The early months of pregnancy can feel like a whirlwind of excitement, change, and (let’s be honest) new challenges. Between navigating food aversions, unpredictable energy levels, and morning sickness, it’s not always easy to eat the perfectly balanced meals you imagined when you first saw that positive test.
And yet, this is one of the most important times to nourish your body. The first and second trimesters are when baby’s brain, bones, and vital organs are forming all while your own body adapts to pregnancy by increasing blood volume, building the placenta, and supporting new hormone patterns. All of this requires a steady supply of key nutrients.
That’s where a comprehensive prenatal vitamin comes in. It’s not meant to replace real food, but it does act as your daily safety net, making sure you and your baby aren’t missing the essentials when cravings and nausea get in the way. I find that when moms have this foundation of nutrient support, it reduces stress and builds confidence, knowing that their body and baby are getting what they need, even on the tough days.
Why nutrients matter in early pregnancy
The first and second trimesters are a period of rapid biological change for both mom and baby. Here’s what’s happening behind the scenes:
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Blood volume expands by up to 50%. This extra blood supplies oxygen and nutrients to the placenta and developing baby.
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The placenta is forming. As the connection between mother and baby, the placenta requires an enormous amount of energy and nutrients to build and maintain.
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Baby’s organs and brain are developing. During the first 20 weeks, nearly every major organ system is established, and the brain begins its complex growth.
Because of these demands, the body’s requirements for key nutrients like iron, iodine, zinc, and magnesium increase substantially. Research shows that deficiencies in early pregnancy can impact both maternal health (fatigue, anemia, blood pressure changes) and fetal outcomes (growth restriction, developmental delays, preterm birth).
Even with a balanced diet, it can be difficult to meet these needs consistently. Morning sickness, food aversions, and fatigue often limit food variety, making certain nutrients harder to get from diet alone. That’s why a complete prenatal vitamin is so valuable in this stage. It helps bridge the gap between what you’re able to eat and what your body requires, ensuring both you and baby have the resources to thrive.
RELATED: How to choose a prenatal vitamin
Our top 4+ nutrients for the 1st and 2nd trimesters
1. Iron: Oxygen for mom & baby
Iron makes hemoglobin, the protein in red blood cells that carries oxygen throughout your body and to baby. During pregnancy, your blood supply increases dramatically, meaning your iron needs almost double.
Without enough iron, you may develop anemia, which can show up as:
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Fatigue or shortness of breath
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Headaches or brain fog
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Dizziness or weakness
But beyond symptoms, iron deficiency has been linked to more serious risks like preterm birth, low birthweight, and even postpartum mood struggles. That’s why WeNatal for Her includes iron in a gentle, absorbable form. It’s designed to support healthy levels without causing the common constipation or nausea associated with some iron supplements.
In my clinical experience, checking ferritin (your iron stores) early in pregnancy gives us a roadmap. If levels are low, it’s much easier to prevent fatigue and complications by supplementing early rather than playing catch-up later.
2. Zinc: Cell growth & immune support
Think of zinc as a “builder” nutrient. It’s required for cell division, tissue growth, immune function, and even taste and smell. Baby relies on mom’s zinc status, and as pregnancy progresses, mom transfers more zinc through the placenta.
The problem? Most women don’t get enough zinc from diet alone. In fact, it’s estimated that over 80% of women fall short. Zinc deficiency has been linked to growth restriction, poor immune function, and higher risk of preterm birth.
I often notice zinc intake drop when protein foods are hard to tolerate in the first trimester. Foods like pumpkin seeds, lentils, beans, and beef are excellent zinc sources, however, if you’re struggling with nausea or food aversions, these may not be on your plate. That’s why we include zinc in WeNatal for Her. Having zinc in a prenatal acts like a safety net, especially when crackers are the only thing that sounds good.
3. Iodine: Fuel for baby’s brain
Iodine is essential for thyroid hormone production, and the thyroid is the “engine” that regulates metabolism, growth, and development. During pregnancy, your needs for iodine increase significantly, especially during the first and second trimesters when baby’s brain and nervous system are rapidly forming.
Deficiency in iodine has been linked to developmental delays, lower IQ, and thyroid issues in both mom and baby. While seafood and dairy are natural sources of iodine, many women aren’t eating enough of these foods, or are avoiding them during pregnancy.
I see women who need to avoid dairy, or follow a plant-based diet, often at higher risk for iodine deficiency. Having iodine in a prenatal helps makes certain baby’s brain gets the support it needs. WeNatal for Her ensures iodine is part of the formula, helping moms consistently meet daily needs without worry.
4. Magnesium: The multitasker mineral
Magnesium is one of the most important yet overlooked nutrients in pregnancy. It’s involved in over 600 reactions in the body, supporting muscle and nerve function, blood sugar balance, blood pressure regulation, and protein synthesis.
Pregnant women often need more magnesium, but many fall short due to modern diets. Research suggests that adequate magnesium intake may lower the risk of complications like gestational diabetes, preeclampsia, and even preterm labor. It can also play a role in reducing muscle cramps, constipation, and sleep difficulties which are common complaints in early pregnancy.
I’ve seen magnesium supplementation make a noticeable difference in sleep quality and stress resilience. When moms feel rested and calmer, it has a ripple effect on the entire pregnancy experience. WeNatal for Her includes magnesium in gentle, bioavailable forms that support your body without causing digestive upset.
RELATED: Can you take magnesium while pregnant?
Bonus: Molybdenum & morning sickness relief?
Nearly 70% of pregnant women experience nausea and vomiting, often called “morning sickness” (though it can happen any time of day). While hormones are a major factor, some researchers believe that excess sulfite buildup in the body may play a role in triggering nausea.
Molybdenum, a trace mineral, acts as a cofactor for enzymes that help break down sulfites into safer compounds. By supporting this pathway, molybdenum may help reduce some of the nausea burden, though research is still in its early stages. We included molybdenum in WeNatal for Her because it’s a safe, gentle nutrient that may support moms when they need it most.
In practice, I combine nutrient support with lifestyle strategies like eating small, frequent meals, keeping protein-rich snacks handy, and prioritizing hydration.
RELATED: Food aversions and cravings during pregnancy: What to expect and how to cope
Practical tips for the 1st–2nd trimesters
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Start (or continue) a prenatal early. It’s your safety net when food variety is limited.
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Eat what you can tolerate. Even if your meals feel repetitive, focus on protein first, gentle iron sources, and magnesium-rich foods.
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Give yourself grace. Some days you’ll eat beautifully balanced meals; other days it may just be toast and prenatal support. That’s okay.
RELATED: Pregnancy nutrition plan by trimester
A note from WeNatal nutrient support for the first and second trimester
At WeNatal, we believe prenatal nutrition should feel simple, supported, and science-backed. That’s why WeNatal for Her includes the essentials like iron, zinc, iodine, magnesium, and a thoughtful touch of molybdenum to meet the increased demands of early pregnancy. And for those days when nausea or digestive discomfort get in the way, WeNatal Rest + Digest offers additional gentle support to help you feel more comfortable. Your pregnancy is unique, but you don’t have to navigate nutrition alone. We’re here to provide the science-backed foundation you can trust, so you can focus on the joy of what’s ahead.
References
De Benedictis CA, Trame S, Rink L, Grabrucker AM. Prevalence of low dietary zinc intake in women and pregnant women in Ireland. Ir J Med Sci. 2023;192(4):1835-1845. doi:10.1007/s11845-022-03181-w
Fanni D, Gerosa C, Nurchi VM, et al. The Role of Magnesium in Pregnancy and in Fetal Programming of Adult Diseases. Biol Trace Elem Res. 2021;199(10):3647-3657. doi:10.1007/s12011-020-02513-0
Fisher AL, Nemeth E. Iron homeostasis during pregnancy. Am J Clin Nutr. 2017;106(Suppl 6):1567S-1574S. doi:10.3945/ajcn.117.155812
Georgieff MK. Iron deficiency in pregnancy. Am J Obstet Gynecol. 2020;223(4):516-524. doi:10.1016/j.ajog.2020.03.006
Mégier C, Dumery G, Luton D. Iodine and Thyroid Maternal and Fetal Metabolism during Pregnancy. Metabolites. 2023;13(5):633. Published 2023 May 6. doi:10.3390/metabo13050633
Skeaff SA. Iodine deficiency in pregnancy: the effect on neurodevelopment in the child. Nutrients. 2011;3(2):265-273. doi:10.3390/nu3020265
Taylor CE. A novel treatment for "morning sickness": Nausea of pregnancy could be induced by excess sulfite which molybdenum can help alleviate. Med Hypotheses. 2016;95:31-33. doi:10.1016/j.mehy.2016.08.007
Terrin G, Berni Canani R, Di Chiara M, et al. Zinc in Early Life: A Key Element in the Fetus and Preterm Neonate. Nutrients. 2015;7(12):10427-10446. Published 2015 Dec 11. doi:10.3390/nu7125542
Wang H, Hu YF, Hao JH, et al. Maternal Serum Zinc Concentration during Pregnancy Is Inversely Associated with Risk of Preterm Birth in a Chinese Population. J Nutr. 2016;146(3):509-515. doi:10.3945/jn.115.220632
