Percent of women of reproductive age with anemia
The percent of women ages 15 to 49 screened for hemoglobin levels who have inadequate levels. Pregnant women with a hemoglobin level less than 11g/dl and non-pregnant women with a level less than 12g/dl are considered anemic (WHO, 2001; WHO, 2006).
This indicator is calculated as:
(Number of women ages 15 to 49 with inadequate hemoglobin levels[<12 g/dl non-pregnant women and <11g/dl pregnant women] / Total number of women ages of 15 to 49 screened for hemoglobin levels during a specified period) x 100
WHO (2000) has defined anemia as mild, moderate, or severe based on the following cutoff values (g/dl) for hemoglobin level:
*The level of anemia termed ‘mild’ is still a serious condition given iron deficiency is already advanced by the time anemia is detected and deficiency can have functional consequences even when anemia is not clinically apparent (WHO, 2000).
For population-level analyses, evaluators may use mean hemoglobin level (a continuous variable) instead of the above categories of mild, moderate, or severe anemia.
Hemoglobin concentration measures on a sample of women of reproductive age including both pregnant and non-pregnant women (population based survey, surveillance system, or health facility clients). The gold standard for assessing hemoglobin is the direct cyanomethhemoglobin method, which requires access to a laboratory. However, indirect methods using a finger-prick blood sample can be administered as a low technology alternative (WHO, 2006). In areas where resources are lacking for the test kits, antenatal care (ANC) clinics can screen for anemia by clinical examination using a WHO developed color scale comparing the shade or color shade of blood with defined hues of red(WHO, 2006). Data should be provided with indications of the source (e.g., clinical records, surveys) and the method used for hemoglobin assessment in order to allow for comparisons, when needed.
Data can be disaggregated by age groups, parity, reproductive status (pregnant, lactating, and non-pregnant, non-lactating), trimester of pregnancy, level of severity of anemia, and where available, by relevant socioeconomic and demographic factors such as education, income, and urban/rural residence. In addition, altitude can affect hemoglobin levels and may warrant disaggregation or adjustments where wide ranges in altitude exist for a given population (WHO, 2001).
Population-based surveys (e.g., DHS, RHS, UNICEF Multiple Indicator Cluster Surveys); surveillance (WHO Vitamin and Mineral Information system); health facility data and ANC records.
Anemia is a condition in which an inadequate number of red blood cells or an inadequate amount of hemoglobin impairs blood oxygen transport resulting in reduced physical and mental capacity. Hemoglobin is the red-pigmented protein in red blood cells that carries oxygen to the brain, muscular system, immune system, and other parts of the body. Iron, folic acid, and other vitamins and minerals (micronutrients) are required for the formation of hemoglobin. Nutrition deficiencies are the most common causes for anemia and iron deficiency anemia is a major contributor to the global burden of disease (WHO/CDC, 2008). In addition to iron, other nutritional deficiencies (e.g., folate, vitamin B-12, and vitamin A) can cause anemia, as can non-nutritional factors such as acute and chronic infections (malaria, hookworm, HIV) and genetic conditions such as thalassemia and sickle cell trait. This indicator relates to achieving three of the Millennium Development Goals: #1. Reduce poverty and hunger; #4. Reduce child mortality; and #5. Improve maternal health.
Among women of reproductive age, adolescent girls and pregnant women are at most risk for anemia: adolescents because of the onset of menstruation and pregnant women because of the increased blood volume associated with pregnancy. Based on a WHO review of nationally representative samples from 1993 to 2005, 42 percent of pregnant women have anemia, and 60 percent of this anemia is assumed to be due to iron deficiency in non-malarial areas and 50 percent in malarial areas (WHO/CDC, 2008). In industrialized countries anemia also affects women, especially those of lower socioeconomic status. Iron deficiency is the primary cause of most anemia in low-income environments. Severe anemia among pregnant women resulting from iron deficiency is associated with an increased risk of maternal and fetal mortality and morbidity and of intrauterine growth retardation (WHO, 2000; WHO/CDC, 2008).
The initial use for this indicator is to identify women with anemia who require iron supplementation and complementary care. It can be used as a proxy for general nutritional status. Population-based assessments can estimate prevalence of anemia and iron deficiency in communities and regions; identify high-risk populations for intervention; monitor prevention or treatment programs; and identify need and advocate for food fortification and iron supplementation programs. For surveillance purposes, rapid assessments of anemia are conducted each year and population–level surveys every five years (WHO, 2006).
This indicator is also useful for monitoring sub-populations (e.g., pregnant women, lactating women, women who receive ANC, women who receive postpartum care) and for evaluating interventions directed towards these subgroups.
Various factors may influence estimates of anemia prevalence, including sex, age, pregnancy status, smoking status and altitude. Atmospheric oxygen levels fall with increasing altitude, thereby leading to higher blood hemoglobin levels. Evaluators should adjust individual-level for data long-term altitude exposure (see WHO, 2001, Annex 3 for altitude adjustment values).
Low hemoglobin levels may be due to multiple causes, such as, short birth intervals, blood loss, or illnesses that are not nutrition related. Additional laboratory tests, such as measurement of serum ferritin and/or malarial and parasitic egg counts, are necessary to determine if iron deficiency is the primary cause of the anemia. However, these tests are frequently impractical for field-based use. Until a simple, cost-effective test for measurement of iron deficiency is widely available for program and field applications, the prevalence and distribution of anemia will continue to be used to estimate the extent, trends, and severity of both anemia and iron deficiency anemia at the population level.
Women attending ANC may be a self-selected group and not representative of all pregnant women in an area. They may be more likely to have health problems or to be more affluent, educated, and/or urban. If data sources are from routine ANC screening, caution should be used in interpreting and generalizing results.
nutrition, newborn (NB), malaria, safe motherhood (SM)
There may be gender-related food taboos that contribute to high levels of anemia by denying women iron-rich foods (meat, eggs, and dairy). In addition, social norms may dictate the order in which family members eat, thus limiting women’s (especially girls and young women) access to iron-rich foods. It may be difficult for women to obtain iron/folate supplements if they lack freedom of movement to travel to distribution points or lack access to household financial resources for transportation to distribution points or to purchase commodities.
WHO, Vitamin and Mineral Information System (VMNIS), Department for Health and Development (NHD), Geneva, Switzerland. Online database at http://www.who.int/vmnis/en/
WHO, 2000, The management of nutrition in major emergencies, Geneva: WHO.
WHO, 2001, Iron deficiency anaemia, assessment, prevention, and control: A guide for program managers, Geneva: WHO.
WHO, 2006, Reproductive health indicators; guidelines for their generation, interpretation, and analysis, Geneva: WHO. http://apps.who.int/iris/bitstream/10665/43185/1/924156315X_eng.pdf
WHO/CDC. 2008. Worldwide prevalence of anaemia 1993–2005 : WHO global database on anaemia. De Benoist B, McLean E, Egli I, Cogswell M eds. World Health Organization, Geneva. Available at http://whqlibdoc.who.int/publications/2008/9789241596657_eng.pdf