Association between COVID-19 lockdown measures and the incidence of iatrogenic versus spontaneous very preterm births in the Netherlands: a retrospective study

J. Klumper^*, B. M. Kazemier, J. V. Been, K. W.M. Bloemenkamp, M. A. de Boer, J. J.H.M. Erwich, W. Heidema, F. J.C.M. Klumper, S. W.A.Nij Bijvank, S. G. Oei, M. A. Oudijk, S. Schoenmakers, A. S. van Teeffelen, C. J.M. de Groot