There have been a lot of stories like this in the news over the past couple of years, for example: https://www.telegraph.co.uk/news/9193014/British-man-fathere

There have been a lot of stories like this in the news over the past couple of years, for example: https://www.telegraph.co.uk/news/9193014/British-man-fathered-600-children-at-own-fertility-clinic.html https://www.telegraph.co.uk/news/9193014/British-man-fathere... https://edition.cnn.com/2016/09/13/health/fertility-doctor-impregnate-patients/index.html https://edition.cnn.com/2016/09/13/health/fertility-doctor-i... http://www.dailymail.co.uk/news/article-4504648/Head-Dutch-clinic-used-sperm-father-kids.html http://www.dailymail.co.uk/news/article-4504648/Head-Dutch-c... http://www.rebelcircus.com/blog/fertility-doctor-used-sperm-secretly-father-least-19-children/ http://www.rebelcircus.com/blog/fertility-doctor-used-sperm-... https://news.sky.com/story/dna-of-fertility-clinic-doctor-accused-of-using-his-own-sperm-can-be-tested-10902314 https://news.sky.com/story/dna-of-fertility-clinic-doctor-ac... Shocking how frequent this behaviour appears to be.