Anorgasmia is the medical term for regular difficulty reaching orgasm after ample sexual stimulation, causing you personal distress. Anorgasmia is a common occurrence, affecting a significant number of women.
Orgasms vary in intensity, and women vary in the frequency of their orgasms and the amount of stimulation necessary to trigger an orgasm. In fact, most women don't consistently have orgasms with vaginal penetration alone. Plus, orgasms often change with age, medical issues or medications you're taking.
If you're happy with the climax of your sexual activities, there's no need for concern. However, if you're bothered by lack of orgasm or the intensity of your orgasms, talk to your doctor about anorgasmia. Lifestyle changes and sex therapy may help.