In this case report a 37-year-old women, 38 weeks and four days pregnant, presented with an occult hip fracture. Before surgery, it was important to investigate the nature of the fracture as the treatment differed accordingly. The patient was investigated with MRI and following acute caesarean section a PET-CT scan was performed with no proof of malignancy. An undetectable low level of vitamin D and the pathology report determined the cause of the fracture to be transient osteoporosis of pregnancy. The patient received a total hip arthroplasty and was referred to further treatment at a department of endocrinology.