Fatigue during pregnancy is common enough that it’s easy to dismiss as simply part of the experience. But when tiredness is unusually persistent, alongside symptoms like paleness, shortness of breath, or dizziness, it may point to iron deficiency anemia — one of the more common nutritional concerns providers monitor throughout pregnancy, including for women over 35.
According to the Centers for Disease Control and Prevention, iron needs increase substantially during pregnancy to support increased blood volume and the developing baby, and iron deficiency anemia is one of the more common nutritional deficiencies identified during routine prenatal bloodwork. Estimates of how common iron deficiency is during pregnancy vary by population and how it’s measured, but it is consistently identified as one of the most frequent nutritional concerns in pregnancy globally, which is part of why iron-containing prenatal vitamins are so widely recommended as a baseline preventive measure even before any deficiency is confirmed through bloodwork.
What Research Shows About Anemia in Pregnancy
Research indicates that pregnant women require significantly more iron than they did prior to pregnancy, largely due to the roughly 50% increase in blood volume that typically occurs. Without adequate iron intake or absorption, red blood cell production can’t keep pace, leading to anemia. While age itself is not a direct cause of iron deficiency, some research suggests women with closely spaced pregnancies, prior heavy menstrual bleeding, or certain dietary patterns may enter pregnancy with lower iron stores, regardless of age.
How Screening Typically Works
Routine prenatal bloodwork typically includes a complete blood count (CBC), which measures hemoglobin and hematocrit levels — key indicators of anemia. This is usually checked at the first prenatal visit and again later in pregnancy, often around 24 to 28 weeks, sometimes alongside the same visit where gestational diabetes screening occurs. If levels indicate anemia, additional testing, such as ferritin (a marker of iron stores), may help clarify whether iron deficiency is the underlying cause.
Recognizing Possible Symptoms
Symptoms of iron deficiency anemia can include persistent fatigue beyond typical pregnancy tiredness, pale skin, shortness of breath with mild exertion, dizziness, and sometimes unusual cravings for non-food items (a condition called pica). Because many of these symptoms overlap with normal pregnancy experiences, bloodwork remains the most reliable way to identify anemia rather than symptoms alone.
Nutritional Approaches and Supplementation
For women diagnosed with iron deficiency during pregnancy, healthcare providers often recommend iron supplementation, sometimes at higher doses than what’s included in a standard prenatal vitamin. Dietary sources of iron, including lean meats, beans, leafy greens, and iron-fortified cereals, may also be discussed as part of a broader approach, often alongside vitamin C-rich foods, which can support iron absorption. Because iron supplements can cause digestive side effects for some women, providers may suggest specific formulations or timing strategies to improve tolerance. This is a conversation to have directly with your provider rather than self-prescribing high-dose supplements, since excessive iron intake can also carry risks.
Why Untreated Anemia Matters
Left unaddressed, more significant anemia during pregnancy has been associated in research with increased fatigue, greater risk of needing blood transfusion around delivery, and in some studies, associations with preterm birth or low birth weight, though many of these associations are strongest with more severe, prolonged anemia rather than mild cases. This is precisely why routine screening and follow-up matter — catching and addressing iron deficiency early is generally straightforward and effective.
Iron and the Postpartum Period
Iron considerations don’t necessarily end at delivery. Blood loss during childbirth, even in an uncomplicated delivery, can further deplete iron stores, and postpartum anemia is a recognized concern that sometimes gets less attention than anemia during pregnancy itself. Research has linked postpartum anemia to increased fatigue and, in some studies, associations with mood changes during the postpartum period, which can be difficult to distinguish from the general exhaustion and adjustment that comes with caring for a newborn.
Because postpartum bloodwork isn’t always automatically repeated unless specifically requested, women who were anemic during pregnancy, or who experienced significant blood loss during delivery, may want to ask their provider about rechecking iron levels at their postpartum visit, particularly if fatigue feels more intense or prolonged than expected. This is especially relevant for women over 35, who may already be managing higher demands from balancing recovery with other responsibilities, including caring for older children.
Dietary Continuity After Delivery
For breastfeeding women, iron needs remain elevated compared to pre-pregnancy levels, though generally somewhat lower than during pregnancy itself. Continuing to prioritize iron-rich foods and, if recommended by a provider, continuing supplementation for a period after delivery is a common approach, though the specific duration and dosage should be individualized based on postpartum bloodwork and recovery.
Iron-Rich Foods Worth Knowing
Dietary iron comes in two forms: heme iron, found in animal products like red meat, poultry, and fish, which the body absorbs relatively efficiently, and non-heme iron, found in plant sources like beans, lentils, spinach, and fortified cereals, which is absorbed less efficiently on its own. Pairing non-heme iron sources with vitamin C-rich foods, such as citrus fruits or bell peppers, has been shown in research to improve absorption, which can be a useful strategy for women following vegetarian or largely plant-based diets who want to support their iron intake through food alongside any recommended supplementation.
Frequently Asked Questions
Is anemia more common in pregnancies after 35?
Age itself is not a primary driver of iron deficiency anemia; factors like diet, prior pregnancies, and menstrual history tend to matter more. However, anemia screening is a routine part of prenatal care regardless of age.
How is iron deficiency anemia treated during pregnancy?
Treatment often involves iron supplementation, sometimes at a higher dose than in a standard prenatal vitamin, alongside dietary adjustments. Your provider can recommend an approach based on your specific bloodwork results.
Can I just take extra iron supplements on my own?
It’s best to have iron levels checked and discuss supplementation with your provider, since both too little and too much iron can affect health, and the appropriate dose depends on individual test results.
Will anemia affect my baby?
Most mild anemia, when identified and addressed, does not significantly affect pregnancy outcomes. More significant, untreated anemia has been associated with some risks in research, which is part of why routine screening and follow-up are recommended.
Key Takeaways
- Iron needs increase substantially during pregnancy, and iron deficiency anemia is one of the more common nutritional concerns identified through routine bloodwork.
- Screening typically occurs at the first prenatal visit and again later in pregnancy through standard blood tests.
- Symptoms can overlap with normal pregnancy fatigue, making bloodwork the more reliable way to identify anemia.
- Iron supplementation and dietary adjustments, guided by a healthcare provider, are generally effective at addressing iron deficiency when identified early.
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.