DNA databases Even sperm donors who have chosen anonymity and not to contact their offspring through a registry are now increasingly being traced by their children. Improved DNA technology has brought into question the possibility of assuring a donor's anonymity. Due to an increase in popularity of DNA testing, it has become relatively easy to identify one's sperm donor. Even matches at a third or fourth cousin level can provide clues which enable one to identify their biological father. It has become common practice for donor conceived people (who were conceived via an anonymous sperm donor) to ascertain who their biological father is via this method. For example, at least one child found his biological father using his own DNA test and internet research and was able to identify and contact his anonymous donor. Fertility tourism and international sperm markets Different factors motivate individuals to seek sperm from outside their home state. For example, some jurisdictions do not allow unmarried women to receive donor sperm. Jurisdictional regulatory choices as well as cultural factors that discourage sperm donation have also led to international fertility tourism and sperm markets. Sweden When Sweden banned anonymous sperm donation in 1980, the number of active sperm donors dropped from approximately 200 to 30. Sweden now has an 18-month waiting list for donor sperm. At least 250 Swedish sperm recipients travel to Denmark annually for insemination. Some of this is also due to the fact that Denmark also allows single women to be inseminated. United Kingdom After the United Kingdom ended anonymous sperm donation in 2005, the numbers of sperm donors went up, reversing a three-year decline. However, there is still a shortage, and some doctors have suggested raising the limit of children per donor. Some UK clinics import sperm from Scandinavia. Despite the shortage, sperm exports from the UK are legal and donors may remain anonymous in this context. However, the HFEA does impose safeguards on the export of sperm, such as that it must be exported to fertility clinics only and that the result of any treatment must be traceable. The number of pregnancies obtained from an individual donor in each country where his sperm is exported will be subject to any local or national rules which apply. In addition, UK sperm banks may apply their own global maximum for the number of pregnancies obtained in respect of each donor. Since 2009, the import