The single most important supplement to start before trying to conceive is folic acid, at 400 micrograms daily. The CDC recommends this for all women who could become pregnant, because it prevents neural tube defects that develop in the earliest weeks of pregnancy, often before you know you’re pregnant. But folic acid is just the starting point. A good prenatal vitamin, targeted nutrients, and the right dietary pattern can meaningfully improve your odds of conception and a healthy pregnancy.
Start a Prenatal Vitamin 1 to 3 Months Early
Fertility specialists recommend beginning a preconception supplement one to three months before you start trying. This lead time matters because egg development takes roughly 90 days, so the nutrients you take now influence the quality of eggs maturing over the next few cycles. Starting early also ensures your body has adequate stores of key nutrients before the demands of early pregnancy kick in.
A solid prenatal vitamin should contain folic acid and iron at minimum. Beyond those two, look for calcium, vitamin D, iodine, zinc, vitamin C, vitamin E, and B vitamins. Not all prenatals are created equal, so check the label rather than assuming everything is covered. If your prenatal doesn’t include a particular nutrient listed here, a standalone supplement can fill the gap.
Iron and Ovulatory Fertility
Iron deserves special attention. Women who took iron supplements had a 40% lower risk of ovulatory infertility compared to women who didn’t, after adjusting for other factors. The protective effect came specifically from nonheme iron, the type found in supplements and plant foods like spinach, lentils, and fortified cereals. Iron from red meat (heme iron) showed no association with ovulatory fertility in the same research. If your prenatal contains iron, you’re likely covered, but it’s worth confirming the amount with your provider, especially if you have heavy periods or a history of low iron.
Omega-3 Fatty Acids Lower Pregnancy Loss Risk
The omega-3 fats DHA and EPA, found in fatty fish like salmon and sardines, play a striking role in early pregnancy survival. In a large prospective study of couples undergoing fertility treatment, women with the highest omega-3 intake had a 54% probability of live birth compared to 36% for women with the lowest intake. Even more notable: the risk of pregnancy loss among women in the top quartile of omega-3 consumption dropped to just 1%, compared to 36% in the bottom quartile.
These findings came from women in fertility treatment, so the exact numbers may not translate directly to natural conception. But the pattern is consistent: omega-3s appear to protect early pregnancies from loss. If you don’t eat fish two to three times per week, a fish oil supplement providing both DHA and EPA is a reasonable addition to your routine.
CoQ10 for Egg Quality
CoQ10 is an antioxidant your body produces naturally, but levels decline with age. It plays a direct role in cellular energy production, which is critical for egg development. Eggs are among the most energy-demanding cells in the body, and as they mature, they need enormous amounts of cellular fuel. CoQ10 supports that process while also protecting eggs from the kind of oxidative damage that accumulates over time.
Clinical studies have used doses ranging from 200 to 600 mg daily, typically for two to three months before conception attempts. CoQ10 is particularly worth considering if you’re over 35, since age-related fertility decline is partly driven by reduced mitochondrial function in eggs. It’s generally well tolerated, though you should mention it to your provider if you take blood thinners.
Eating for Fertility
Supplements work best on top of a strong dietary foundation, and the Mediterranean diet has the most evidence behind it for fertility. This eating pattern emphasizes vegetables, fruits, whole grains, legumes, nuts, olive oil, and fish while limiting processed foods and red meat.
In studies of women undergoing fertility treatment, those with the highest adherence to a Mediterranean diet had clinical pregnancy rates of 50%, compared to 29% for women with the lowest adherence. Live birth rates showed an even wider gap: 49% versus 27%. The effect held across multiple studies, with odds ratios for clinical pregnancy ranging from 1.4 to 2.7 depending on the study. Women who ate this way also produced more viable embryos and had a lower risk of unexpectedly poor ovarian response to treatment. You don’t need to overhaul your kitchen overnight, but shifting toward more fish, olive oil, vegetables, and whole grains is one of the most impactful things you can do.
What Your Partner Should Take
Fertility is a two-person project, and sperm quality responds well to targeted supplementation. Zinc is the most studied nutrient for male fertility. Men who supplemented with zinc for three months showed increases in sperm volume, forward motility, and total sperm count across multiple trials.
Selenium, often combined with vitamin E or other antioxidants, improved sperm motility and morphology in over half of men in one study of nearly 700 participants. Another trial of 468 men with poor sperm parameters found that selenium significantly improved all semen measurements over 30 weeks.
L-carnitine is another well-supported option. Every study examining its effect on sperm showed a positive relationship with sperm count, motility, and shape. In clinical trials, men typically took it for three to six months. A combination approach, using a men’s fertility supplement that includes zinc, selenium, L-carnitine, and CoQ10, covers the most evidence-backed bases. Sperm take about 74 days to fully develop, so your partner should start supplementing at least two to three months before you begin trying.
Inositol for PCOS
If you have polycystic ovary syndrome, inositol supplements can help restore regular ovulation. The most effective formulation combines two types: myo-inositol and D-chiro-inositol in a 40:1 ratio. This mirrors the natural ratio found in the blood and has been shown in multiple clinical studies to be the best combination for normalizing hormones and triggering ovulation in women with PCOS. The typical dose used in research is 2 grams of combined inositols taken twice daily for at least three months. Inositol is not a replacement for other PCOS treatments your provider may recommend, but it’s a well-studied, low-risk addition.
Tracking Your Fertile Window
Taking the right supplements prepares your body, but timing intercourse correctly is just as important. You’re most fertile in the two to three days before ovulation. Ovulation predictor kits detect the surge in luteinizing hormone that happens 24 to 36 hours before an egg is released, giving you a short but actionable heads-up. Basal body temperature tracking, where you take your temperature first thing every morning, confirms ovulation after the fact but can’t predict it in advance. For most people, ovulation predictor kits are more practical, though they’re not perfect. False positives and false negatives happen, especially in women with conditions like PCOS that cause irregular hormone patterns.
Using both methods together gives you the fullest picture: predictor kits tell you when to try, and temperature tracking confirms that ovulation actually occurred.
Herbal Supplements to Be Cautious About
Not all supplements marketed for fertility are safe. Some herbal products can alter hormone levels in ways that interfere with ovulation or implantation. Others have been shown to cause uterine contractions that could lead to pregnancy loss. Herbal supplements are not regulated the same way as medications, so the actual contents and potency can vary between brands and even between batches. If you’re taking any herbal products, whether for fertility or unrelated reasons, bring the full list to your provider. Some herbal products can also affect male fertility, so this applies to your partner as well.