Aiyoh mama, discharge with slight yellow tinge is actually quite normal in pregnancy, hormones go crazy and everything changes down there! A few of us mummies had the same thing and it worried us for nothing, but since the nurse mentioned the colour, best to ask her if she wants to do a quick swab test just to be safe, ya? Kputihan is super common when pregnant but better safe than sorry especially first time around, and if it's causing discomfort or smells off, the doctor can give you something gentle that's safe for baby. Don't worry yourself too much, you're doing the right thing by asking and being honest with your nurse!