this trial could answer is whether this allows for a diagnosis at early stages of the disease, before a trial participant had even received a diagnosis via a standard method used today (laparoscopy, ultrasound, etc).

Now millions of women around the world won’t have to go through the struggles Nathalie did. Accessible and affordable autonomy over your female health. This’ll change lives👧🏽🩸💪🏽.

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