When reproductive biologist and Nobel laureate Robert Edwards, along with embryologist Jean Purdy, were preparing the first successful IVF, a clear idea was at the center: biology can be precisely influenced. Today, nutrition research shows how significantly our everyday decisions can change the likelihood of spontaneous conception. This is not wellness romanticism, but measurable biology—with levers that can be integrated into any high-performance routine.

Fertility is the ability to conceive within a certain period; professionals refer to fecundabilityprobability of conception in a cycle and subfertilitydelayed conception, usually >12 months. Hormones regulate this process—particularly FSHfollicle-stimulating hormone for egg maturation, progesteronehormone of the luteal phase, stabilizes the uterine lining and the insulin axis, which regulates sugar metabolism. Two groups of nutrients are critical: fats and carbohydrates. It is not merely the quantity that matters, but the quality—namely, the ratio of omega-3 to omega-6, avoidance of trans fats, and the glycemic load of meals. Equally central are antioxidants that buffer oxidative stressexcess reactive oxygen species that damage cells, and vitamin D, which binds to receptors in the ovaries and endometrium.

Higher omega-3 intake is associated in studies with better pregnancy and fertilization rates—both in natural conception and in the context of IVF ^[1]. Conversely, an unfavorable ratio of omega-6 to omega-3 correlates with lower fecundability, while a lower ratio is advantageous ^[2]. Trans fats degrade egg and sperm quality and are associated with ovulatory infertility; even a slight increase in the energy mix significantly raises the risk ^{[3] [4]}. Carbohydrates with a high glycemic load increase insulin spikes, disrupt hormonal balance, and elevate the risk of ovulatory disorders ^[5]. Inadequate antioxidants promote oxidative stress, which can damage ovulation, egg quality, and tubal function—a targeted intake of antioxidants shows potential in studies to improve egg reserve and outcome parameters, although further high-quality studies are needed ^[6]. Finally, vitamin D acts as a hormone modulator in the reproductive tract; deficiency states are increasingly associated with fertility problems, and consolidating studies are ongoing ^[7].

A recent meta-analysis aggregated data from studies on women wishing to conceive and on IVF/ICSI. The result: omega-3 intake was significantly associated with higher pregnancy and fertilization rates, despite the heterogeneity of the data. Clinical relevance: omega-3 seems to increase the likelihood of natural conception and improve laboratory endpoints like fertilization rates—a strong indication of a systemic effect on egg and endometrial quality ^[1]. In a prospective cohort study, the periconceptional nutrition of both partners was examined. In women, higher omega-3 intake—especially DHA and ALA—was linked to increased fecundability and lower subfertility; a lower omega-6:omega-3 ratio was beneficial. Interestingly, in men, higher nut and seed intake correlated with better fecundability, independent of omega-3, suggesting additional nutrient and antioxidant effects ^[2]. Additionally, a large prospective analysis showed that the percentage of energy from trans fats increases the risk of ovulatory infertility, particularly when trans fats replace healthy fats. Practical takeaway: It is not fat in general, but types of fats that govern reproductive signals—reduce trans fats, increase unsaturated fats ^{[3] [8]}.

- Increase the intake of low-fat fish: 2–3 servings/week of salmon, small mackerel, herring, or trout provide EPA/DHA for a favorable omega-6:omega-3 ratio; alternatively, supplement with algal oil (DHA/EPA 250–500 mg/day) if you do not eat fish ^{[1] [2]}.
- Consistently reduce trans fats: avoid hydrogenated fats in baked goods, fast food, and cheap snacks; cook with olive oil or canola oil, and use avocado/nuts as fat sources. Aim: trans fats <1% of total energy intake ^{[4] [8] [3]}.
- Increase plant-based proteins: incorporate legumes (lentils, chickpeas, beans) and soy into main meals; moderately combine nuts/seeds (a handful/day) for protein, micronutrients, and antioxidants. Ensure sufficient total intake of plant protein to support ovulation ^{[9] [2]}.
- Stabilize blood sugar: replace refined sugars and white flours with whole grains, beans, and vegetables; include protein and fat in every meal to lower the glycemic load and support hormonal balance ^[5].
- Optimize vitamin D: check 25-OH-D levels in the blood; aim for sufficient levels after consulting a doctor. Sun exposure (briefly, without sunburn) and, if needed, supplement with 1000–2000 IU/day, adjusting individually ^[7].
- Boost antioxidants: “Eat the rainbow” daily—berries, green leafy vegetables, colorful vegetables, herbs; optionally use combined antioxidants (e.g., vitamins C/E, selenium, CoQ10) in consultation, as there is evidence, but further RCTs are pending ^[6].

Fertility measurably reacts to dietary quality—a powerful lever for anyone who wants to combine performance in life and the desire for children. Next step: eliminate trans fats this week, plan two fish meals (or start algal oil), firmly incorporate legumes, and check vitamin D status.