Pregnancies with multiples can be selectively aborted, leaving one or two.
Lots of folks that have taken fertility drugs do end up getting rid of a couple of "fetuses".
Once a high order multiple pregnancy is established, selective reductions often make a lot of medical sense, both for the mother and especially for the babies -- the latter being very likely to all get miscarried or at least severely disabled by a combination of crowding and prematurity, if there is no reduction. However, selective reductions are not without risk (sometimes causing the miscarriage of any remaining fetuses), and going about fertility treatments in a way likely to cause high order multiples, thinking that you can always get rid of the extras if there are extras, does NOT make medical sense. It is very easy to do fertility treatments with no risk of high order multiples, but it costs more.