undergoing medical procedures for the sake of the spouse's fertility

Shalom
A woman is permitted to put herself through surgery for the sake of having children with her husband if the risk is not high, for a number of reasons. First, the woman also benefits from having children. Second, although she does not have a formal obligation of pru ur'vu, according to many authorities she is included in the human responsibility to populate the world (shevet) and fulfills a mitzvah by bearing children. (Tosfos Gittin 41b s.v. lo; Otzar Haposkim E.H. 1:13:84) Thirdly, she has a responsibility to enable husband to fulfill mitzvot according to her ability, certainly in the area of fertility.
If she is single and faces radiation/chemo, it is recommended that she undergo oocyte retrieval to allow her to conceive with her own eggs.

With blessing,
Meir Orlian