No, there are no connections between using peptides and fertility. If the woman finds it hard to get pregnant, it's possible that she has problems with her reproductive system, and like what peptidenoob has said, it's also possible that it's the guy who can't get the woman pregnant.
It does not affect your fertility. Peptides induce a natural GH pulse. Unless your peptides are something that's really different, then you should not worry about anything.
There isn't any negative feedback caused by using peptides when it comes to fertility. They just effectively improve the body's ability to produce GH. Consider it a test booster that really does what it claims.