how can i

[EdgyExoticReptiles]

tell if my female puget sound is pregnant, she seems to be getting a little fatter

[Sid]

If she is gravid, as she progresses you can feel lumps in her underside. She will be heavier toward the vent as well, not her full length.

[zooplan]

This is extreme but a nice example
http://www.thamnophis.com/forum/thamnophis-contests/855-dons-massive-garter.html

[drache]

I never felt lumps on mine, but she did get noticeably tubbier in the area in front of her vent