Nikitaji, I advise this book Nawa Yogini Tantra by Swami Muktananda for the Bihar school of yoga (Rs 100) available with Landmark bookstores. You will find Landmark on the net, and locate addresses close to your home, for delivery. It is a book on yoga for women and has a full chapter on pregnancy. It is an excellent section dealing with specific needs of a woman during each trimester. I am recommending it for the relaxation techniques it suggests, and breathing practices. In olden times, in Maharastra, it is said midwives used to train women in yoga so the babies born were sweet-tempered, Buddha-babies! So, this book will help you with such insight to get the right frame and advise you on the nature of activity recommended for each trimester. Also, there are meditation tapes done by some companies which you may find interesting: Garba sanskar by times music for instance.