It probably is NOT amniotic fluid, but best to ask your midwife. Amniotic fluid has a distinct sweet smell to it, unlike semen which we all know what that smells like, but I cannot even describe the smell of semen. I know this is TMI, but now that I am further along in this pregnancy, I am getting more discharge that sometimes wets my underwear too that smells like semen, but it is NOT semen as me and hubby have sex but once a week (and cannot leave it inside anyway according to doctor) and when I noticed the smell it had been a week since we did it. If you have never smelled amniotic fluid, you wouldn't know and it is hard to describe lol Amniotic fluid can be clear or bloody or a variety of things depending what's going on inside, so don't go by the fact it wasn't bloody. When mine broke with 2 of my kids previous, it was not bloody. If it happens more than a few times a day and your underwear are drenched, I'd get it checked.