Nutrition during pregnancy is a topic that attracts considerable attention—and a fair amount of conflicting advice. For women who are pregnant after 35, or who are trying to conceive, questions about which nutrients matter most, how much is needed, and how to get them from food versus supplements are particularly common. While the fundamentals of prenatal nutrition apply across ages, there are some nuances worth understanding for this stage of life.
It’s important to approach this topic with appropriate context: dietary needs during pregnancy are highly individual, and no article should substitute for personalized guidance from an OB/GYN, midwife, or registered dietitian. What follows is an evidence-informed overview of nutrients that current research identifies as particularly important during pregnancy and the preconception period—along with the food sources associated with them.
What Research Shows About Prenatal Nutrition
According to the Centers for Disease Control and Prevention (CDC), adequate nutrition before and during pregnancy is associated with better outcomes for both mother and baby. Key nutrients support fetal neural development, healthy placental function, maternal immune health, and the prevention of certain birth differences.
The nutritional demands of pregnancy increase significantly in many categories. While the adage of “eating for two” is nutritionally misleading—caloric needs increase by far less than doubling—the needs for specific micronutrients do rise substantially. This is why a high-quality prenatal vitamin, taken before conception and throughout pregnancy, is universally recommended.
Folate and Folic Acid
Folate—and its synthetic form, folic acid—is perhaps the most well-studied prenatal nutrient. Adequate folate intake in the weeks before conception and during the first trimester is associated with reduced risk of neural tube defects, including spina bifida and anencephaly. The recommended intake for pregnant women is 600 micrograms of dietary folate equivalents (DFE) per day; for those trying to conceive, supplementation with 400–800 micrograms of folic acid daily is typically recommended beginning before conception.
Folate-rich foods include dark leafy greens (spinach, kale, romaine), legumes, fortified grains, and citrus fruits. However, the amount needed during the critical neural tube development period (which occurs in the first 28 days after conception—often before pregnancy is confirmed) makes pre-conception supplementation particularly important.
L-Methylfolate: A Note on MTHFR Variants
Some women carry genetic variants in the MTHFR gene that affect how efficiently they convert folic acid to its active form. For those with relevant MTHFR variants, L-methylfolate (the active form) is sometimes recommended instead of or in addition to folic acid. Whether this is relevant to your situation is worth discussing with your healthcare provider if you’re aware of an MTHFR variant.
Iron
Iron needs increase substantially during pregnancy as blood volume expands and the fetus draws on maternal iron stores. The recommended daily intake of iron during pregnancy is 27 mg, compared to 18 mg for non-pregnant women of reproductive age. Iron deficiency anemia is common during pregnancy and associated with fatigue, reduced immunity, and potential impacts on fetal development.
Iron-rich foods include lean red meat, poultry, fish, legumes, tofu, and fortified cereals. Pairing plant-based iron sources with vitamin C-rich foods can enhance absorption. Standard prenatal vitamins contain iron, though the amount varies; if levels are low, your provider may recommend additional supplementation. Understanding the broader context of cycle and blood loss patterns can also be relevant when considering baseline iron status before pregnancy.
Omega-3 Fatty Acids (DHA)
Docosahexaenoic acid (DHA), an omega-3 fatty acid found primarily in fatty fish, is an important structural component of the fetal brain and retina. Research suggests that adequate DHA during pregnancy may be associated with aspects of neurological development, though the optimal intake and supplementation approach are still areas of active study.
The American College of Obstetricians and Gynecologists suggests that pregnant women aim for at least 200 mg of DHA per day. Fatty fish such as salmon, sardines, and trout are among the richest dietary sources. Fish oil or algae-based DHA supplements are options for those who don’t consume fish regularly. (Note: high intake of certain fish—particularly those with high mercury content—is generally discouraged during pregnancy; your provider can guide appropriate choices.)
Calcium and Vitamin D
Calcium supports fetal bone development and helps maintain maternal bone density during pregnancy. The recommended intake is 1,000 mg per day during pregnancy. Dairy products, fortified plant milks, leafy greens, and canned fish with bones are common dietary sources. If dietary intake is insufficient, supplementation may be appropriate.
Vitamin D works in concert with calcium and supports immune function, fetal bone development, and potentially other aspects of pregnancy health. Deficiency is common in many populations, and for women over 35—who may have had limited sun exposure or specific dietary patterns—checking vitamin D status through a blood test before or during pregnancy can be informative. Your provider can recommend supplementation based on your baseline level and dietary intake.
Choline
Choline is a nutrient that doesn’t receive as much attention as folate, but research suggests it plays an important role in fetal brain development and may work synergistically with folate in supporting neural tube health. Adequate intake during pregnancy is 450 mg per day. Eggs, beef liver, salmon, chicken, and cruciferous vegetables are among the better dietary sources.
Many prenatal vitamins contain little or no choline, which means it often needs to be obtained primarily through diet or separate supplementation. Discussing choline status with your provider or a registered dietitian is worthwhile, particularly if your diet is plant-based. For additional context on how nutrition intersects with overall reproductive health, exploring nutrition and fertility after 35 may offer useful perspective.
Iodine
Iodine supports thyroid function in both mother and fetus, and adequate intake is essential for fetal neurological development. The recommended intake during pregnancy is 220 micrograms per day. Iodine is found in seafood, dairy products, and iodized salt; it’s also typically included in prenatal vitamins, though not all formulations contain it. Checking that your prenatal vitamin includes iodine is a simple verification step.
How to Approach Prenatal Nutrition Practically
The practical reality of prenatal nutrition is that no one eats perfectly, especially during the first trimester when nausea and food aversions are common. A high-quality prenatal vitamin provides a safety net for most micronutrient needs—but it works best as a complement to a varied, whole-food diet rather than a replacement for one.
Some practical approaches that may be helpful:
- Begin taking a prenatal vitamin before conception, ideally at least one month before trying to conceive
- Work with a registered dietitian if you have dietary restrictions (vegan, vegetarian, food allergies) that may affect nutrient intake
- Discuss any supplements you’re taking with your OB/GYN or midwife—some supplements are not appropriate during pregnancy
- Focus on variety and adequacy rather than perfection, especially during periods of nausea
Frequently Asked Questions
When should I start taking prenatal vitamins?
Current guidance recommends starting prenatal vitamins before conception—ideally at least one month prior—because folic acid’s protective effect against neural tube defects is most critical in the first 28 days of pregnancy, often before a woman knows she is pregnant. If you’re trying to conceive, beginning prenatal vitamins now is generally recommended.
Are there nutrients I need more of after 35 specifically?
Prenatal nutritional recommendations are largely consistent across reproductive age groups, as they focus on fetal needs rather than maternal age. However, some women over 35 may have lower baseline levels of certain nutrients—such as iron (due to heavier periods) or vitamin D—making it worth checking levels before or early in pregnancy.
Is it safe to take supplements during pregnancy beyond a prenatal vitamin?
This varies by supplement. Many supplements that seem benign—including herbal products, high-dose vitamins, and some minerals—are not well-studied in pregnancy and may carry risks. Your healthcare provider should know about any supplements you’re taking, and it’s best to discuss the addition of any new supplement before starting it during pregnancy.
What if nausea makes it hard to eat during the first trimester?
First-trimester nausea is extremely common and can make meeting nutritional targets very difficult. The focus during this period is typically on eating whatever is tolerable, staying hydrated, and continuing prenatal vitamins as tolerated (some women find taking them at night or with food helps). Your provider can discuss additional approaches if nausea is severe (hyperemesis gravidarum).
Key Takeaways
- Folate, iron, DHA, calcium, vitamin D, choline, and iodine are among the most important nutrients during pregnancy and the preconception period
- A high-quality prenatal vitamin is universally recommended, ideally started before conception; it works best alongside a varied, whole-food diet
- Women over 35 may benefit from checking baseline nutrient levels (particularly iron and vitamin D) before or early in pregnancy
- Any supplements beyond a prenatal vitamin should be discussed with a healthcare provider before use during pregnancy
- A registered dietitian can provide personalized nutritional guidance based on dietary patterns, health history, and pregnancy-specific needs
Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice. Individual health situations vary significantly. Always consult a qualified healthcare provider before making decisions related to your health, fertility, or pregnancy.
About the Author
Emily Carter is a women’s health writer focused on fertility, pregnancy after 35, and sleep changes in midlife. She writes research-informed, non-alarmist content to help women navigate reproductive and hormonal transitions with clarity and confidence.