You can actually get a copy of all written comments from attending and residents from Julie Andrews, the secretary for the clerkship. You will never forget this experience. Simple but good treatment of all the important topics. Also, over 2000 questions, including multiple choice and clinical scenarios. I only wish there was a book like this for each clerkship.
Standard boards review outline format.
Fairly extensive coverage of all the important Ob-Gyn topics. Good chapters on practical anatomy and surgical approaches. You could conceivably use this as your sole source of study for the rotation. First, some of the topics are covered in way, way too much detail. The good part about this is that if you actually do these questions, you'll definitely be prepared.