The attending physician must complete the form for the registration of sperm donor data (in accordance with Art. 16 RMO) and, immediately after the birth of a sperm-donor-conceived child, transmit it to the Federal Office for Civil Registration (EAZW) (sperm donor file). This notification is thus to be made whenever an assisted reproductive technique involving donated sperm cells has been successful. Also to be reported is the child's date of birth or ― if the exact date is not known — the probable date of birth (Art. 25 RMA in conjunction with Art. 16 RMO).  ●  The chart shows the number of registered sperm donors as per the reference date of each year (31 December) since the register was created. Any differences in comparison to previously published figures may be due to subsequently identified duplicate sperm donor registrations.

 
Source: EAZW donor data registry