Iron Deficiency Anemia in Pregnancy: Status and Contributing Factors Among Women in Northern Asir, Saudi Arabia

Summary

This study assessed the prevalence and risk factors of iron deficiency anemia among pregnant women in Bisha, Saudi Arabia. IDA was common during the second trimester and associated with rural residence, family history, and low intake of red meat, poultry, and citrus fruits. Affected women commonly experienced fatigue and dizziness.

Abstract

Iron deficiency anemia (IDA) is a common nutritional disorder during pregnancy and is linked to adverse maternal and fetal outcomes. Beyond hematological markers, understanding related sociodemographic, dietary, and clinical factors is important for prevention.

This study aimed to assess iron status and examine associations between sociodemographic characteristics, dietary habits, clinical factors, and IDA among pregnant women in Bisha, Saudi Arabia. A cross-sectional study was conducted from December 2022 to May 2023 at the Maternity and Children’s Hospital in Bisha. The study included 135 pregnant women and 65 non-pregnant controls. Data was collected using a validated questionnaire covering demographics, diet, and clinical history. Blood samples were analyzed to measure hemoglobin, serum iron, ferritin, total and unsaturated iron-binding capacity, and transferrin saturation. Multivariate logistic regression identified independent risk factors for IDA. IDA was highly prevalent among pregnant women, particularly in the second trimester. Compared with controls, affected women had lower hemoglobin, serum iron, ferritin, and transferrin saturation, and higher iron-binding capacity. Lower intake of red meat, poultry, and citrus fruits, rural residence, and family history of anemia were independently associated with IDA. Fatigue and dizziness were more common among affected women.

Introduction

Anemia is defined as a reduction in hemoglobin concentration, which in severe cases compromises oxygen delivery to vital organs¹. It affects individuals across all age groups, although infants and pregnant women are particularly vulnerable¹. Mild anemia may remain asymptomatic, whereas moderate to severe forms commonly present with fatigue, weakness, dizziness, and pallor. When left untreated, anemia is associated with reduced physical capacity, impaired cognitive development, increased susceptibility to infections during childhood, and unfavorable maternal and fetal outcomes during pregnancy^2,3. Iron deficiency anemia (IDA), the most common type of anemia, arises from depleted iron stores that result in diminished hemoglobin synthesis^4,5. It is recognized as the most prevalent nutritional disorder worldwide and in the Eastern Mediterranean Region (EMR), according to the World Health Organization (WHO)⁶. An estimated 149 million individuals in the EMR are affected by iron deficiency or anemia, including approximately 83 million women^6,7. In the Gulf countries, the prevalence of anemia among women of reproductive age ranges from 15% to 48%⁸. In Saudi Arabia, IDA represents a major public health concern, with reported prevalence rates ranging from 28% to 42%⁹. A survey conducted among schoolgirls in Riyadh reported a prevalence of 40.5% among adolescents aged 16–18 years¹⁰. Reducing the burden of IDA among women of childbearing age remains a critical health priority, as it is strongly associated with increased maternal morbidity, prenatal mortality, and adverse fetal outcomes^4,5.

Globally, anemia has received considerable attention within public health initiatives. WHO and the United Nations International Children's Emergency Fund (UNICEF) established targets to eliminate iron deficiency by the year 2000, and the 1992 International Conference on Nutrition emphasized reducing IDA among women of reproductive age by one-third compared with 1990 levels^6,11. Despite these international efforts, IDA continues to represent a significant health challenge, particularly in low- and middle-income countries where nutritional deficiencies and limited access to healthcare services are common. The etiology of IDA is multifactorial. Inadequate consumption of iron-rich foods remains a leading cause globally and is often compounded by reduced iron absorption due to dietary inhibitors such as tea^12,13. Among women of reproductive age, excessive menstrual blood loss is a frequent contributing factor, while gastrointestinal disorders are more commonly implicated in postmenopausal women and men¹⁴. During pregnancy, increased physiological iron requirements further increase the likelihood of deficiency, particularly when iron stores prior to conception are insufficient^6,11.

Local evidence underscores the burden of IDA in Saudi Arabia; however, most studies have focused on children, adolescents, or women in general rather than specifically on pregnant women. A recent study conducted in Bisha reported high rates of anemia among children under 10 years of age and among females, but pregnant women were excluded from the analysis¹⁵. This gap in evidence is notable, as pregnancy is a period of increased vulnerability to iron deficiency, with important implications for both maternal and neonatal health¹⁶. Given the magnitude of the problem and the limited research focused on pregnant women in the Northern Asir region, further investigation is needed. Examining the prevalence of IDA in this population and identifying factors associated with it, such as age, education, place of residence, dietary practices, and family history, is important for informing appropriate prevention and intervention strategies.

Based on the high burden of IDA reported among pregnant women in Saudi Arabia and the influence of sociodemographic, dietary, and obstetric factors on maternal iron status, this study hypothesized that iron deficiency anemia is highly prevalent among pregnant women in Northern Asir and is associated with modifiable nutritional and demographic risk factors. Accordingly, the present study aimed to assess iron status and examine factors associated with iron deficiency among pregnant women attending the Maternity and Children’s Hospital in Bisha, Northern Asir, Saudi Arabia.

Protocol

Ethical statement: The study was performed in accordance with the institutional guidelines and the ethical principles of the Declaration of Helsinki. Ethical approval was obtained from the Ethical Committee of Bisha University (UBCOM-RELOC), with approval number H-06-BH-087/(0802.23). Participation was voluntary, and written informed consent was obtained from all participants prior to enrollment. The materials, equipment, and analytical procedures used in the study are summarized in the Table of Materials.

Study design and setting
A retrospective cross-sectional study was conducted at the Maternity and Children’s Hospital in Bisha, Saudi Arabia, between December 2022 and May 2023 to assess iron status and examine factors associated with iron deficiency among pregnant women in the Northern Asir Region.

Study population and sampling methodology
A total of 200 participants were enrolled, including 135 pregnant women attending routine antenatal care clinics and 65 age-matched non-pregnant women who served as a control group. Participants were recruited from outpatient clinics via convenience sampling during the study period. Eligible women presenting during clinic hours were consecutively approached, and recruitment continued until the target sample size was reached. To reduce potential selection bias within this framework, controls were age-matched using simple random sampling from eligible non-pregnant clinic attendees.

Pregnant women were eligible for inclusion if they were aged 18 years or older and had a pregnancy with a gestational age between 12 and 36 weeks. Eligible participants were enrolled regardless of their iron status and subsequently classified as pregnant women with IDA or without IDA based on laboratory findings. According to the WHO criteria, anemia during pregnancy was defined as hemoglobin (Hb) concentrations < 11.0 g/dL during the first and third trimesters and < 10.5 g/dL during the second trimester. IDA was diagnosed in women who met the pregnancy-specific Hb threshold and had evidence of iron deficiency, including serum ferritin < 15 ng/mL, serum iron < 10 µmol/L, and total iron-binding capacity (TIBC) ≥ 68 µmol/L^17,18. Pregnant women who did not meet these diagnostic criteria were classified as the pregnant without IDA group. Non-pregnant women of reproductive age with no current pregnancy and without known hematological disorders served as the control group. Exclusion criteria for both groups included a documented history of chronic or systemic conditions associated with altered iron metabolism or inflammatory status, such as chronic kidney disease, autoimmune disorders, malignancy, inflammatory bowel syndrome, chronic liver disease, or hereditary iron disorders (e.g., hemochromatosis). Women with acute infections at the time of sampling, those who had received intravenous iron therapy or blood transfusions within the preceding three months, and those receiving long-term immunosuppressive therapy were also excluded. Body mass index (BMI) and ethnicity were recorded for all participants; however, these variables were not used as exclusion criteria and were instead considered as potential covariates in the analysis.

Sample size determination
The sample size was calculated using an epidemiological sample-size calculation software¹⁹, based on an anticipated prevalence of IDA among pregnant women in Saudi Arabia of 40%⁶, with a 95% confidence level and a 5% margin of error. The minimum required sample size was estimated at 182 participants; therefore, a total of 200 participants were recruited to enhance statistical precision.

Data collection
Questionnaire
Data was collected using a structured and validated questionnaire. The questionnaire was developed following an extensive review of the literature and was evaluated by a panel of subject experts, including obstetricians, nutritionists, and epidemiologists, to ensure content validity. A pilot study involving 20 participants, who were not included in the final analysis, was conducted to assess clarity, reliability, and feasibility. The internal consistency of the questionnaire was acceptable, with Cronbach’s alpha of 0.81.

The final questionnaire consisted of three sections comprising a total of 35 items (Supplementary File 1):

Section 1 (Sociodemographic data, 10 items): age, education level, occupation, place of residence, nationality, and family history of anemia.

Section 2 (Dietary habits, 12 items): frequency of consumption of iron-rich foods (red meat, white meat, fish, vegetables, and fortified cereals), tea and coffee intake, and dietary regimen. Dietary variables were selected a priori based on their established relevance to iron intake, iron bioavailability, and dietary factors that may influence iron absorption. The questionnaire included major dietary sources of iron, including red meat, poultry, fish, green leafy vegetables, and fortified cereals. Vitamin C-rich foods, particularly citrus fruits, were assessed because vitamin C can enhance the absorption of non-heme iron. In contrast, tea and coffee consumption were assessed because dietary polyphenols may inhibit non-heme iron absorption when consumed with or near meals. Dietary regimen and fast-food consumption were also assessed to indicate overall dietary patterns and nutritional adequacy. The selected dietary items were informed by literature reviewed during questionnaire development and were subsequently evaluated by obstetric, nutrition, and epidemiology experts for content validity.

Section 3 (Clinical history and symptoms, 13 items): gestational age, parity, history of blood transfusion, fatigue, dizziness, fever, and other symptoms commonly associated with anemia.

Biochemical assessment
For each participant, a 5 mL venous blood sample was obtained after an overnight fast. Samples were centrifuged at 2000 × g for 15 min to separate the serum, which was subsequently analyzed immediately. Hemoglobin concentration was measured using an automated hematology analyzer and reported in grams per deciliter (g/dL). Serum ferritin levels were assessed using an electrochemiluminescence immunoassay (ECLIA) on an automated immunoassay analyzer and expressed in nanograms per milliliter (ng/mL). Serum iron, total iron-binding capacity (TIBC), and unsaturated iron-binding capacity (UIBC) were determined using a colorimetric method on an automated biochemical analyzer, with results reported in micromoles per liter (µmol/L). Transferrin saturation (TR-SAT) was calculated as the ratio of serum iron to TIBC multiplied by 100 and expressed as a percentage.

Statistics and data analyses
Data was coded and analyzed using standardized statistical analysis software. Descriptive statistics, including means, standard deviations, and percentages, were used to summarize sociodemographic, dietary, clinical, and biochemical variables. Group comparisons were conducted using an unpaired Student’s t-test or one-way analysis of variance (ANOVA), as appropriate. Statistical significance was defined as p < 0.05. Graphical outputs were produced using graphing and statistical software.

To examine factors independently associated with IDA, a multivariate logistic regression model was applied. IDA status was specified as the binary dependent variable (IDA = 1, non-IDA/control = 0). Independent variables were selected a priori based on biological plausibility and evidence from previous studies and included sociodemographic characteristics (residence, family history of anemia), physiological status (pregnancy), and dietary variables (intake of red meat, poultry, and citrus fruits).

Categorical variables were coded using dummy variables, and dietary intake variables were classified as low or adequate based on reported consumption frequency (≤2 times per week vs. >2 times per week). All selected variables were entered simultaneously into the regression model to estimate their independent associations while accounting for potential confounding factors. Adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were reported, where ORs greater than 1 reflected a higher odds of IDA. A visual summary of the ORs and corresponding 95% CIs was presented using a forest plot generated in spreadsheet software.

Results

Study population and participant characteristics
A total of 200 women were enrolled in the study, including 135 pregnant women and 65 non-pregnant controls. Among the pregnant women, 91 (67.4%) were diagnosed with IDA, while 44 (32.6%) had no evidence of IDA.

Questionnaire-based findings
Sociodemographic characteristics
Among pregnant women with IDA, the majority were aged 20–40 years (57.1%), followed by those aged 18–20 years (22...

Discussion

Iron deficiency anemia (IDA) remains a major global public health concern, particularly among pregnant women. Physiological changes during pregnancy, including plasma volume expansion and increasing fetal iron requirements, contribute to declining maternal iron status as gestation progresses. Maternal plasma volume typically increases by approximately 40–50%, resulting in physiological hemodilution and reduced hemoglobin concentration despite an increase in total red blood cell mass. This adaptive response decrease...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
5 mL Vacutainer Blood Collection Tubes	Becton, Dickinson and Company (BD), Franklin Lakes, NJ, USA	https://www.bd.com/en-us/products-and-solutions/products?query=5+mL+Vacutainer+Blood+Collection+Tubes	Used for venous blood sample collection.
Cobas 8000 Modular Analyzer	Roche Diagnostics, Basel, Switzerland	Cobas 8000	Used for serum ferritin, serum iron, TIBC, and UIBC analyses.
Ferritin ECLIA Reagent Kit	Roche Diagnostics, Basel, Switzerland	https://diagnostics.roche.com/global/en/products/lab/elecsys-ferritin-cps-000468.html	Electrochemiluminescence immunoassay for serum ferritin determination.
GraphPad Prism	GraphPad Software, San Diego, CA, USA	Version 9	Used for graphical presentation of results.
IBM SPSS Statistics	IBM Corporation, Armonk, NY, USA	Version 26.0	Used for statistical analyses.
Iron Colorimetric Reagent Kit	Roche Diagnostics, Basel, Switzerland	https://custombiotech.roche.com/global/en/products/cb/iron-bio-ht-3810349.html	Used for serum iron measurement.
Laboratory Centrifuge	Hospital Clinical Laboratory	N/A	Used to separate serum at 2000 × g for 15 min.
Microsoft Excel	Microsoft Corporation, Redmond, WA, USA	Microsoft 365 (or applicable version)	Used to generate the forest plot and organize study data.
OpenEpi Version 3.01	OpenEpi	Version 3.01	Used for sample size calculation.
Structured questionnaire (Supplementary File 1)	Developed by the authors	N/A	Questionnaire developed specifically for this study to collect sociodemographic, dietary, and clinical data.
Sysmex XN-1000 Hematology Analyzer	Sysmex Corporation, Kobe, Japan	XN-1000	Used for hemoglobin measurement.
TIBC/UIBC Colorimetric Reagent Kit	Roche Diagnostics, Basel, Switzerland	https://diagnostics.roche.com/global/en/products/lab/uibc-cps-000266.html	Used for determination of TIBC and UIBC.