Increased rate of primary dysmenorrhea in women with spontaneous premature labor.

Prostaglandins (PG) are responsible for primary dysmenorrhea and may be involved in the start of preterm or fullterm labor. Therefore, in order to see if there is any association between these two PG-mediate conditions, the incidence of dysmenorrhea in 177 primiparous women with threatened premature labor was compared with that in 177 primiparous women without premature uterine contractions. Dysmenorrhea had occurred about two times more commonly in women with threatened or established premature labor than in the controls. If this finding is confirmed in prospective studies, dysmenorrhea should be regarded as a factor predisposing women to a premature labors.