Background: Pregnancy generates a strong stress response in women, which makes the burden on their lower backs heavier and increases their sensation of fatigue. Aim: The current study aims to evaluate the effectiveness of birth ball abdominal core training on fatigue and low back pain among primigravida. Subjects and Method: Non randomized a quasi-experimental research design was used to conduct the current study at the New Obstetric and Gynecologic Hospital in Mansoura, Egypt. 100 third-trimester pregnant women were divided into control and study groups. Three tools were used for data collection: tool I: structured interview for basic and clinical data. Tool II: Visual Analogue Scale for pain measurement and Tool III: Fatigue Assessment Scale for evaluating fatigue level. Results: At the beginning of the study, pain scores for low back pain were similar between the two groups. After the intervention, the study group showed a significant reduction in low back pain at the first, second, and third followups compared to the control group (first follow-up: p = 0.001; second follow-up: p = 0.001; third follow-up: p = 0.001). Additionally, there was no significant difference in fatigue levels between both groups before the intervention, but the study group had a significantly lower fatigue level after intervention compared to the control group (before intervention: p = 0.181; after intervention: p = 0.001). Conclusion: Birth ball abdominal core training is an effective intervention for managing pregnancy-related fatigue and low back pain. Recommendations: Birth ball abdominal core training should be utilized by maternity nurses as a part of routine antenatal care.