Simply put SRHR is a subset of the Right to Health. SRHR include freedom from sexual violence, maternal health care, the freedom to choose a sexual partner, whether or not to have children, and reproductive health care, among others.
Important to note is that International Human Rights law recognizes SRHR in the CEDAW(Article 16, etc, Maputo Protocol (especially in Article 14), CESCR General Comment 14, just to mention but a few.