Access your Endocrinology Medical Group Of Orange County patient portal. Address . 725 W. LaVeta Ave, Ste. 220, Orange, CA. Office Hours: 7:30am – 4:30pm (Mon-Fri) Office Number (714) 771-5700. Fax: (714) 771-9977. ... "My experience with Dr. Shah and the endocrinology medical group staff has been wonderful, I would highly recommend ....