Marine Collagen and Pregnancy: What the Uncertainty Is

There is no clinical evidence confirming that marine collagen is safe to take during pregnancy, and there is no clinical evidence confirming that it is harmful. Both of those facts matter. Most of the content circulating on this topic falls into one of two traps: unqualified reassurance or unqualified alarm. Neither is honest, and neither helps you make a decision.

If you are pregnant or trying to conceive and wondering whether to take marine collagen, the right person to ask is your GP or midwife. That is not a deflection. It is the only answer that accounts for your individual circumstances, your health history and your stage of pregnancy.

Why the evidence gap exists

Pregnant women are routinely excluded from clinical trials for ethical reasons. That means the research base for almost any supplement taken during pregnancy is thin, and marine collagen is no exception. The studies that do exist on collagen peptides in general are conducted in non-pregnant adults, predominantly women over 40 looking at skin or joint outcomes. None of those findings transfer directly to pregnancy, where physiology, nutritional demands and risk profiles are substantially different.

The absence of evidence is not the same as evidence of absence. It simply means nobody has run the trial, and until someone does, the honest position is uncertainty.

What marine collagen actually is

Marine collagen is a hydrolysed protein derived from fish. Hydrolysis breaks the collagen down into shorter peptide chains that dissolve readily. The protein profile is dominated by glycine, proline and hydroxyproline, amino acids that are also present in meat and fish consumed as food.

At a typical serving, you are consuming a relatively small quantity of fish-derived protein. That is not a reason to assume safety during pregnancy, but it does help frame what the substance is: a food-derived protein, not a synthetic compound or pharmaceutical. Whether that matters to your GP or midwife's assessment is for them to judge.

The fish allergen is relevant here

Marine collagen contains fish. That is not a minor footnote. Anyone with a fish or shellfish allergy or intolerance should not take it, pregnant or otherwise. If you have not previously had a reaction to fish, that is useful context, but pregnancy can affect immune sensitivity in ways that are not fully predictable.

Our Marine Collagen Powder is made from 100% hydrolysed collagen derived from wild-caught North Atlantic fish. That allergen status should be part of any conversation you have with a healthcare professional about whether the product is appropriate for you during pregnancy.

Heavy metals and sourcing

A concern sometimes raised about marine products is contamination with heavy metals such as mercury or lead. This is a legitimate question for any fish-derived product. When evaluating a marine collagen product, it is reasonable to ask whether batch testing for heavy metals is conducted and whether certificates of analysis are available from the supplier. If you cannot find that information for a product you are considering, ask the brand directly before purchasing.

What about collagen from other sources?

If the fish-derived nature of marine collagen is a concern, it is worth knowing that bovine collagen comes from cattle hides rather than fish. The allergen profile is different. However, the same fundamental point applies: there is no clinical evidence base confirming the safety of any collagen supplement specifically during pregnancy. Switching source does not resolve the evidence gap.

There is a broader discussion of the differences between marine and bovine products in our guide on which collagen to choose, though that article is not written with pregnancy in mind and should not be treated as advice on this question.

What to do if you were already taking it

If you started taking marine collagen before you knew you were pregnant and are now concerned, speak to your GP or midwife at your next appointment. There is no established evidence of harm from short-term use, but that is different from a reassurance of safety. Your healthcare team can assess your specific situation.

Claims you may have seen elsewhere

You may have come across articles stating that marine collagen supports skin elasticity during pregnancy, or helps with joint discomfort, or benefits the developing baby. None of those claims are supported by clinical evidence in pregnant populations. Under UK food supplement law, no authorised health claim exists for collagen of any kind. Articles making those claims are not drawing on a research base that exists.

Equally, articles stating that marine collagen is definitively unsafe during pregnancy are also not drawing on established evidence. The honest position is that we do not know, and the person best placed to weigh that uncertainty alongside your individual health is your GP or midwife.

If you want to understand more about what marine collagen actually contains and how to read a product label, our guide on what to look for in a marine collagen powder covers sourcing, protein content and what hydrolysed means in practice.