In recent years, collagen has become the “it” protein, showing up being added to coffee and smoothies, and found in cute canisters all over Instagram. But when you’re trying to conceive or you’re pregnant, it’s fair to ask: does collagen actually help, is it safe, and how does it fit into a fertility-forward nutrition plan?
Collagen is the most abundant structural protein in the body. Think skin, joints, ligaments, connective tissues, and even parts of the placenta. Most supplements use hydrolyzed collagen (collagen peptides), which are pre-broken down so they dissolve easily and are absorbed more readily. That said, collagen is not a complete protein, meaning it lacks an essential amino acid, in this case tryptophan, so the way you use it matters. It’s a great add-on, but not a one-stop replacement for other proteins.
RELATED: Protein for fertility & pregnancy: The complete guide for men and women
What is collagen protein?
It acts as a structural framework, giving strength and elasticity to your skin, joints, ligaments, tendons, blood vessels, gut lining, and even parts of the placenta. If protein is the body’s building material, collagen is the scaffolding that holds everything together.
Collagen peptides are rich in glycine, proline, and hydroxyproline, amino acids your body uses to build connective tissue, support joint health, maintain skin elasticity, and reinforce the gut lining. During pregnancy, glycine becomes particularly important because collagen demand increases as tissues stretch and expand.
However, collagen lacks certain essential amino acids, most notably tryptophan, and is low in others like methionine and leucine. That means it doesn’t provide the full amino acid spectrum needed for hormone production, fetal growth, or sperm development.
In practical terms, collagen shouldn’t “replace” protein sources like eggs, fish, dairy, poultry, or well-combined plant proteins. Instead, it works best as a supportive addition, helping nourish skin, joints, ligaments, and connective tissue, while you meet your core protein requirements through complete protein sources.
Think of collagen as the connective tissue specialist in your nutrition plan, not the whole construction crew.
Collagen and fertility health
For Women
Collagen can be part of a fertility-friendly diet by supporting connective tissues, pelvic stability, and skin and ligament comfort as training volume changes or pregnancy advances. While there aren’t RCTs showing collagen directly improves egg quality, collagen peptides may increase antioxidant capacity and support healthy skin matrix proteins, suggesting an indirect “terrain-building” role when paired with complete proteins and micronutrients.
If you’re optimizing overall protein intake for preconception or pregnancy, remember that total daily protein is what moves the needle on hormones, egg quality, and uterine lining, not collagen alone.
For Men
On the male side, fertility is tightly linked to oxidative stress and DNA integrity in sperm. Antioxidant-supportive patterns like eating adequate protein, colorful plants, omega-3s, and using targeted supplements, can help reduce damage from reactive oxygen species. Collagen isn’t a magic bullet here, but as part of a balanced protein strategy, it can support joint health and training consistency, which indirectly benefits metabolic and hormonal health.
Collagen During Pregnancy
During pregnancy, many people like collagen for skin elasticity, joint comfort, and connective-tissue support which are all very reasonable goals as your body changes. The cosmetic literature suggests collagen peptides can improve skin hydration and elasticity and reduce the appearance of fine lines over 8–12 weeks, though most studies are not in pregnant populations and many are industry-funded.
How this translates? Collagen is promising for skin, but not definitive, and not pregnancy-specific.
A note on safety as there aren’t large RCTs in pregnant individuals. Collagen peptides are widely considered generally safe foods, but because supplements vary in quality, the conservative approach is to:
- choose third-party tested brands, and
- use collagen as a complement to a diet rich in complete proteins (eggs, dairy if tolerated, fish, poultry, legumes + whole grains).
Collagen vs. other protein sources
Because collagen lacks tryptophan (and is low in other essential amino acids), it can’t replace complete proteins in a fertility or prenatal plan. Think of it like this: let eggs, dairy or soy/legume-grain combos be the foundation, and let collagen be the upgrade for connective tissue and skin. If you love collagen in your morning latte, great! Just make sure the rest of your day includes complete protein at each meal.
Best ways to add collagen for fertility & pregnancy
Most collagen peptide studies use 2.5–15 g/day, often split between morning coffee/tea and a smoothie or soup. That’s a sensible range for general connective-tissue and skin support. If you’re pregnant or TTC, keep total daily protein intake aligned with your needs (use collagen to help, not to carry the load), and pair it with vitamin C-rich foods (citrus, berries, peppers) to support collagen synthesis.
Putting it together with your total protein targets
From a fertility perspective, total daily protein drives outcomes more than any single powder. Newer data using the indicator amino acid oxidation (IAAO) method suggest pregnancy protein needs are higher than older RDAs, especially in late gestation (roughly ~1.2 g/kg early and ~1.5 g/kg late). Collagen can help you hit the number comfortably, but it shouldn’t displace complete proteins that supply essential amino acids for hormones, fetal growth, and maternal tissue.
WeNatal Prenatal Protein+ for Her
WeNatal Prenatal Protein+ for Him
FAQs about collagen to support fertility and pregnancy
Is collagen safe during pregnancy?
There’s no strong evidence of harm when using reputable, food-grade collagen peptides, but high-quality pregnancy-specific trials are lacking. Choose third-party tested brands and use collagen to supplement a balanced diet, not replace it.
Can collagen replace my prenatal protein powder?
No. Collagen is incomplete (missing tryptophan), so it’s best in addition to complete proteins like a protein powder that also contains whey protein or paired with a balanced meal that includes a source of complete protein.
Does collagen help with stretch marks?
Topical products for stretch-mark prevention show mixed to limited evidence; oral collagen improves skin hydration/elasticity in general populations, but pregnancy-specific data are limited. Consider it supportive, but not a guarantee.
What about male fertility, can collagen help?
Not directly, but as part of an overall plan that improves training consistency, joint comfort, supporting gut lining, and recovery, collagen can indirectly support the lifestyle pieces tied to sperm quality. Reducing oxidative stress and meeting overall protein needs are bigger levers.
A note from WeNatal on collagen for fertility and the best collagen for pregnancy
We see collagen as one piece of a much bigger picture. When used thoughtfully, collagen for fertility and pregnancy can be a supportive addition by helping nourish connective tissue, support skin and joint comfort, and contribute to overall resilience during a time when your body is constantly adapting and rebuilding. As we’ve explored, the best collagen for pregnancy isn’t about finding a magic powder, it’s about pairing collagen with complete proteins, essential micronutrients, and a whole-foods foundation that truly supports hormone health, egg and sperm quality, and healthy fetal development.
That’s why we created WeNatal Protein + for Her and Protein + for Him: to go beyond basic protein and offer targeted nutrient support designed specifically for the fertility journey. Our goal has always been to meet couples where they are, whether you’re trying to conceive, navigating pregnancy, or rebuilding strength postpartum. We provide tools that make nourishing your body feel simple, supportive, and sustainable. And we’re just getting started. As our community grows, so will the resources, education, and products designed to help you feel confident in every stage of your journey. Because when you combine smart protein choices, collagen used intentionally, and the right foundational nutrients, you’re not just supporting fertility, you’re building the strongest possible foundation for what comes next.
RELATED: The ultimate preconception guide: What to do when you’re ready to get pregnant
References
Ivaskiene T, Viskelis J, Streimikyte P, Savickaitė M, Mobasheri A, Kaspute G. Collagen supplementation and regenerative health: advances in biomarker detection and smart material integration. Front Nutr. 2025;12:1716166. Published 2025 Dec 11. doi:10.3389/fnut.2025.1716166
Rasmussen BF, Ennis MA, Dyer RA, Lim K, Elango R. Glycine, a Dispensable Amino Acid, Is Conditionally Indispensable in Late Stages of Human Pregnancy. J Nutr. 2021;151(2):361-369. doi:10.1093/jn/nxaa263
Shamsi MB, Imam SN, Dada R. Sperm DNA integrity assays: diagnostic and prognostic challenges and implications in management of infertility. J Assist Reprod Genet. 2011;28(11):1073-1085. doi:10.1007/s10815-011-9631-8
Wang Y, Fu X, Li H. Mechanisms of oxidative stress-induced sperm dysfunction. Front Endocrinol (Lausanne). 2025;16:1520835. Published 2025 Feb 5. doi:10.3389/fendo.2025.1520835
Wu M, Cronin K, Crane JS. Biochemistry, Collagen Synthesis. [Updated 2023 Sep 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-.
