Stem cells come from several different sources: embryos, adult tissue such as bone marrow and fat, umbilical cord and placental tissue left over after birth, and lab-reprogrammed adult cells called iPSCs.

Each source has its own properties, collection method, and level of regulatory oversight, which is why knowing where a clinic’s cells actually come from matters before you consider treatment.

If you’ve ever wondered where do stem cells come from, you’re asking one of the most important questions in modern medicine.

Stem cells show up in headlines about cancer treatment, joint repair, and anti-aging therapy, but the cells themselves aren’t all the same.

Some come from donated embryos.

Others come from a patient’s own bone marrow or fat tissue.

A growing number come from umbilical cords and placentas that would otherwise be thrown away after a healthy birth.

Knowing what stem cells actually are is a good starting point, but the source matters just as much as the cell type.

Where a stem cell comes from affects how it’s collected, how it’s processed, and how it’s regulated before it ever reaches a patient.

This guide walks through every major source, in plain language, so you know exactly what you’re looking at the next time you read about a stem cell treatment.

What Are Stem Cells, Exactly?

Stem cells are the body’s raw material.

They’re unspecialized cells that can both copy themselves and turn into more specialized cells, like muscle, bone, or blood cells.

Every other cell in your body eventually traces back to a stem cell at some point in its development.

Scientists sort stem cells by how versatile they are.

Totipotent cells can become any cell type, including a whole organism.

Pluripotent cells can become almost any cell type in the body.

Multipotent cells are more limited, able to become only a handful of related cell types, like the different cells found in blood.

That range of potential is exactly why where a stem cell comes from matters so much.

A cell’s source largely determines which of these categories it falls into, and that shapes what it can realistically be used for.

Where Do Stem Cells Come From? The Main Sources

Stem cells are collected from a handful of distinct sources, each with its own advantages, limitations, and ethical considerations.

Here’s how the main categories break down.

Embryonic Stem Cells

Embryonic stem cells come from embryos at the blastocyst stage, just three to five days after fertilization.

Researchers extract them from the embryo’s inner cell mass, the cluster of cells that would otherwise go on to form an entire body.

These embryos typically come from IVF cycles that produced more embryos than a family needed, donated for research with informed consent rather than created for that purpose.

Embryonic stem cells are pluripotent, meaning they can turn into nearly any cell type in the body, which makes them scientifically valuable and also the most ethically debated source on this list.

Adult (Somatic) Stem Cells

Adult stem cells, also called somatic stem cells, live inside tissues throughout your body for your entire life.

Bone marrow and fat (adipose) tissue are the two most common sources, though smaller pools also exist in skin, muscle, and other organs.

Hematopoietic stem cells in bone marrow generate every type of blood cell, which is why bone marrow transplants have been used to treat blood cancers for decades.

Adipose tissue, meanwhile, is especially rich in mesenchymal stem cells, which can be collected through a procedure similar to liposuction.

Adult stem cells are multipotent rather than pluripotent, so they’re more limited in what they can become, but collecting them doesn’t raise the ethical questions tied to embryonic sources.

Perinatal Stem Cells: Umbilical Cord and Placenta

Perinatal stem cells come from tissue collected right after a healthy birth: umbilical cord blood, the cord tissue itself, and the placenta.

All of this material is normally discarded as medical waste, so collecting it doesn’t put the baby or birthing parent at any additional risk.

Umbilical cord blood has been used as a source of blood-forming stem cells since 1988, and it’s considered more readily available than bone marrow donations. 

Placental tissue is another rich, non-controversial source, carrying its own population of mesenchymal stem cells that researchers have studied for wound healing and tissue repair.

Induced Pluripotent Stem Cells (iPSCs)

Induced pluripotent stem cells don’t come from a donor tissue source at all.

Instead, scientists take ordinary adult cells, often from skin or blood, and reprogram them in a lab using specific genetic factors that reset the cell back to a pluripotent, embryonic-like state.

This approach, first developed in the mid-2000s, lets researchers generate pluripotent cells without using embryos at all.

iPSCs are now a standard tool for drug testing and disease modeling, though their use in direct patient treatment is still mostly confined to clinical trials.

What Is Wharton’s Jelly and Why Does It Matter?

Wharton’s jelly is the thick, gel-like connective tissue that surrounds the blood vessels inside the umbilical cord.

It’s packed with mesenchymal stem cells, and researchers consider it one of the most reliable, non-controversial sources of these cells available today.

Wharton’s jelly isolates mesenchymal stem cells successfully almost every time it’s collected, compared to roughly 60% for umbilical cord blood alone.

Cells from this part of the cord also show strong plasticity, meaning they can differentiate into bone, cartilage, fat, and other tissue types.

Because the umbilical cord is routinely discarded after birth, Wharton’s jelly collection doesn’t involve the tradeoffs tied to embryonic sources.

What Are Muse Cells and Where Do They Come From?

Muse cells, short for multilineage-differentiating stress-enduring cells, are a rare subset of adult mesenchymal stem cells discovered in 2010 by Dr. Mari Dezawa’s research group at Tohoku University in Japan.

They were found almost by accident, when researchers noticed a small group of cells that survived lab conditions that destroyed every other cell in the sample.

Small numbers of Muse cells naturally circulate in bone marrow, adipose tissue, and peripheral blood throughout a person’s life, which means they can be isolated from a patient’s own tissue or from donated sources like umbilical cord tissue.

What sets them apart is a built-in ability to find damaged tissue and home in on it through a specific receptor pathway, then spontaneously adapt to match the surrounding cell type once they arrive.

Unlike embryonic stem cells or iPSCs, Muse cells haven’t been linked to tumor formation in the research published so far, which is part of why interest in Muse cell therapy has grown in recent years.

How Are Stem Cells Collected and Processed Before Use?

Collection is only the first step.

Once stem cells are extracted from any source, they typically go through isolation, lab testing, and often culture-expansion before they’re ever used in a treatment.

Culture-expansion means growing a small starting sample of cells in a lab until there are enough to work with clinically, since a single donation rarely contains a usable dose on its own.

Depending on the treatment plan, culture-expanded cells may be used shortly after processing or stored for later use.

Storage comes with its own tradeoffs: fresh and frozen cells can behave differently once they’re introduced into the body, so reputable labs test both viability and potency before release, not just at the time of collection.

Are Stem Cells Regulated?

Yes, legitimate stem cell sourcing and use is regulated, though exactly how varies by country and by the type of cell involved.

Embryonic research is subject to strict ethical review wherever it’s permitted, while adult and perinatal cell products used in therapy generally fall under a national health authority, such as the FDA in the United States or COFEPRIS in Mexico, alongside professional standards from groups like the International Society for Stem Cell Research.

This oversight exists for a reason.

In 2026, the FDA issued a string of warning letters to clinics selling unapproved stem cell and exosome products, some tied to serious complications like infection and abnormal tissue growth.

That’s why the risks tied to any stem cell treatment usually trace back to how the cells were sourced and verified, not just the cell type itself.

A certificate of analysis from an independent lab is one of the clearest signs that a provider is actually testing what it claims to be using.

How Cellular Hope Institute Sources and Verifies Its Stem Cells

At Cellular Hope Institute, sourcing isn’t outsourced to a third party we can’t verify ourselves.

Our mesenchymal stem cells are expanded in-house through our sister lab, Cellgenic, using xeno-free, human plasma-based culture methods instead of the fetal bovine serum older protocols relied on.

Every batch goes through cell count verification, viability testing, sterility and endotoxin screening, and surface marker characterization before it’s released for use.

We also hold three separate COFEPRIS licenses, Mexico’s federal health regulator, covering tissue banking, tissue collection, and clinical application, which keeps our stem cell treatments and broader regenerative cell therapies accountable to the same kind of oversight described earlier in this guide.

Patients travel to our clinic in Cancun, Mexico from across the United States and Canada specifically because they want to see where their cells come from, not just take a provider’s word for it.

If certified sourcing standards matter to you as much as they should, our team is glad to walk you through exactly how our cells are produced and tested before you ever book a treatment.

Stem cells aren’t one single thing, and where they come from shapes almost everything else about them: how they’re collected, what they can become, and how closely their production needs to be regulated.

Embryonic, adult, perinatal, and lab-reprogrammed sources each bring their own strengths and limitations to the table.

If you’re considering a stem cell or Muse cell treatment, the source and verification process matter just as much as the condition you’re treating.

Cellular Hope Institute sources its cells in-house, tests every batch, and operates under Mexico’s COFEPRIS licensing framework, so you’re never left guessing where your treatment actually comes from.

FAQs

Where do stem cells come from?

Stem cells come from four main sources: donated embryos at the blastocyst stage, adult tissue like bone marrow and fat, perinatal tissue such as umbilical cord blood and placenta collected after birth, and lab-reprogrammed adult cells called induced pluripotent stem cells (iPSCs).

What is the most common source of stem cells used in therapy?

Bone marrow and adipose (fat) tissue are the most commonly used sources in current stem cell therapy, mainly because they can be collected directly from a patient and don’t involve the ethical considerations tied to embryonic sources. Umbilical cord and Wharton’s jelly derived cells have also become increasingly common.

Are stem cells taken from embryos?

Some are. Embryonic stem cells come from embryos at the blastocyst stage, usually donated from IVF cycles with informed consent. However, most stem cells used in current therapies come from adult tissue, umbilical cord tissue, or placentas instead, none of which involve an embryo.

What are Muse cells and how are they different from other stem cells?

Muse cells are a rare type of adult stem cell discovered in 2010 that can survive harsh stress conditions and naturally home in on damaged tissue. Unlike embryonic stem cells, they haven’t been linked to tumor formation in published research, and they don’t require lab reprogramming the way induced pluripotent stem cells do.

How do clinics verify that stem cells are safe and high quality?

Reputable clinics test every batch of cells for viability, sterility, and the presence of harmful endotoxins, and they confirm the cells carry the right surface markers for their intended use. A certificate of analysis from an independent lab, along with licensing from a national health regulator, are two of the clearest signs a provider is actually verifying what it’s using.

Is it safe to get stem cell therapy sourced from another country?

It depends on the clinic’s sourcing, testing, and regulatory oversight, not the country itself. Clinics operating under recognized licensing, such as COFEPRIS in Mexico or similar health authorities elsewhere, that openly share their quality control process offer much more accountability than providers who can’t explain where their cells come from.