Clinical course of psoriasis during pregnancy

Since the landmark study on rheumatoid arthritis, many reports have suggested that physiological changes during pregnancy often induce remission of systemic and cutaneous inflammatory diseases. In this study we investigated the clinical course of psoriasis during pregnancy.

In this retrospective study information was collected from Psoriasis Life History Questionnaires. The data obtained from 736 questionnaires were entered into a computerized database. Information relevant to the clinical course of psoriasis during pregnancy was evaluated in respect to improvement/worsening, number of pregnancies, severity of the disease, and certain other clinical parameters.

In a majority of the patients psoriasis improved during pregnancy. Data available from 91 pregnancies revealed: psoriasis improved in 51 (56%), worsened in 24 (26.4%), and remained unchanged in 16 (17.6%). Also, appearance of psoriasis new lesions was found to be frequent during the early postpartum period. Patients who improved in the first pregnancy were found to have a similar response in the following pregnancies.

Research on immuno-endocrine interactions during pregnancy is a relatively new field. Proinflammatory Th-1 cytokines are up-regulated in psoriasis and play a key role in the inflammatory cascades of psoriasis. It is likely that during pregnancy the Th-2 cytokine-mediated down-regulation of the immune response by virtue of its anti-inflammatory and antagonizing effects on the Th-1 cytokines improves psoriasis.