Ovulation when the right side of the waist pain may be caused by the following reasons: First, the right side of the adnexal area of inflammation, ovulation when the follicular fluid will flow to the uterine rectum trap, so it will form a stimulus, the right side of the adnexa itself has inflammation, inflammation itself will be congested and edematous, so it will be stimulated and cause localized pain. Second, the right side of the ovary ovulation, ovulation after the local formation of corpus luteum, relatively speaking, corpus luteum phenomenon, because of increased internal pressure or a small amount of bleeding will lead to localized mild distension and pain, stimulation to the posterior peritoneum will cause localized symptoms of lumbar pain, which is the ovulation period. The right side of the lower back pain suggests timely to the hospital to give examination, according to the results of the examination if there is inflammation actively give anti-inflammatory treatment.