The book is called: Exercising Through Your Preganancy by James F. Clapp III. M.D.

Here is a description of what it is about:

Based on case studies of women who exercised regularly before, during, and after pregnancy, this resource examines the effects of exercise on women and their children. This broad and detailed resource lays to rest the controversies surrounding pregnancy and exercise, shedding new light on the positive interactions of exercise, health, fitness, and pregnancy. This guide enables both expecting mothers and health professionals to develop rational, objective, and individualized approaches to exercise and pregnancy care.

 http://www.amazinglyfit.com