OBJECTIVES: Psoriasis treatment in pregnant women requires weighing the risks and benefits to both mother and fetus. Little is known about how psoriasis is treated during pregnancy. This study sought to identify the medications most commonly prescribed in this situation. METHODS: The Truven 2003-2007 MarketScan™ Medicaid Database was used. Pregnant women with psoriasis were identified by inpatient and outpatient records. The investigators created an algorithm to identify eligible pregnant women and approximated their gestational periods using this claims database to identify drug use during pregnancies. The prevalence of drug use was determined by the proportion of prescriptions. The top 10 most popular prescriptions as well as methotrexate were identified based on the proportion overall and by trimester of pregnancy. Use of topical corticosteroids were revealed by drug potency.  RESULTS: Based on the algorithm created by the investigators, 974 pregnant women with psoriasis were identified, and 386 (39.6%) of them filled psoriasis drugs and saw a physician for psoriasis before pregnancy. The most common medications prescribed most patients were topical corticosteroids (n=122, 31.6%). Of those patients given topical corticosteroids, the majority were low to mid-potency (64.8%). The second most common drug type (n=41, 10.4%) used was “other” products such as topical vitamin-D analogues and pimecrolimus. This was followed by biologics (n=2, 0.5%) and other systemic treatments (n=2, 0.5%). Two patients received methotrexate during their pregnancy- one of which received it for the entire gestational period.  CONCLUSIONS: This study revealed the prevalence of psoriasis medications used in pregnant women with psoriasis, which could provide information in how risks and benefits of psoriasis treatment in pregnant women were weighed. In general, dermatologist prescribing patterns were in line with treatment recommendations for pregnant women. However, there were some treatments prescribed that were not suitable for pregnant women. Care should be to ensure safe treatments for pregnant women.