Spatio-temporal trends in anaemia among pregnant women, adolescents and preschool children in sub-Saharan Africa

Prevalence and associated factors of anaemia and iron-deficiency anaemia among adolescent Sudanese schoolchildren: a cross-sectional study

Anaemia among adolescents is a worldwide health problem; however, data on anaemia among adolescents in Sudan are scarce. A cross-sectional study was conducted to investigate the prevalence and associated factors of anaemia and iron-deficiency anaemia among adolescent schoolchildren in northern Sudan. Socio-demographic information was collected using a questionnaire. A total of 309 adolescents (52.4% female and 47.6% male) were enrolled in the study. Seventy-five (24.3%) adolescents had anaemia, and none had severe anaemia. In the multivariate analysis, history of pica [adjusted odds ratio (AOR)  =  2.30, 95% confidence interval (CI) = 1.31-4.02] was associated with increased odds of anaemia, and an increased level of serum ferritin (AOR  =  0.97, 95% CI = 0.95-0.99) was associated with decreased odds of anaemia. Of the adolescents, 189 (61.2%) and 55 (17.8%) had iron deficiency and iron-deficiency anaemia, respectively. In the multivariate analysis, being female (AOR  =  3.13, 95% CI = 1.88-5.23) and having a history of pica (AOR  =  1.85, 95% CI = 1.03-3.31) were associated with increased odds of iron deficiency. This study showed a high prevalence of anaemia and iron-deficiency anaemia among adolescents in this part of Sudan, which was associated with a history of pica.

Things seen and unseen: 2. Anaemia affects urban rich Nigerian adolescents more than other socio‑economic status groups

Background: Anaemia is very prevalent globally and is thought to be linearly associated with wealth and to affect females and rural residents more than males and urban residents. Objectives: This study was designed to investigate this thought in a population of adolescents in Ebonyi State, Nigeria. Methods: Standard clinical protocols were used. A total of 362 adolescents (63.5% females) were studied. Anaemia was diagnosed on the basis of the World Health Organization (WHO) criteria. Results: Aggregate anaemia was found in 50.0% of the general population (43.9% males, 53.5% females) and was most prevalent in the urban upper socio‑economic status (SES) group (62.3%; 70.0% females, 52.2% males). Severe anaemia was present in 7.2% of the general population (9.1% males, 6.1% females). It was most prevalent amongst the 10-11 years age bracket (15.6%). Moderate and mild anaemia were found in 22.4% and 20.4% of the general population and in 13.0%, 11.4%, 8.3% and 6.0% of the urban upper, rural, urban low and middle SES groups, respectively. But in the rural area group, severe anaemia existed without wide sex variations. Moderate anaemia was most prevalent in the urban middle and upper SES groups (29.0% and 26.4%, respectively) with a clear female preponderance. Mild anaemia was the least prevalent (15.3%) in the urban middle SES group. Conclusions: The higher prevalence of severe anaemia in boys and the higher burden in the urban higher SES group warrant a rethink of the public health interventions used in Nigeria. Adolescent boys and urban upper SES groups should be targeted in nutrition interventions related to anaemia.

Food-based domestic violence and anemia among women in sexual unions in Nigeria: the effect of urbanization

In 2019, 1.74 billion people worldwide had anemia. In Nigeria, women of reproductive age are the most affected. Domestic violence affects the anemia prevalence, but few studies have examined the influence of urbanization on women in heterosexual unions (currently married, and cohabiting between). Using the social determinants of health framework, we argue that food-based violence and anemia vary among women residing in rural and urban areas. We used the Chi-square test and logistic regression to analyze the 2018 Nigeria Demographic and Health Survey records (n = 10,499). The study showed that anemia occurs more among women in rural (66%) than in urban (34%) areas. In rural areas, anemia was 29% higher among women who approved food-based domestic violence (OR: 1.29, CI 1.15-1.57) than those who did not. In urban areas, food-based domestic violence was not significantly associated with anemia. This study emphasizes the urgent need for culturally sensitive maternal health interventions aimed at re-orienting individuals and families on violence in rural areas.

Intravenous ferric carboxymaltose versus oral ferrous sulphate for the treatment of moderate to severe postpartum anaemia in Nigerian women (IVON-PP): protocol for an open-label randomised controlled type 1 hybrid effectiveness-implementation trial

INTRODUCTION

Postpartum anaemia is often caused by iron deficiency with onset during the antepartum period and can be exacerbated by excessive blood loss at birth. Its prevalence is estimated as 50-80% in low-income and middle-income countries. It poses adverse consequences on the mother and negatively impacts her ability to care for her newborn. Prompt treatment of postpartum anaemia is thus important. Adherence to oral iron is reportedly low in Nigeria due to its side effects and forgetfulness by the mothers. Intravenous iron such as ferric carboxymaltose, given as a single dose, might help overcome adherence issues, but investigation in a high-quality randomised control trial in Nigeria is first required while evaluation of challenges around its implementation is also warranted.

OBJECTIVE

To determine the clinical effectiveness, tolerability and safety, of using intravenous ferric carboxymaltose (intervention) vs oral ferrous sulphate (control) for treating moderate to severe iron deficiency anaemia in postpartum women and to evaluate implementation of ferric carboxymaltose in treating postpartum anaemia in Nigeria.

METHODS AND ANALYSIS

This study is an open-label randomised controlled trial with a concurrent implementation study. It is a hybrid type 1 effectiveness-implementation design conducted in four states across Northern and Southern Nigeria. A total of 1400 eligible and consenting women with postpartum moderate to severe anaemia (haemoglobin concentration <100 g/L) will be randomised to intravenous ferric carboxymaltose; a single dose at 20 mg/kg to a maximum of 1000 mg infusion administered at enrolment (intervention) or oral ferrous sulphate; 200 mg (65 mg elemental iron) two times per day from enrolment until 6 weeks postpartum (control). The primary outcome, proportion of participants who are anaemic (Hb <110 g/L) at 6 weeks postpartum will be analysed by intention-to-treat. Haemoglobin concentration, full blood count, serum iron, serum ferritin, transferrin saturation and total iron binding capacity will be measured at specific intervals. Implementation outcomes such as acceptability and feasibility of using ferric carboxymaltose for postpartum anaemia treatment in Nigeria will be assessed.

ETHICS AND DISSEMINATION

This study is approved by the ethics committee of the teaching hospitals, Ministry of Health of the four states as required, National Health Research Ethics Committee and the drug regulatory agency, National Agency for Food and Drug Administration and Control (NAFDAC). Findings of this research will be presented at conferences and will be published in international peer-reviewed journals and shared with stakeholders within and outside Nigeria.

TRIAL REGISTRATION NUMBER

International standard randomised controlled trial number: ISRCTN51426226.

Microfilariae Prevalence and its Association with Anemia Among First-time Blood Donors in Lambaréné, Gabon

Background

Anemia remains a significant public health concern in Gabon, particularly among children, adolescents, and females. Gabon is also home to two major species of filarial worms, Loa and Mansonella spp., which cause microfilaremia. The epidemiological nexus between hemoglobin (Hb) concentrations and microfilaremia in Gabonese first-time blood donors remains unknown.

Aims

To understand better the epidemiological relationship between anemia and microfilaremia to improve donor selection and management protocols.

Study Design

A retrospective cohort study.

Methods

This study was conducted among first-time blood donors in Lambaréné between March 2018 and October 2019. Participants aged 16-65 years old and weighing a minimum of 50 kg were enrolled using standard donor selection criteria. An automatic hematological analyzer was used to quantify Hb concentrations, and microscopy techniques were used to detect the presence of microfilariae.

Results

Microfilariae were found in 4.8% (35/723) of the 723 first-time blood donors from Lambaréné. Anemia was classified as mild in 35.5% (257/723) and moderate in 1% (7/723). No significant associations were found between the distribution of microfilariae and variables such as age, sex, socioprofessional classification, marital status, or residence. Blood group O donors had a higher prevalence of microfilariae (6%) than non-O donors (2.7%). However, the observed difference was not statistically significant (AOR =2.3, p = 0.052). Furthermore, microfilariae were associated with increased moderate anemia (3.7% vs. 29%, AOR =15.6, p = 0.003).

Conclusion

Our findings highlight microfilaremia as a possible etiological cause of anemia among Gabonese blood donors, emphasizing the need for further research and a potential review of donor management strategies.

Determinants of anemia level among reproductive-age women in 29 Sub-Saharan African countries: A multilevel mixed-effects modelling with ordered logistic regression analysis

BACKGROUND

Despite the implementation of different nutritional and non-nutritional interventions, 43% of reproductive-age women in Africa suffer from anemia. Recent evidence also shows that none of the Sub-Saharan African (SSA) countries are on the track to achieve the nutrition target of 50% anemia reduction by 2030. To date, information on the level of anemia and its determinants among reproductive-age women at the SSA level is limited. Thus, this study aimed to estimate the pooled prevalence of anemia level and its determinants in SSA countries.

METHODS

We used a pooled data of 205,627 reproductive-age women from the recent demographic and health surveys of 29 SSA countries that were conducted between 2010-2021. A multilevel mixed-effects analysis with an ordered logistic regression model was fitted to identify determinants of anemia level and the deviance value was used to select the best-fitted model. First, bivariable ordinal logistic regression analysis was done and the proportional odds assumption was checked for each explanatory variable using a Brant test. Finally, in a multivariable multilevel ordinal logistic regression model, a p-value<0.05 and AOR with the corresponding 95% CI were used to identify determinants of anemia level. All analyses were done using Stata version 17 software.

RESULTS

The pooled prevalence of anemia among women of reproductive age in SSA was 40.5% [95% CI = 40.2%-40.7%], where 24.8% [95% CI: 24.6%-25.0%], 11.1% [95% CI = 10.9%-11.2%], and 0.8% [95% CI = 0.7%-0.8%] had mild, moderate, and severe anemia, respectively. The prevalence significantly varied from the lowest of 13% in Rwanda to the highest of 62% in Mali, and anemia was found as a severe public health problem (prevalence of ≥ 40%) in 18 countries. The regression result revealed that polygamous marriage, women and husband illiteracy, poor household wealth, shorter birth interval, non-attendance of antenatal care, underweight, unimproved toilet and water facilities, and low community-level women literacy were positively linked with high anemia level. Additionally, the likelihood of anemia was lower in women who were overweight and used modern contraception.

CONCLUSIONS

Overall results showed that anemia among women of reproductive age is a severe public health problem in SSA countries, affecting more than four in ten women. Thus, enhancing access to maternal health services (antenatal care and contraception) and improved sanitation facilities would supplement the existing interventions targeted to reduce anemia. Moreover, strengthening women's education and policies regulating the prohibition of polygamous marriage are important to address the operational constraints.

Prevalence and morbidity of urogenital schistosomiasis among pre-school age children in Cubal, Angola

BACKGROUND

Schistosomiasis is one of the most important neglected tropical diseases, with a great impact on public health and more than 200,000 deaths annually. Schistosoma haematobium causes urinary tract (UT) morbidity. Since schistosomiasis morbidity control programs focus on children older than 5 years, pre-school age children (PSAC) morbidity is not well known.

METHODS

We conducted a cross-sectional study in Cubal (Angola) among 245 PSAC with the objective of evaluating the prevalence of S. haematobium infection, the intensity of infection, and associated morbidity. For this purpose, urine filtration test followed by microscopic visualization and ultrasound examinations were performed.

RESULTS

The estimated overall prevalence of urogenital schistosomiasis was 30.2% (CI 95%; 24.5-35.9), with 20.3% (CI 95%; 15.3-25.3) of the samples analysed showing a high intensity of infection. A total of 54.5% (CI 95%; 47.6-61.8) of infected children presented UT lesions, showing a significant association between schistosomiasis infection and UT morbidity (p-value < 0.001). Bladder wall thickening was the most common lesion, being present in 100% of abnormal ultrasounds. We found that anaemia and severe malnutrition were not significantly associated with the development of UT lesions.

CONCLUSIONS

S. haematobium infection in PSAC causes great UT detectable morbidities. Therefore, there is an evident need of including them in mass drug administration (MDA) campaigns and consequently the development of an adapted praziquantel treatment dosage for children under 2 years of age.

Geospatial disparities and predictors of anaemia among pregnant women in Sub-Saharan Africa

BACKGROUND

Anaemia has become a major public health concern among women in Sub-Saharan Africa (SSA). However, little is known about the spatial disparities in anaemia prevalence and their associated factors among pregnant women in the region. This study analysed the spatial disparities in anaemia and their associated factors among pregnant women in rural and urban settings in SSA.

METHODS

This is a secondary analysis of the most recent demographic and health surveys of 26 countries in SSA. Spatial autocorrelation and hotspot assessment were conducted, while a multivariate logistic regression model was used to identify demographic factors associated with anaemia.

RESULTS

Anaemia was reported among ~50% of pregnant women in urban and rural areas of SSA. The hotspot analysis identified the West African sub-region as having a higher concentration of anaemia cases in rural settings. In urban areas, the odds of anaemia were significantly higher among pregnant women in their second trimester (Adjusted OR = 2.39, CI = 1.99, 2.76). On the other hand, pregnant women in their third trimester (Adjusted OR = 1.98, CI = 1.77, 2.22) and those who had taken intestinal parasite drugs (Adjusted OR = 1.12 CI = 1.02, 1.23) had a higher likelihood of having anaemia in rural areas. Pregnant women aged 35-39 years (Adjusted OR = 0.52, CI = 0.33, 0.81) and those aged 40-44 years (Adjusted OR = 0.69, CI = 0.50, 0.95) had a lesser likelihood of having anaemia compared to women aged 15-19 years in urban and rural areas respectively. Compared to Congo DR, Benin (OR = 2.22, CI = 1.51, 3.28) and Mali (OR = 3.71, CI = 2.73, 5.05) had higher odds of anaemia in urban and rural areas respectively.

CONCLUSIONS

Spatial disparities in anaemia persist among pregnant women in rural and urban settings in SSA. Prevailing spatial variations in anaemia may be addressed by specialised interventions considering the contextual residential settings and socio-economic factors highlighted in this study.

The effect of iron supplementation on maternal iron deficiency anemia does not differ by baseline anemia type among Tanzanian pregnant women without severe iron deficiency anemia

PURPOSE

Whether anemia type modifies the risk of pregnancy and newborn outcomes and the effectiveness of iron supplementation is unclear. We examined the association of iron deficiency anemia (IDA) and non-iron deficiency anemia (NIDA) on the risks of these outcomes and the extent to which anemia type modifies the impact of prenatal iron supplementation.

METHODS

This was a secondary analysis of a placebo-controlled trial of iron supplementation among 1450 HIV-negative women in Tanzania. Eligibility criteria included gestational age < 27 weeks, hemoglobin > 85 g/L, and ferritin > 12 µg/L. Individuals were categorized as non-anemia, IDA or NIDA using hemoglobin, ferritin and CRP. Analyses were conducted using regression models and likelihood ratio tests.

RESULTS

Compared to the non-anemia group, delivery hemoglobin was lower by 15 g/L (95% CI 10.9, 19.3) in the baseline IDA group, and 7.3 g/L (95% CI 3.1, 11.5) in the baseline NIDA group. The RRs of anemia severity, iron deficiency, placental malaria, stillbirths, perinatal mortality, birthweight, and preterm birth were not different among women in the baseline NIDA group (vs. non-anemia) compared to the baseline IDA group (vs. non-anemia). The difference in the mean delivery hemoglobin for iron supplementation and placebo arms was 8 g/L (95% CI 6, 11) in the non-anemia group, 7 g/L (95% CI 2, 13) in the NIDA group, and 16 g/L (95% CI 10, 22) in the IDA group.

CONCLUSION

Iron supplementation is effective even among pregnant women with NIDA.

TRIAL REGISTRATION

NCT01119612 (May 7, 2010).

Bayesian spatio-temporal modelling and mapping of malaria and anaemia among children between 0 and 59 months in Nigeria

BACKGROUND/M&M

A vital aspect of disease management and policy making lies in the understanding of the universal distribution of diseases. Nevertheless, due to differences all-over host groups and space-time outbreak activities, data are subject to intricacies. Herein, Bayesian spatio-temporal models were proposed to model and map malaria and anaemia risk ratio in space and time as well as to ascertain risk factors related to these diseases and the most endemic states in Nigeria. Parameter estimation was performed by employing the R-integrated nested Laplace approximation (INLA) package and Deviance Information Criteria were applied to select the best model.

RESULTS

In malaria, model 7 which basically suggests that previous trend of an event cannot account for future trend i.e., Interaction with one random time effect (random walk) has the least deviance. On the other hand, model 6 assumes that previous event can be used to predict future event i.e., (Interaction with one random time effect (ar1)) gave the least deviance in anaemia.

DISCUSSION

For malaria and anaemia, models 7 and 6 were selected to model and map these diseases in Nigeria, because these models have the capacity to receive strength from adjacent states, in a manner that neighbouring states have the same risk. Changes in risk and clustering with a high record of these diseases among states in Nigeria was observed. However, despite these changes, the total risk of malaria and anaemia for 2010 and 2015 was unaffected.

CONCLUSION

Notwithstanding the methods applied, this study will be valuable to the advancement of a spatio-temporal approach for analyzing malaria and anaemia risk in Nigeria.

Effect of Schooling on Anemia and Nutritional Status Among Women: A Natural Experiment in Ethiopia

This study estimates the effect of length of schooling on anemia and nutritional status and evaluates the cost-effectiveness of primary schooling as an anemia intervention for women of childbearing age in Ethiopia. In 1994-1995, Ethiopia abolished primary school tuition fees and embarked on a large-scale educational investment program, which increased primary school enrollment and retention. An instrumented regression-discontinuity design was used to examine the effect on anemia risk and body mass index (BMI) of an increase in length of schooling resulting from the reforms, as a natural experiment. Anemia and BMI biomarkers and demographic data for 13,984 women were obtained from the 2011 and 2016 Ethiopia Demographic and Health Surveys, with the 2019 Mini Demographic and Health Survey used for robustness checks. Results indicate that each additional year of schooling reduced anemia risk by 3 percentage points (9.2%-11.2% reduction) and increased BMI (weight (kg)/height (m)2) by 0.26-0.42. Primary education was cost-effective-based on World Health Organization cost-effectiveness thresholds-as an anemia intervention, with a cost per anemia case averted of US$1,654. The findings suggest that investment in education reduces anemia risk later in life.

Intravenous versus oral iron for iron deficiency anaemia in pregnant Nigerian women (IVON): study protocol for a randomised hybrid effectiveness-implementation trial

Background

Anaemia in pregnancy is highly prevalent in African countries. High-dose oral iron is the current recommended treatment for pregnancy-related iron deficiency anaemia (IDA) in Nigeria and other African countries. This oral regimen is often poorly tolerated and has several side effects. Parenteral iron preparations are now available for the treatment of IDA in pregnancy but not widely used in Africa.

The IVON trial is investigating the comparative effectiveness and safety of intravenous ferric carboxymaltose versus oral ferrous sulphate standard-of-care for pregnancy-related IDA in Nigeria. We will also measure the implementation outcomes of acceptability, feasibility, fidelity, and cost-effectiveness for intravenous ferric carboxymaltose.

Methods

This is an open-label randomised controlled trial with a hybrid type 1 effectiveness-implementation design, conducted at 10 health facilities in Kano (Northern) and Lagos (Southern) states in Nigeria. A total of 1056 pregnant women at 20–32 weeks’ gestational age with moderate or severe anaemia (Hb < 10g/dl) will be randomised 1:1 into two groups. The interventional treatment is one 1000-mg dose of intravenous ferric carboxymaltose at enrolment; the control treatment is thrice daily oral ferrous sulphate (195 mg elemental iron daily), from enrolment till 6 weeks postpartum.

Primary outcome measures are (1) the prevalence of maternal anaemia at 36 weeks and (2) infant preterm birth (<37 weeks’ gestation) and will be analysed by intention-to-treat. Maternal full blood count and iron panel will be assayed at 4 weeks post-enrolment, 36 weeks’ gestation, delivery, and 6 weeks postpartum. Implementation outcomes of acceptability, feasibility, fidelity, and cost will be assessed with structured questionnaires, key informant interviews, and focus group discussions.

Discussion

The IVON trial could provide both effectiveness and implementation evidence to guide policy for integration and uptake of intravenous iron for treating anaemia in pregnancy in Nigeria and similar resource-limited, high-burden settings. If found effective, further studies exploring different intravenous iron doses are planned.

Trial registration

ISRCTN registry ISRCTN63484804. Registered on 10 December 2020

Clinicaltrials.govNCT04976179. Registered on 26 July 2021

The current protocol version is version 2.1 (080/080/2021).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06690-2.

Spatial distributions and determinants of anaemia among adolescent girls in Ethiopia: a secondary analysis of EDHS 2016 - a cross-sectional study

OBJECTIVE

This study aimed to investigate the spatial distributions and determinants of anaemia among adolescent girls in Ethiopia. Exploring the spatial epidemiology of anaemia and identifying the risk factors would inform policymakers to come up with evidence-based prevention strategies for anaemia, especially in adolescent girls, who are the most affected segment of the population.

METHODS

Secondary analysis of the Ethiopian Demographic and Health Survey 2016 was conducted. A total of 3172 adolescents were included in the analysis. The Bernoulli model was fitted using SaTScan V.9.6 to identify hotspot areas and the geospatial pattern and prediction of anaemia were mapped using ArcGIS V.10.8. A multilevel logistic regression model was fitted to identify factors associated with anaemia among adolescent girls. Adjusted OR with 95% CI was calculated and variables having a p value less than 0.05 were statistically significant factors of anaemia.

RESULT

The overall prevalence of anaemia among adolescent girls in Ethiopia was 23.8 (22.4 to 25.3), with significant spatial variations across the country. The SaTScan analysis identified a primary cluster in the eastern, northeastern and southeastern parts of Ethiopia (loglikelihood ratio=39, p<0.001). High anaemia prevalence was observed in eastern parts of the country. In the multivariable multilevel logistic regression analysis, no formal education (adjusted OR (AOR)=1.49, 95% CI 1.05 to 2.12), Afar (AOR=3.36, 95% CI 1.87 to 6.05), Somali (AOR=4.63, 95% CI 2.61 to 8.23), Harari (AOR=1.90, 95% CI 1.32 to 4.10), Dire Dawa (AOR=2.32, 95% CI 1.32 to 4.10) and high cluster altitude (AOR=1.37, 95% CI 1.03 to 1.82) were significantly associated with anaemia.

CONCLUSION

The national distributions of anaemia varied substantially across Ethiopia. Educational status, region and cluster altitude were significantly associated with anaemia in the multivariable logistic regression model. Thus, targeted public health interventions for adolescent girls should be implemented in the hotspot areas.

Prevalence and factors associated with anaemia among pregnant women attending reproductive and child health clinics in Mbeya region, Tanzania

Anaemia is a global public health issue, disproportionately affecting vulnerable populations such as pregnant women. The aim of this study was to assess the prevalence of anaemia and to identify factors associated with the condition among pregnant women attending antenatal clinics in the Mbeya Region of Tanzania. A cross sectional study was conducted with 420 pregnant women (<28 weeks of gestation) attending antenatal visits in the 7 districts of the Mbeya Region. A structured questionnaire was used to collect demographic information and eating habits using a 24hours dietary recall. A blood sample was collected and tested for hemoglobin content using the HemoCue 201+. Multivariate analysis was performed using standard logistic regression to explore the association between anaemia status with socio-demographic, reproductive and nutritional factors. Overall prevalence of anaemia in pregnant women was 25.5%. Out of 107 pregnant women diagnosed with anaemia and, sixty six had mild anaemia. In a multivariate logistical regression analysis anaemic women was associated with pregnant women coming from lower socio-economic status [adjusted OR = 2.40, 95%CI (1.05, 5.48)]. Moreover, anaemia was less associated with pregnant women who were living in Mbeya district council [adjusted OR = 0.28, 95%CI (0.11, 0.72)], consume at least once a day dark green leafy vegetables [adjusted OR = 0.53, 95% CI (0.30, 0.94)], and vegetable liquid cooking oil [adjusted OR = 0.56, 95% CI (0.34, 0.98)]. The prevalence of anaemia among the pregnant women falls in the category of moderate public health problem according to the WHO classification. Low socio-economic status, consumption of green leafy vegetables and vegetable liquid cooking oil were significantly and independently associated with anaemia during pregnancy. Thus, special attention should be given to pregnant women who are in lower socio-economic status and those not consuming vegetables. Interventions that integrate health and nutrition education in reproductive and child health clinics are needed to combat anaemia.

Prenatal anemia and postpartum hemorrhage risk: A systematic review and meta-analysis

INTRODUCTION

Postpartum hemorrhage (PPH) has remained the leading cause of maternal mortality. While anemia is a leading contributor to maternal morbidity, molecular, cellular and anemia-induced hypoxia, clinical studies of the relationship between prenatal-anemia and PPH have reported conflicting results. Therefore, our objective was to investigate the outcomes of studies on the relationships between prenatal anemia and PPH-related mortality.

MATERIALS AND METHODS

Electronic databases (MEDLINE, Scopus, ClinicalTrials.gov, PROSPERO, EMBASE, and the Cochrane Central Register of Controlled Trials) were searched for studies published before August 2019. Keywords included "anemia," "hemoglobin," "postpartum hemorrhage," and "postpartum bleeding." Only studies involving the association between anemia and PPH were included in the meta-analysis. Our primary analysis used random effects models to synthesize odds-ratios (ORs) extracted from the studies. Heterogeneity was formally assessed with the Higgins' I² statistics, and explored using meta-regression and subgroup analysis.

RESULTS

We found 13 eligible studies investigating the relationship between prenatal anemia and PPH. Our findings suggest that severe prenatal anemia increases PPH risk (OR = 3.54; 95% CI: 1.20, 10.4, p-value = 0.020). There was no statistical association with mild (OR = 0.60; 95% CI: 0.31, 1.17, p-value = 0.130), or moderate anemia (OR = 2.09; 95% CI: 0.40, 11.1, p-value = 0.390) and the risk of PPH.

CONCLUSION

Severe prenatal anemia is an important predictive factor of adverse outcomes, warranting intensive management during pregnancy. PROSPERO Registration Number: CRD42020149184; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=149184.