CHANGES IN SIZE OF MELANOCYTIC NEVI DURING PREGNANCY

Background: The relation between pregnancy, melanocytic nevi, and mali gnant melanoma is ambiguous. It has been reported that nevi grow and d arken during pregnancy. Several recent studies have shown that maligna nt melanomas diagnosed during pregnancy are thicker than those not ass ociated with pregnancy. This may be partially due to a delay in diagno sis because of the opinion that benign nevi change during pregnancy. O bjective: Our purpose was to photographically document any change in s ize of melanocytic nevi during pregnancy. Methods: Twenty-two women we re entered into the study during the first trimester of pregnancy and examined again in the third trimester. All nevi 2 mm or larger on thei r back were documented and photographed. Photographs were then compare d and nevi measured for change in diameter. Results: Of 129 nevi, only eight nevi (6.2%) changed in diameter from the first to the third tri mester. The mean change in size of all nevi studied was zero. Of the e ight nevi that did change in size, four increased by 1 mm and four dec reased by 1 mm. Conclusion: Our study suggests that pregnancy is not a ssociated with any significant change in size of melanocytic nevi. Pat ient characteristics (age, pregnancy number, skin type) and nevi chara cteristics (location, number) did not correlate with any change in siz e.