Collagen During Pregnancy and Breastfeeding: What Is Known, What Is Not

Collagen has not been studied in pregnant or breastfeeding women, so nobody can honestly tell you it is proven safe or proven beneficial in pregnancy. What can be said is this: hydrolysed collagen is a food-derived protein, chemically the same as the collagen you eat in meat, fish skin, bone broth and gelatin, and there is no known mechanism or reported harm from consuming it while pregnant. Protein needs rise in pregnancy and breastfeeding, and collagen is an easy, well-tolerated way to add protein. That is the whole evidence base. The right next step is to ask your midwife or GP, and this guide is meant to make that conversation easier, not to replace it.

Below: what collagen is and is not, why the usual supplement warnings do not apply in the same way, what actually to check on a label, the questions to ask your midwife, and the things collagen cannot do in pregnancy despite what some brands claim.

What collagen is, and why that matters here

Hydrolysed collagen is collagen from cattle hide or fish skin, broken down by enzymes into short peptides. Once digested it becomes the same amino acids (glycine, proline, hydroxyproline) you get from eating the skin on a roast chicken or a bowl of broth. It contains no hormones, no herbs, no caffeine and, in a clean product, no added vitamins. The reason the NHS advises caution with "supplements" in pregnancy is mainly about high-dose vitamin A, herbal ingredients and unregulated products, none of which apply to a plain collagen powder or shot. That does not make it studied; it makes it low-risk by category.

Why the trials do not exist

Pregnant women are routinely excluded from supplement trials for ethical reasons, so the absence of evidence is normal, not suspicious. It is the same situation as most protein powders, most sports drinks and many foods. What exists are the trials in non-pregnant adults showing hydrolysed collagen at 2.5g to 20g a day has an excellent safety record over 8 weeks to 12 months, with side effects limited to mild digestive fullness at high doses.

Protein needs in pregnancy and breastfeeding

UK guidance adds around 6g of protein a day in pregnancy and 11g to 15g a day when breastfeeding, on top of the usual 0.75g per kilo, and many women find nausea or appetite changes make hitting that hard. Collagen is one option among many: 20g of easily tolerated protein for 85 calories with no dairy, no gluten and no strong taste. It is not a complete protein, so it should sit alongside meat, fish, eggs, dairy or soy rather than replace them.

What to check on the label

• No added vitamin A (retinol). High-dose vitamin A is the supplement ingredient the NHS specifically warns against in pregnancy. Plain collagen does not contain it; some "beauty blends" do.
• No herbal extracts (ashwagandha, green tea extract, botanicals), which often lack pregnancy safety data.
• No caffeine or stimulants, sometimes added to "energy" collagen drinks.
• No high-dose vitamins or minerals beyond what your pregnancy multivitamin already supplies.
• Batch testing. Informed Sport certification means every batch is tested for contaminants and banned substances by an independent laboratory. That is not a pregnancy approval, but it is the best third-party check on what is in the sachet.
• A short ingredient list. KUDU liquid collagen is hydrolysed bovine collagen, water, natural flavourings and acidity regulators, with 0g sugar. KUDU Collagen + Creatine also contains creatine and vitamin C; creatine has less pregnancy data and is a separate discussion with your midwife.

What to ask your midwife or GP

1. "Is there any reason I should not add a food-derived protein supplement to my diet?" (Some conditions, such as certain kidney problems, need protein managed.)
2. "Are there any ingredients in this product you would want me to avoid?" Bring the label.
3. "How much protein should I be aiming for?"

What collagen will not do in pregnancy

You will see claims that collagen prevents stretch marks, supports the pelvic floor, or protects joints as ligaments loosen. These are mechanistically plausible and completely untested. Stretch marks are driven mostly by genetics and the rate of skin stretch; no supplement has been shown to prevent them. Pelvic floor and joint laxity in pregnancy are hormonal. If you take collagen in pregnancy, take it as a source of protein, not as a treatment for any of these.

Breastfeeding

The same logic applies: no trials, no known risks, and a food protein that is broken down to amino acids before it reaches milk. Protein and fluid needs are higher while breastfeeding, and a ready-to-drink protein is convenient in the early weeks. Ask the same questions of your health visitor or GP.

If you and your midwife decide a plain collagen protein fits your pregnancy diet, KUDU liquid collagen is 20g of hydrolysed bovine collagen, 85 calories, 0g sugar, no added vitamins or herbs, Informed Sport batch tested. We would rather you asked first than took our word for it.

Collagen in pregnancy: FAQs

Is collagen safe during pregnancy?

It has not been tested in pregnancy trials. It is a food-derived protein with no known risks, equivalent to eating gelatin or slow-cooked meat, but you should ask your midwife or GP before adding any supplement.

Can I take collagen while breastfeeding?

There are no trials and no known risks. Collagen is digested into amino acids like any dietary protein. Ask your health visitor or GP.

Does collagen prevent stretch marks?

No evidence supports this. Stretch marks are mainly genetic and related to how fast skin stretches.

What should I avoid in a collagen supplement during pregnancy?

Added vitamin A, herbal extracts, caffeine and high-dose vitamins. Choose a plain, batch-tested product with a short ingredient list.

How much protein do I need in pregnancy?

UK guidance adds about 6g a day in pregnancy and 11g to 15g when breastfeeding, on top of the usual 0.75g per kilo of body weight. Collagen can contribute but should not replace complete proteins.

Related reading

• Collagen side effects
• Are your collagen supplements safe?
• Does collagen actually work?
• Hydrolysed collagen vs collagen peptides

Sources

• NHS. Vitamins, supplements and nutrition in pregnancy.
• Scientific Advisory Committee on Nutrition. Dietary reference values for protein, including pregnancy and lactation increments.
• Paul C, Leser S, Oesser S. Significant amounts of functional collagen peptides can be incorporated in the diet while maintaining indispensable amino acid balance. Nutrients 2019.
• European Food Safety Authority. Scientific opinion on the safety of collagen hydrolysate as a food ingredient.