AI-assisted Total Body Dermoscopic Evaluation of Changes in Melanocytic Nevi during Pregnancy: A Prospective, Comparative Study of 2,799 Nevi

Acta Derm Venereol. 2025 Jan 3:105:adv41025. doi: 10.2340/actadv.v105.41025.

Abstract

Pregnancy-associated changes in melanocytic nevi (MN), apart from size increase on the trunk, remain a topic of debate. We conducted the first prospective study to investigate dermoscopic changes in MN comparing pregnant with non-pregnant women on all body parts using a market-approved convolutional neural network (CNN). We included 25 pregnant and 25 non-pregnant women from Basel, Switzerland, who underwent standard skin cancer screenings and whose MN > 2 mm were digitally recorded and analysed by a CNN. Pregnant women were examined three times: in the first and third trimester and 8-12 weeks postpartum; non-pregnant women twice in an interval of 17-21 weeks. We analysed 2,799 MN. In pregnant women, diameter[p < 0.001], area[p < 0.001], number of colours [p = 0.009], shape asymmetry[p = 0.005] and border sharpness[p = 0.006] (inversely proportional value) increased while ellipseness [p < 0.001] decreased from first trimester to postpartum. Changes occurred mainly during the third trimester to postpartum. Compared to non-pregnant women (only first to third trimester) MN on the upper extremities of pregnant women increased in area[p = 0.011] and diameter[p = 0.025] and decreased in ellipseness[p = 0.037]. MN on the lower extremities increased in area[p = 0.044] and MN on the back increased in colour asymmetry[p = 0.022].

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Case-Control Studies
  • Dermoscopy*
  • Female
  • Humans
  • Neural Networks, Computer
  • Nevus, Pigmented* / diagnostic imaging
  • Nevus, Pigmented* / pathology
  • Postpartum Period
  • Predictive Value of Tests
  • Pregnancy
  • Pregnancy Complications, Neoplastic* / diagnostic imaging
  • Pregnancy Complications, Neoplastic* / pathology
  • Prospective Studies
  • Skin Neoplasms* / pathology
  • Switzerland
  • Young Adult

Grants and funding

Founding sources This research project was funded by the Department of Dermatology of the University Hospital of Basel, as well as in minor part by the Voluntary Academic Society Grant, Basel, Switzerland. FotoFinder ATBM® Systems GmbH did not have the opportunity to comment on or influence the results or manuscript of the study.