I've never worked in that area myself but friends have....
basically it could be a mixed bag of outpatients (pregnant women and new mums with back pain,SIJ pain etc), maternity unit- going around the ward giving mums advice on abdominal and pelvic floor exercises, antenatal- advice and education on posture, lifting, exercises to protect the back...more abdominal exercises etc!! I guess you may also come across women with continence problems and will probably have to advise on exercises etc....I guess its a more musculoskeletal type of placement
Hope that helps!