McGrice Melanie, Porter Judi
Dietetics Department, Eastern Health, 5 Arnold Street, Box Hill VIC 3128, Australia.
Nutrition Plus Enterprises, 1004/1 Queens Road, Melbourne VIC 3004, Australia.
Nutrients. 2017 Feb 27;9(3):204. doi: 10.3390/nu9030204.
(1) Background: Medical interventions including assisted reproductive technologies have improved fertility outcomes for many sub-fertile couples. Increasing research interest has investigated the effect of low carbohydrate diets, with or without energy restriction. We aimed to systematically review the published literature to determine the extent to which low carbohydrate diets can affect fertility outcomes; (2) Methods: The review protocol was registered prospectively with Prospective Register for Systematic Reviews (registration number CRD42016042669) and followed Preferred Reporting Items For Systematic Reviews and Meta-Analyses guidelines. Infertile women were the population of interest, the intervention was low carbohydrate diets (less than 45% total energy from carbohydrates), compared to usual diet (with or without co-treatments). Four databases were searched from date of commencement until April 2016; a supplementary Google scholar search was also undertaken. Title and abstract, then full text review, were undertaken independently and in duplicate. Reference lists of included studies and relevant systematic reviews were checked to ensure that all relevant studies were identified for inclusion. Quality assessment was undertaken independently by both authors using the Quality Criteria Checklist for Primary Research. Outcome measures were improved fertility outcomes defined by an improvement in reproductive hormones, ovulation rates and/or pregnancy rates; (3) Results: Seven studies fulfilled the inclusion criteria and were included in the evidence synthesis. Interventions were diverse and included a combination of low carbohydrate diets with energy deficit or other co-treatments. Study quality was rated as positive for six studies, suggesting a low risk of bias, with one study rated as neutral. Of the six studies which reported changes in reproductive hormones, five reported significant improvements post intervention; (4) Conclusion: The findings of these studies suggest that low carbohydrate diets warrant further research to determine their effect. These randomised controlled trials should consider the effect of carbohydrates (with or without energy deficit) on hormonal and fertility outcomes.
（1）背景：包括辅助生殖技术在内的医学干预措施改善了许多不孕夫妇的生育结局。越来越多的研究关注了低碳水化合物饮食（无论是否限制能量摄入）的影响。我们旨在系统回顾已发表的文献，以确定低碳水化合物饮食对生育结局的影响程度；（2）方法：该综述方案已前瞻性地在系统评价前瞻性注册库（注册号CRD42016042669）注册，并遵循系统评价和Meta分析的首选报告项目指南。研究对象为不孕女性，干预措施为低碳水化合物饮食（碳水化合物提供的总能量低于45%），并与常规饮食（无论是否联合其他治疗）进行比较。从开始日期至2016年4月检索了四个数据库；还进行了补充的谷歌学术搜索。先独立且重复地进行标题和摘要审查，然后进行全文审查。检查纳入研究的参考文献列表和相关的系统评价，以确保识别出所有相关研究纳入。两位作者均独立使用原发性研究质量标准清单进行质量评估。结局指标为生育结局改善，定义为生殖激素、排卵率和/或妊娠率的改善；（3）结果：七项研究符合纳入标准并纳入证据综合分析。干预措施多种多样，包括低碳水化合物饮食与能量不足或其他联合治疗的组合。六项研究的质量评级为阳性，表明偏倚风险较低，一项研究评级为中性。在六项报告生殖激素变化的研究中，五项报告干预后有显著改善；（4）结论：这些研究结果表明，低碳水化合物饮食值得进一步研究以确定其效果。这些随机对照试验应考虑碳水化合物（无论是否存在能量不足）对激素和生育结局的影响。
