Four women are Plenary Speakers at ICM 2018: Nalini Anantharaman, Catherine Goldstein, Sylvia Serfaty and Lai-Sang Young, out of 21 plenary speakers. The proportion of women giving Plenary or Invited Section Lectures at ICM 2018 is 15 %. See a poster on women lecturers at ICM from the origins (presented at the  World Meeting for Women in Mathematics) here.