An article posted in the Journal of the American Medical Association identified that some of the highest-ranking health apps used to assist people with mental health conditions (e.g. depression) and smoking cessation were sharing data with Facebook and Google services and that only a third disclosed such practices.

From the HHS Office for Civil Rights website: Ask your doctor. You have the right to see and get copies of your health information - PDF. In most cases, you can get a copy the way you want it, such as by e-mail. While your doctor normally has up to 30 days to provide you a copy of your information, your doctor often can provide the information much sooner than that. If your doctor offers a web portal, you may be able to easily view and download your health information whenever you want.

Abstract from the article titled, "Before Using Birth Control Apps Consider Your Privacy" posted on Wired.com: "Natural Cycles’ privacy policy states that in using the app each user grants the company and any of its partners broad rights to “use, reproduce, distribute, modify, adapt, prepare derivative works of, publicly display, publicly perform, communicate to the public, and otherwise utilize and exploit a user's anonymized information.”