Menstrual cycle characteristics in fertile women from Greenland, Poland and Ukraine exposed to perfluorinated chemicals: a cross-sectional study

J Lyngsø, C H Ramlau-Hansen, B B Høyer, H Støvring, J P Bonde, B A G Jönsson, C H Lindh, H S Pedersen, J K Ludwicki, V Zviezdai, G Toft