Effects of a preconception lifestyle intervention in obese infertile women on diet and physical activity; A secondary analysis of a randomized controlled trial

BackgroundLifestyle changes are notoriously difficult. Since women who intend to become pregnant are more susceptible to lifestyle advice, interventions during this time window might be more effective than interventions during any other period in life. We here report the effects of the first large preconception lifestyle intervention RCT on diet and physical activity in obese infertile women.MethodsIn total, 577 women were randomized between a six-month lifestyle intervention program (intervention group; N = 290) or prompt infertility treatment (control group; N = 287). Self-reported dietary behaviors and physical activity were assessed at baseline, three, six and twelve months after randomization. Mixed models were used to analyze differences between groups.ResultsCompared to the control group, the intervention group reduced their intake of sugary drinks at three months (-0.5 glasses/day [95% C.I. = -0.9;-0.2]), of savory snacks at three (-2.4 handful/week [-3.4;-1.4]) and at six months (-1.4 handful/week [-2.6;-0.2]), and of sweet snacks at three (-2.2 portion/week [-3.3;-1.0]) and twelve months after randomization (-1.9 portion/week [-3.5;-0.4]). Also, the intervention group was more moderate to vigorous physically active at three months after randomization compared to the control group (169.0 minutes/week [6.0; 332.1]).ConclusionOur study showed that obese infertile women who followed a six-month preconception lifestyle intervention program decreased their intake of high caloric snacks and beverages, and increased their physical activity. These changes in lifestyle may not only improve women’s health but their offspring’s health too.

背景：众所周知，生活方式的改变极具挑战性。由于计划妊娠的女性更易接受生活方式相关建议，因此此阶段的干预措施或许比人生其他任何时期的干预都更为有效。本研究首次针对肥胖不孕女性开展大型孕前生活方式干预随机对照试验（Randomized Controlled Trial, RCT），报告其对饮食与身体活动的干预效果。
方法：总计577名女性被随机分配至为期6个月的生活方式干预组（干预组，N=290）或即刻不孕治疗对照组（对照组，N=287）。研究人员在随机分组时、分组后3、6及12个月评估受试者自我报告的饮食行为与身体活动水平，并采用混合效应模型分析两组间的差异。
结果：与对照组相比，干预组在随机分组后3个月时的含糖饮料摄入量有所减少（-0.5杯/天，95%置信区间：-0.9~-0.2）；3个月时的咸味零食摄入量（-2.4份/周，95%置信区间：-3.4~-1.4）及6个月时的咸味零食摄入量（-1.4份/周，95%置信区间：-2.6~-0.2）均有所减少；同时在3个月时的甜味零食摄入量（-2.2份/周，95%置信区间：-3.3~-1.0）及12个月时的甜味零食摄入量（-1.9份/周，95%置信区间：-3.5~-0.4）亦有所减少。此外，相较于对照组，干预组在随机分组后3个月的中等至高强度身体活动时长更高（169.0分钟/周，95%置信区间：6.0~332.1）。
结论：本研究表明，参与为期6个月孕前生活方式干预的肥胖不孕女性，其高热量零食与饮料的摄入量有所减少，身体活动水平有所提升。此类生活方式的改变不仅可改善女性自身健康状况，亦可能对其后代的健康产生积极影响。