Testing before wedding

Rabbi Orlian:
Some authorities prohibit sperm count testing as a form of wasted seminal emission (hotza'as zera l'vatala). However, most Most halachic authorities allow sperm count testing when absolutely needed for the purpose of procreation. Therefore, if your fiancée refuses to marry you without your being tested first, it is permitted.

However, the semen should be procured in an indirect manner or through the intervention of the doctor, not through masturbation. If this is not possible, some authorities allow even through masturbation.

If you and your fiancée plan on marrying, regardless, the test should not be performed now. It may prove unnecessary. Even if necessary later, it enables the more lenient method of procuring semen through marital relations.

(See Nishmas Avraham E.H. 23:1B(1-2); Igros Moshe E.H 1:70, 2:16; Tzitz Eliezer 9:51[1:2]; Achiezer 3:23; Rav Shlomo Daichovsky, Assia 67-68, pp. 13-18.)

Rabbi Halperin: In conclusion, It is permissible to conduct the test only if it is a strict condition of your fiancée, without which she will cancel the engagement.