Note: Postings to Androlog have been lightly edited before publication.

Medical practice varies regionally, and this variation is often most apparent in the field of reproductive medicine. Regarding the use of donor sperm for human artificial reproductive techniques, Sharon Warner asks:

What is the maximum number of babies/families permitted or recommended per semen donor in each country? Are these limits set by guidelines, legislation, or best practice? And are these limits based on the general population of the country, social concerns, or the donor's request?

For Denmark, Ole Schou replies:

According to the Guideline from the Danish National Board of Health: 25 pregnancies geographical spread (in the Danish population of approximately 5.3 million citizen) + siblings. Export on top of this. No total limits. We have donors with greater than 100 pregnancies reported.

Ulrik Kvist replies for Sweden:

6 + siblings.

For Norway, Trine Haugen answers 6.

Lars Bjorndahl replies for the United Kingdom:

10 donor children + siblings. Regulated and supervised by the Human Fertilization and Embryology Authority (HFEA,

Carlos Garcia-Ochoa and Ernesto Veiga Alvarez answer for Spain:

According to the Spanish Law, the maximum number of babies allowed is 6 for each donor. Law 35/1988, 23 November, about Assisted Reproduction Techniques: maximum of 6 born babies per donor (semen or oocytes), include own babies.

For Brazil, Sidney Glina answers:

Federal Council of Physicians recommended in 1992 the maximum of 10 born babies per donor.

Walter Cardona-Maya answers for Columbia:

According to the Colombian Law (DECRETO NUMERO 1546 DE 1998), the maximum number of babies allowed is 10 for each donor.

Individual policies regarding the maximum number of offspring per sperm donor would most sensibly result from a survey of population density and genetic diversity, concepts that Dr Warner addresses in her initial query. Interestingly, none of the replies cite such a basis for legislation in reporting the maximum number selected for each country. Aside from serving as an interesting survey of regional differences in one aspect of artificial reproductive technology, this thread provides a reminder that even legislated medical guidelines may be as much about art as they are about science.