Midwife-led guidance on daily steps and physical activity to improve sleep quality in the third trimester of pregnancy: An examination of its rationale

• Midwife-guided activity improved sleep quality in late pregnancy. • Maintaining 7195 steps/day enhanced multiple sleep parameters. • Higher activity (7.2 metabolic equivalents/h/day) predicted better sleep quality. • Fewer daily steps were linked to poorer sleep in regression analysis. • Propensity score analysis confirmed the step–sleep quality association. Sleep during pregnancy is crucial for maternal and neonatal health, including delivery and neonatal outcomes. Sleep quality typically declines most markedly in the third trimester, highlighting the need for early interventions to maintain adequate sleep. Moderate-intensity aerobic physical activity is associated with improved sleep quality in pregnant women; however, evidence on the specific amount and intensity of exercise that improves sleep quality in pregnant women is lacking. In this study, we aimed to elucidate the relationships of sleep quality with daily step count and physical activity levels (metabolic equivalents METs) in women in the third trimester of pregnancy. This longitudinal observational study included 70 third-trimester pregnant women who had not been instructed to restrict daily activities. Sleep was assessed using the Japanese version of the Pittsburgh Sleep Quality Index, and physical activity was continuously monitored using waist-worn accelerometers over 4 weeks. Statistical analyses included descriptive statistics, logistic regression, and matching propensity scores. Data were analysed using IBM SPSS, with a significance threshold set at P < 0.05. Participants who maintained an average of 7,195 steps/day, 7.2 METs/hour/day, and high physical activity levels demonstrated better outcomes across multiple sleep indicators. Logistic regression and propensity score analyses demonstrated that a decrease in daily step count was a predictor of poorer sleep quality. These findings are consistent with recommendations encouraging routine walking among pregnant women in Japan and offer reference target values for physical activity guidance, which may be considered in midwifery counselling and prenatal care recommendations.