Nowadays, the living conditions are better, and the pregnant mothers-to-be have good food and drink every day, but there are still many pregnant women who are found to be anemic during physical examination. Let’s learn more about anemia.
Definition and classification of anemia in pregnancy WHO recommends that hemoglobin Hb <110g/L in pregnancy can be diagnosed as combined anemia in pregnancy. Anemia can be classified as mild anemia 100-109g/L, moderate anemia 70-99g/L, severe anemia 40-69g/L, and very severe anemia <40g/L. The significance of setting the grading is to pay attention to anemia in pregnancy because of the presence of hemorrhage in obstetrics.
Iron deficiency anemia in pregnancy is defined as anemia due to iron deficiency during pregnancy with Hb <110g/L.
Severe anemia is relatively rare in clinical practice, and most of them are mild anemia. In mild anemia, there is no obvious clinical manifestation, fatigue is more common, and in severe anemia, pallor, weakness, palpitations, dizziness, dyspnea and irritability can occur. iron stores can be depleted before Hb drops, so iron deficiency manifestations such as fatigue, irritability, loss of concentration and hair loss can occur even before anemia occurs. In areas with high prevalence of thalassemia, such as Guangdong, Guangxi, Hainan, Hunan, Hubei, Sichuan and Chongqing, routine screening for thalassemia should be performed at the first prenatal visit.
Guidelines recommend.
1, iron therapy trial is preferred for patients with anemia of small cell hypochromia, and an elevated Hb after 2 weeks of treatment is suggestive of IDA. those who are ineffective with iron therapy should undergo differential diagnosis.
2, those who are ineffective with iron therapy should be further examined for impaired absorption, poor compliance, blood loss and folic acid deficiency, and referred to a higher level of care.
3.Regions with a high prevalence of thalassemia, such as the two provinces, the two lakes, Sichuan and Chongqing, should be routinely screened for thalassemia during the first prenatal checkup.
4.Medical institutions with conditions should test serum ferritin for all pregnant women.
5.Pregnant women with hemoglobinopathies should be tested for serum ferritin.
6.The detection of C-reactive protein is helpful for differential diagnosis of increased serum ferritin due to infection.
Treatment recommendations.
1. General principles of iron deficiency and mild to moderate anemia: take oral iron mainly, improve diet, and eat iron-rich foods. Severe anemia: take oral or injectable iron, and in some cases near delivery or affecting the fetus, a small amount of concentrated red blood cells can be transfused several times. Extremely severe anemia: transfusion of concentrated red blood cells is preferred, until Hb>70g/L. After the symptoms are relieved, it can be changed to oral or injectable iron. after Hb is restored to normal, oral iron should be continued for 3-6 months, or until 3 months after delivery.
2, diet dietary iron absorption rate of pregnant women is 15%, the physiological need for iron of pregnant women is 3 times higher than the amount of menstruation, and increases with the progress of pregnancy, the need for iron intake 30mg/d in the middle and late pregnancy. iron intake and iron absorption can be increased through dietary guidance. Ninety-five percent of dietary iron is non-heme iron.
Foods that contain heme iron are red meat and poultry. Foods that promote iron absorption are fruits, potatoes, green leafy vegetables, cauliflower, carrots and cabbage that contain vitamin C. Some foods inhibit iron absorption, such as milk and milk products, cereal bran, cereals, high gluten flour, beans, nuts, tea, coffee, cocoa.
3, iron pregnant women’s iron stores depleted, only through food is difficult to replenish enough iron, need to supplement iron. Oral iron supplementation is effective, inexpensive and safe. Diagnosed IDA pregnant women should be supplemented with elemental iron 100-200mg / d. Pregnant women with hemoglobinopathy can be given oral iron if their serum ferritin is less than 30ug / L.
(1) Usage of oral iron: For the treatment of diagnosed IDA, pregnant women should supplement with elemental iron 100-200mg/d and recheck Hb after 2 weeks to assess the efficacy. Usually the Hb increases by 10 g/L after 2 weeks and by 20 g/L after 3-4 weeks. non-anemic pregnant women with serum ferritin <30ug/L should consume elemental iron 60mg/d and assess the efficacy after 8 weeks.
(2) Side effects of oral iron: about 1/3 of patients taking oral iron have dose-related adverse reactions. Gastrointestinal symptoms such as nausea and epigastric discomfort are easily seen with elemental iron supplementation ≥200 mg/d.
There are many commonly used oral iron supplements, and the most commonly used now is polysaccharide iron complex. It is recommended to take iron orally 1h before eating, together with vitamin C to increase the absorption rate. Avoid taking it at the same time with other drugs.
(3) Injectable iron: Those who cannot tolerate oral iron, whose compliance is uncertain or whose oral iron is ineffective can choose injectable iron. Injectable iron can cause a rapid and sustained increase in Hb levels, and its efficacy is better than oral ferrous sulfate. There are many commonly used iron supplements; iron sucrose is currently considered the safest, and iron dextran may have serious adverse effects.
(4) Guidelines recommend that all pregnant women be given dietary guidance to maximize iron intake and absorption. Once stored iron is depleted, it is difficult to replace sufficient iron through food alone and iron supplementation is usually required. Treatment of pregnant women with a clear diagnosis of IDA should be supplemented with elemental iron 100-200 mg/d, and the efficacy should be assessed by rechecking Hb after 2 weeks of treatment. Treatment until Hb returns to normal should be continued with oral iron for 3-6 months or until 3 months after delivery. Non-anemic pregnant women with serum ferritin <30ug/L should receive elemental iron 60mg/d and the efficacy should be assessed after 8 weeks of treatment. Pregnant women with hemoglobinopathies who have serum ferritin <30ug/L may be given oral iron. It is recommended to take iron orally 1h before eating, together with vitamin C to increase the absorption rate. Avoid concomitant administration with other medications. Lower iron content preparations may reduce gastrointestinal symptoms. Those with obvious anemia symptoms, or Hb <70g/L, or 34 weeks of gestation, or those who have failed to take oral iron should be referred to higher level medical institutions.
4. Blood transfusion is recommended when maternal Hb <60g/L, and when Hb 60-70g/L is decided according to factors such as whether the patient is operated or not and heart function. Because anemic pregnant women have a low tolerance for blood loss, blood transfusion should be given as early as possible if significant blood loss occurs during labor. Those with high risk factors for bleeding should have blood prepared prenatally or transfused preoperatively. Written informed consent should be obtained for all blood transfusions.
Prevention and Screening.
Blood tests should be performed on all pregnant women at the first maternity visit (preferably within 12 weeks of gestation) and repeated every 8-12 weeks thereafter. Routine blood tests are the initial screening test to determine anemia, and serum ferritin can be tested if available.