Assertion: sperm's number | /r/CreatedBy | single donor
Facets:
Source sentences:
text: Sperm agencies, in contrast to sperm banks, rarely impose or enforce limits on the number of children which may be produced by a single donor partly because they are not empowered to demand a report of a pregnancy from recipients and are rarely, if ever, able to guarantee that a female may have a subsequent sibling by the donor who was the biological father of her first or earlier children.