BACKGROUND: Pregnancy can alter the rectus abdominis, which abdominoplasty can potentially correct. OBJECTIVES: This study aims to examine these muscle changes during pregnancy and evaluate how effectively abdominoplasty with double folds of the rectus abdominis tightens the muscle. METHODS: We collected clinical data from nulliparous and pregnant patients who had abdominoplasty with double folds of the rectus abdominis. We measured the linea alba width, rectus abdominis width and thickness, its cross-sectional area, and abdominal circumference. Postoperative complications were also recorded. The assessment of satisfaction with the morphology of the rectus abdominis, both pre- and post-surgery, was conducted using a 5-point Likert scale. RESULTS: The study included 400 women: 171 nulliparous, 106 with one pregnancy (group 1), and 123 with two or more pregnancies (group 2). Complete postoperative data were available for 32 patients (group 3). Significant widening of the linea alba was found in group 1 and group 2. The rectus abdominis width increased significantly in group 1 but not in group 2. Its thickness remained unchanged in group 1 but decreased in group 2, mirroring the pattern of its cross-sectional area. In group 3, both the linea alba and rectus abdominis width decreased, while thickness and cross-sectional area increased. Post-surgery satisfaction with muscle morphology improved significantly, with no serious complications reported. CONCLUSIONS: Pregnancy can cause the rectus abdominis muscle to separate, widening the linea alba and flattening the muscle. Abdominoplasty, which reinforces the muscle with double folds, effectively resolves this, resulting in high patient satisfaction and few complications.