Dysmenorrhea is most likely to occur in which of the following patients?

Dysmenorrhea, which refers to painful menstrual cramps, is most commonly seen in women who have regular menstrual cycles, usually affecting those in their late teens to early 30s. In this context, the 35-year-old woman with regular cycles is likely to experience dysmenorrhea as she falls within the age group where this condition is prevalent.

Regular cycles often indicate that the hormonal balance is intact, and pain associated with menstruation can occur due to increased prostaglandin production, which leads to uterine contractions and discomfort. Older adolescents and women in their reproductive years are more likely to experience this pain because their bodies are regularly responding to the cyclical changes of the menstrual cycle.

The other scenarios provided do not typically prompt the same likelihood of dysmenorrhea. A young teenager who has just started menstruating may experience irregularities and infrequent cycles, which can sometimes lead to less pronounced symptoms as her body adjusts. A woman on birth control pills often experiences lighter, shorter periods and reduced menstrual pain due to hormonal regulation. Lastly, a marathon runner with infrequent menstruation (only once a year) could be experiencing athletic amenorrhea, thus reducing the opportunity for dysmenorrhea to occur altogether.