Unilateral Blaschkoid lichen planus in successive pregnancies.

A number of genetic, congenital and acquired dermatoses have been known to follow Blaschko's lines. A common disorder like lichen planus can very rarely present with pruritic lesions in atypical patterns such as unilateral distribution, painful eruptions and along Blaschko's lines. Various triggering factors varying from viral infections and vaccinations to trauma have been implicated in lichen planus. We describe a female patient in the second trimester of her second pregnancy who developed unilateral lichen planus along Blaschko's lines during both pregnancies. No case of lichen planus along Blaschko's lines recurring during pregnancy is reported so far. Could pregnancy itself be a contributory factor towards onset of lichen planus in this case?