Sleep impairment during pregnancy can impact quality of life and lead to excessive gestational weight gain, gestational diabetes mellitus, postpartum depression, and delivery complications. In non-pregnant adults, exercise improves sleep quality, duration and onset latency. PURPOSE: To determine if exercise performed during pregnancy improves sleep outcomes. METHODS: A systematic review was conducted through February 2021 using online databases and hand searching. Randomized control trials available in English were eligible if the sample included pregnant woman, the intervention included any mode of exercise, the intervention group was compared to a standard care group, and sleep was included as an outcome measure (prevalence or severity of sleep quality, disturbances, and/or insomnia). Mean differences and standardized mean differences were calculated to compare sleep outcomes across studies. Heterogeneity of results was calculated using I2. RESULTS: 2122 articles were found using the search terms, 8 studies met inclusion criteria (n = 540). ‘Low’ quality evidence determined that prenatal exercise reduced the amount of self-reported sleep disturbances (2 RCT’s n = 115; IV -0.53, 95% CI -0.90, -0.16, Z = 2.79 p = 0.005) during pregnancy. ‘Very low’ to ‘low’ quality evidence supported exercise for improving sleep quality (3 RCT’s n = 316; IV -3.21, 95% CI -3.82, -2.60). Other sleep outcomes were not able to be analyzed due to variability of measurement and an insufficient number of studies with the same outcome measure. CONCLUSION: Compared with not exercising, exercise during pregnancy decreased reported sleep disturbances and was protective against the natural decline in subjective sleep quality during pregnancy. Although insomnia severity was found to decrease following exercise, there was a lack of sufficient research to support to state this claim. Due to the low quality of studies, variety of interventions, and differences in outcome measures reported, more research in this area is warranted.