For the purpose of ascertaining whether the membership of a class is presently
ascertainable and, if so, the membership of the class—
(a) the
possibility that a person might, while under the age of 12 years, become the
natural or adoptive parent of a child is to be ignored; and
(b) the
possibility that a male or female over the age of 55 years might become the
adoptive parent of a child is to be ignored; and
(c) the
possibility that a female over the age of 55 years might bear a child is to be
ignored; and
(d) the
possibility that a child might be born to a living person is to be ignored if
it is established to the satisfaction of the court that there is no real
prospect that the possibility will be realised; and
(e) the
possibility of biological parentage arising from an artificial reproductive
procedure involving the use of reproductive material from a person who is dead
at the time of the procedure is to be ignored.