Aweke Mekuriaw Nibret, Fentie Elsa Awoke, Agimas Muluken Chanie, Baffa Lemlem Daniel, Shewarega Ever Siyoum, Belew Aysheshim Kassahun, Muhammad Esmael Ali, Mengistu Berhanu
Department of Human Nutrition, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.
Department of Reproductive Health, Institute of Public Health, College of Medicine and Health Science, University of Gondar, Gondar, Ethiopia.
PLoS One. 2025 Jan 31;20(1):e0318422. doi: 10.1371/journal.pone.0318422. eCollection 2025.
Neural tube defects (NTDs) are serious congenital anomalies of the central nervous system caused by disruptions in early embryonic development. The prevalence is about twice as common in low- and middle-income countries and more prevalent in sub-Saharan Africa. Folic acid deficiency is a major risk factor and common during pregnancy. However, limited research on preconception folic acid supplementation in this region highlights the need for systematic reviews and targeted interventions to improve maternal and fetal health.
We conducted a systematic literature search in EMBASE, MEDLINE, Scopus, CINAHL, Google Scholar, and Google for studies on the proportion of folic acid supplementation during the preconception period, covering publications up to January 2024. Study quality was assessed using the Newcastle-Ottawa Scale. Heterogeneity was evaluated with Cochrane Q and I2 statistics, and small study effects were tested with Egger's test at a 5% significance level. The certainty of evidence was assessed using the GRADE approach. A random-effects model was used to estimate the pooled proportion of FA supplementation during the preconception period in sub-Saharan African countries.
This systematic review included 28 studies with a total of 12,562 participants. The highest (45.2%) and lowest (1.9%) proportion of folic acid supplementation during preconception period were recorded in the southern and Amhara regions of Ethiopia, respectively. The estimated pooled proportion of folic acid supplementation among women in Sub-Saharan Africa (SSA) during preconception period was (14.10%; 95% CI: 11.22-16.98) with significant heterogeneity between studies (I2 = 97.71%, p = 0.001). In sub-group analysis based on corresponding countries the highest estimated folic acid supplementation proportion during preconception period was found in studies conducted in Kenya ((22%; 95% CI: 19%-25%), I2 = 97.7%), followed by studies conducted in Ghana (20%; 95% CI: 7%-33%), I2 = 96.9%). The majority of the studies included in the analysis are of high quality, with quality scores ranging from 7 to 8. The certainty of evidence was assessed using the GRADE approach, resulting in a low overall rating.
The results of this systematic review and meta-analysis indicated that folic acid supplementation during preconception period is significantly low among mothers in sub-Saharan African countries, despite being one of the best approaches to improve birth outcomes. Therefore, healthcare organizations, governments, policymakers, and other stakeholders involved in folic acid supplementation must collaborate on developing strategies to improve its uptake during the preconception period.
神经管缺陷（NTDs）是由早期胚胎发育中断引起的严重中枢神经系统先天性异常。在低收入和中等收入国家，其患病率约为其他国家的两倍，在撒哈拉以南非洲地区更为普遍。叶酸缺乏是一个主要风险因素，在孕期很常见。然而，该地区关于孕前补充叶酸的研究有限，这凸显了进行系统评价和针对性干预以改善母婴健康的必要性。
我们在EMBASE、MEDLINE、Scopus、CINAHL、谷歌学术和谷歌上进行了系统的文献检索，以查找关于孕前叶酸补充比例的研究，涵盖截至2024年1月的出版物。使用纽卡斯尔-渥太华量表评估研究质量。用Cochrane Q和I²统计量评估异质性，并在5%显著性水平下用Egger检验检验小研究效应。使用GRADE方法评估证据的确定性。采用随机效应模型估计撒哈拉以南非洲国家孕前叶酸补充的合并比例。
本系统评价纳入了28项研究，共12562名参与者。埃塞俄比亚南部和阿姆哈拉地区孕前叶酸补充比例分别为最高（45.2%）和最低（1.9%）。撒哈拉以南非洲（SSA）地区女性孕前叶酸补充的估计合并比例为（14.10%；95%CI：11.22 - 16.98），研究间存在显著异质性（I² = 97.71%，p = 0.001）。在基于相应国家的亚组分析中，孕前叶酸补充比例估计最高的是在肯尼亚进行的研究（（22%；95%CI：19% - 25%），I² = 97.7%），其次是在加纳进行的研究（20%；95%CI：7% - 33%），I² = 96.9%）。分析中纳入的大多数研究质量较高，质量得分在7到8分之间。使用GRADE方法评估证据的确定性，总体评级较低。
本系统评价和荟萃分析的结果表明，尽管孕前补充叶酸是改善出生结局的最佳方法之一，但撒哈拉以南非洲国家母亲的孕前叶酸补充率显著较低。因此，参与叶酸补充的医疗保健组织、政府、政策制定者和其他利益相关者必须合作制定策略，以提高孕前叶酸的摄入量。
