Fascinating immunologic mechanisms that are crucial for pregnancy can, however, lead to the development of different skin conditions, of which atopic dermatitis (AD) is the most frequent one. AD in pregnancy may occur de novo or as a recurrence or exacerbation of known chronic AD. The changes in hormone levels that occur during pregnancy influence the cytokine balance and can lead to manifestation of eczematous lesions, currently classified as atopic eruption of pregnancy. The diagnosis of atopic eruption of pregnancy may be challenging, especially in patients who developed this skin disease de novo during gestation. The treatment is another challenge, because it needs to be safe for both the mother and especially the unborn child. Emollients make up the basis of the therapy. Topical corticosteroids and calcineurin inhibitors are also safe treatment options, and ultraviolet therapy can be added, if required. Use of cyclosporin A is possible for systemic therapy during pregnancy, whereas safety data on new drugs such as biologics approved for AD are limited to small case series. This review is aimed at summarizing available data on the mechanisms that lead to AD during gestation, differential diagnostic evaluations, and treatment options.