Final answer:
The Semi-Fowler's position is recommended for patients with Pelvic Inflammatory Disease (PID) to help alleviate pain and promote drainage from the pelvic area.
Step-by-step explanation:
The most suitable position for a patient with Pelvic Inflammatory Disease (PID) when in bed is the Semi-Fowler's position. This position involves the patient being semi-upright at an angle of about 30 to 45 degrees. It helps to promote drainage and reduce pressure from the abdomen, which can help alleviate pain associated with PID. In contrast, a supine position might not provide the same comfort due to the pressure it can place on the pelvic area, while a prone position might not be as effective for drainage. The side-lying position with legs flexed may offer comfort but does not aid in drainage as well as the Semi-Fowler's position.