By Caroline Ryan
BBC News Online health staff in Berlin
German scientists must address the taboo of Nazi fertility research in order to make progress in the future, a researcher has warned.
Current research is being affected, it is claimed
Professor Rolf Winau of the Medical University in Berlin says German experts have "the shadow of eugenics hanging over them".
He believes this has led to the country having some of the strictest laws on human reproduction in Europe.
He will issue his warning to a major fertility conference in Berlin.
Professor Winau will tell the European Society of Human Reproduction and Embryology conference that if the Nazis' work is not understood, German researchers will struggle to decide on ethical issues confronting experts working in gynaecology, embryology and reproduction.
He is set to say: "This research should not be about blaming or accusing individuals long after the event, but should shed light on how and why professionals in a particular branch of medicine behaved.
"Knowledge about such behaviour is as important as the knowledge about the success of scientific medicine.
"Only this knowledge will make it possible to reflect on our present situation."
Egg donor ban
German law currently does not allow couples to undergo preimplantation genetic diagnosis, which can detect genetic diseases in an embryo before it is transferred to a woman.
In addition, embryos cannot be frozen for use at a later stage.
Professor Winau says this has led to Germany having one of the higher rates of multiple births in Europe, because doctors have to transfer all the embryos they manage to create, regardless of their quality.
Forty per cent of all IVF births in Germany are multiple births. However, multiple births carry risks for both the mother and the babies.
The country has also banned surrogacy and egg donation.
Professor Winau, professor of the history of medicine at Charite (the medical university in Berlin), said: "From 1952 to 1980 there was no research at all into medicine during the Nazi era.
"Today, there are still a great number of doctors who do not wish to be 'disturbed' by remembering the dark times of German medicine. Only a few hospitals have faced up to their history."
He said many researchers working during the Nazi era seized on the opportunities offered by the regime to pursue their research.
Over 45% of German doctors at the time were Nazis and some even worked as researchers in the concentration camps.
"Not all who used this opportunity did so from unscrupulous motives; however, for many scientists, the scientific impetus triumphed over ethical scruples.
"This definitely goes for the anatomist Hermann Stieve, who undertook a fundamental examination of ovulation in executed women from the Ploetzensee prison between 1942 and 1944.
"His scientific thirst for knowledge led to him seizing the opportunities offered to him without questioning them."
Professor Winau said the magnitude of the crimes committed by these men, and many others, means it is vital to understand why they behaved in the way that they did.
He added: "We need to study the 'Rassenhygiene', the German version of eugenics, in order to show how far eugenic and racial thinking can go, so that we can have it in mind when we discuss ethical questions on reproduction and fertility.
"If we do not, we face uncertainty, lack of information and confusion when considering ethical questions in the future."
Professor Winau added: "It is time to deal with this issue in universities, on courses and in society."