Purpose/Hypothesis: This study sought to investigate lateral abdominal muscle performance, pain, disability and functional status in women early after childbirth (2-8 weeks after delivery). A better understanding of abdominal muscle morphology and function may assist with the development of an effective early intervention program for the rehabilitation of the abdominal muscles in this patient population. Number of Subjects: 30 women between the ages of 18-45. Materials/Methods: Baseline information was gathered including age, body mass index (BMI), number of pregnancies, date of delivery, history of low back pain (LBP), weight gain during pregnancy, activity level and pain rating. Functional status information was gathered using the modified Oswestry Disability Index. A physical examination was performed on all subjects. Abdominal muscle performance was assessed using rehabilitative ultrasound imaging (RUSI) during the subjects performing the abdominal hollowing exercise (AHE). Muscle thickness measurements of the transversus abdominis (TrA), internal oblique (IO) and external oblique (EO) were taken from all subjects. Results: The proportion of subjects who demonstrated the ability to correctly perform the AHE was 5 of the 30 (16.7%) with a mean percent thickness change of the TrA at rest compared to activation of 99.6, SD (25.4) (group 1), compared to 62.4, SD (38.9) for the 25 subjects who were not able to correctly perform the AHE (group 2). The average ODI scores were 1.6, SD (2.6) for group 1 and 2.6, SD (4.0) for group 2. The average BMI of the women in group 1 was 24, SD (4.6), compared to 25, SD (3.0) for group 2. The average number of pregnancies was 2 for both groups. Zero women in group 1 reported a history of LBP prior to pregnancy, compared to 4 in group 2. The average days from delivery at the time of participation in the study was 39, SD (14.9) in group 1, compared to 34, SD (12.2) in group 2. Weight gain averages were 11 kg, SD (3.5) for group 1 and 13.2 kg, SD (4.5) for group 2. The average minutes/week of moderate exercise reported by group 1 was 61, SD (41.6) compared to 121, SD (88.3) for group 2. All subjects in both groups had current pain ratings of <2. Conclusions: The majority of the women in the study were not able to correctly activate the TrA during the AHE despite having no or a low level of pregnancy related low back pain (LBP). A program which teaches women the AHE early after childbirth may be beneficial in improving motor control deficits in this patient population regardless of pain level. Further research is needed comparing women with and without pregnancy related LBP. Clinical Relevance: To the authors knowledge this is the first study to show a decreased muscle performance of the lateral abdominal muscles in women early after childbirth. Improving the muscle performance of the TrA early after childbirth may be beneficial in improving spine stability and avoidance of injuries. This information would be useful for physical therapists in designing both prenatal and postnatal rehabilitation programs.