The interactions between pregnancy and adult-onset Still's disease are unclear. Nine pregnancies which occurred from 1983 through 1991 in seven women (mean age 27.7 years; range 23-40) were studied retrospectively. Five patients had one pregnancy and two had two pregnancies. Onset of the joint disease occurred before or during pregnancy. The joint disease occurred at the 5th or 6th month of the first pregnancy in two patients; one of these patients had a second pregnancy which was not associated with a flare. In five patients, onset of the joint disease occurred 4, 15, 42, 44 and 58 months before the first pregnancy, respectively; any effects of the joint disease on the pregnancy were extremely variable. 6 infants were full-term and two were premature (35 weeks); the remaining pregnancy was electively terminated; Apgar scores were normal in all eight infants, who were all male. Adult-onset Still's disease did not influence the outcome of the pregnancy in our patients; no clear-cut effects of pregnancy on adult-onset Still's disease were seen.