Researchers in Slovakia studied pregnant and postpartum women to understand how vitamin and mineral levels change during pregnancy and after birth. They found that some nutrients like vitamin D stay fairly steady, while others like iron and zinc drop significantly during pregnancy. Vitamin B12 deficiency was surprisingly common, especially in the final three months of pregnancy. The study also showed that a simple finger-prick blood test works just as well as traditional blood draws for checking certain vitamins. These findings help doctors understand which nutrients pregnant women need to watch most carefully.

The Quick Take

  • What they studied: How levels of important vitamins and minerals (like iron, zinc, vitamin B12, and vitamin D) change in women’s blood during pregnancy and after giving birth
  • Who participated: Pregnant women and women who had recently given birth in Slovakia, studied between January and June 2024. The exact number of women wasn’t specified in the abstract
  • Key finding: Several important nutrients drop to concerning levels during pregnancy—especially iron, zinc, and vitamin B12. Vitamin D deficiency was common throughout pregnancy and after birth. Interestingly, vitamin E levels got higher than normal during pregnancy
  • What it means for you: If you’re pregnant or planning to become pregnant, talk to your doctor about checking your iron, zinc, and B12 levels, especially in the final three months of pregnancy. Vitamin D supplements may be worth discussing with your healthcare provider

The Research Details

This was a cross-sectional study, which means researchers took a snapshot of women’s nutrient levels at different points in time—during pregnancy and after birth. They collected blood samples from women in Slovakia between January and June 2024. The researchers measured nine different nutrients and minerals using standard laboratory tests. They also tested whether a simple finger-prick blood test (called a dried blood spot test) could give the same results as traditional blood draws from a vein. This is important because finger-prick tests are easier, cheaper, and less painful than regular blood tests.

Understanding how nutrient levels change during pregnancy is crucial because both the mother and developing baby need adequate vitamins and minerals. If doctors know which nutrients commonly drop during pregnancy, they can screen for deficiencies earlier and prevent problems. The validation of the finger-prick test method is also significant because it could make nutrient screening more accessible to pregnant women in resource-limited areas

This study provides real-world data from an actual population of pregnant women, which is valuable. However, the abstract doesn’t specify how many women were studied, which makes it harder to judge how reliable the results are. The study was published in PLOS ONE, a reputable peer-reviewed journal. The researchers used standard, well-established laboratory methods to measure nutrients, which increases confidence in the accuracy of the measurements

What the Results Show

The study found that nutrient levels change significantly during pregnancy compared to after birth. Iron and zinc levels were noticeably lower during pregnancy, which is concerning because both nutrients are essential for the baby’s development and the mother’s health. Vitamin B12 deficiency was surprisingly common, especially during the third trimester (the final three months of pregnancy), affecting a large percentage of the women studied. Vitamin D deficiency was widespread throughout pregnancy and continued after birth, suggesting many women may need supplementation. In contrast, vitamin E levels actually increased during pregnancy and often exceeded what’s considered normal for non-pregnant adults.

Vitamin A, B6, folate, and homocysteine levels showed various patterns across pregnancy and postpartum. Vitamin D and folate remained relatively stable compared to other nutrients, though vitamin D deficiency was still common. The study also found that zinc levels dropped even further after giving birth, which could affect a mother’s recovery and ability to breastfeed. Magnesium and selenium levels were measured but showed less dramatic changes than iron and zinc

Previous research has documented that pregnancy increases nutrient demands, but this study provides current data from a European population. The high prevalence of vitamin B12 and iron deficiencies aligns with what other studies have found, confirming these are consistent concerns during pregnancy. The finding about vitamin D deficiency is also consistent with global research showing widespread vitamin D insufficiency, particularly in northern European countries with less sun exposure

The abstract doesn’t specify the total number of women studied, making it difficult to assess how representative the findings are. The study was conducted only in Slovakia during a six-month period, so results may not apply to all populations or seasons. The study is cross-sectional, meaning it shows snapshots at different times rather than following the same women throughout pregnancy, which limits our understanding of individual changes. We don’t know if the women were taking supplements, which could affect nutrient levels

The Bottom Line

Pregnant women should discuss nutrient screening with their healthcare provider, particularly for iron, zinc, and vitamin B12 in the third trimester. Vitamin D supplementation may be beneficial, especially for women in northern climates or those with limited sun exposure. These recommendations are based on solid evidence but should be personalized by your doctor based on your individual health status and dietary intake

This research is most relevant for pregnant women, women planning pregnancy, and healthcare providers who care for pregnant women. It’s particularly important for women in Europe or similar climates. Women with dietary restrictions (vegetarians, vegans) should especially pay attention since B12 and iron are harder to get from plant-based foods. However, these findings may not apply equally to all populations, so individual assessment is important

If you start supplementing based on these findings, it typically takes 4-8 weeks to see meaningful improvements in blood nutrient levels. For iron deficiency, it may take 2-3 months to fully correct. The best approach is to get tested early in pregnancy so deficiencies can be addressed before they affect fetal development

Want to Apply This Research?

  • Log your prenatal vitamin and supplement intake daily, noting the specific nutrients (iron, B12, vitamin D, zinc) and dosages. Track any symptoms of deficiency like fatigue, shortness of breath, or poor wound healing
  • Set a daily reminder to take prenatal vitamins at the same time each day. Use the app to log which nutrients you’re supplementing and set a reminder for your next nutrient screening appointment with your healthcare provider
  • Record your blood test results in the app when you get them, tracking iron, B12, vitamin D, and zinc levels across pregnancy and postpartum. Compare results over time to see if supplementation is working. Share this data with your healthcare provider at each visit

This research provides important information about nutrient patterns during pregnancy, but it should not replace personalized medical advice from your healthcare provider. Nutrient needs vary significantly between individuals based on diet, health status, and other factors. Do not start, stop, or change any supplements without discussing it with your doctor or midwife. If you are pregnant or planning to become pregnant, work with your healthcare team to determine which nutrients you specifically need and in what amounts. This study is observational and shows associations, not definitive proof of cause and effect.