Background. Iron deficiency anemia is a common health problem that affects children under the age of five. Children’s cognitive performance is impaired by iron deficiency, which impacts their psychomotor development. Therefore, the aim of this study was to determine the global prevalence and associated factors of iron deficiency and iron deficiency anemia among under-5 children. Methods. Relevant publications published till March 30, 2021 were identified in databases such as Medline/PubMed, Science Direct, Popline, EMBASE, African Journals Online, Scopus, and Google Scholar. The STATA version 11 software was utilized for the analysis. To determine the level of heterogeneity, I2 test statistics were used. To detect publication bias, funnel plots analysis and the Egger weighted regression test were used. Results. The global pooled prevalence of iron deficiency anemia and iron deficiency was 16.42% (95% CI: 10.82, 22.01) and 17.95% (95% CI: 13.49, 22.41), respectively. Age less than 2 years (OR = 1.26; 95% CI: 1.14, 1.38) and living in a large family size (OR = 1.38; 95% CI: 1.18, 1.58) were associated with iron deficiency anemia. Children born from anemic mother, low birth weight, and do not drink iron fortified milk (OR = 1.20; 95% CI: 1.05, 1.36), (OR = 1.15; 95% CI: 1.01, 1.36) and (OR = 1.28; 95% CI: 1.10, 1.46), respectively were associated factors of iron deficiency in under-5 children. Conclusion. The prevalence of iron deficiency anemia and iron deficiency was significant across the globe, particularly in Asia and Africa. Therefore, regular screening and treatment of iron deficiency and iron deficiency anemia are required especially in high-risk children to reduce their complication. PROSPERO registration number: CRD42021267060

Background More than one-third of reproductive aged women in Ethiopia use hormonal contraceptives to prevent conception. The present study aimed to compare the hematological parameters of reproductive-age women taking hormonal contraceptives at the University of Gondar Comprehensive Specialized Referral Hospital, Northwest Ethiopia in 2021. Methods A comparative cross-sectional study was conducted from April to June 2021. A total of 240 study participants were recruited by using a consecutive sampling technique. Data on socio-demographic variables and clinical data were collected through face-to-face interviews using a structured questionnaire and medical record reviews, respectively. Three milliliter venous blood was collected for complete blood count analysis using Unicel DxH 800 coulter hematology analyzer. Data was entered into Epi-data 4.4.3.1 version then exported to IBM SPSS v25 for analysis. Kruskal-Wallis H, Dunn-Bonferroni pairwise comparison test, and Spearman’s correlation analysis were used for inferential statistics. P<0.05 were considered statistically significant. Result The median and interquartile range of platelet count among combined oral contraceptive users was 285(238–332) which is significantly higher than that of depot medroxyprogesterone acetate users 246(220–226) (p = 0.010), implant user 247(221–297) (p = 0.034), and controls 256(224–278) (p = 0.015). The result also showed long-term use of implant negatively correlated with red blood cell count (p = 0.033). Conclusion This finding concludes that combined oral contraceptive users had a higher platelet counts than controls while long-term use of implants can result in low red blood cells count. Therefore, a baseline evaluation of complete blood count in women desiring contraceptive methods would also be recommended.