[header] How to find out if your guppy is pregnant [title] Notice a belly bulge. [step] Like women, the female guppy will get larger, as if it's being inflated. Sometimes this can just be bloating and not pregnancy. 
But if you monitor your guppy's belly for several weeks and it continues to get bigger over time, your guppy is probably pregnant. [substeps] Your female guppy is getting close to delivery time when the she is very large and has a boxy appearance.