Was Hedda really pregnant?

So, all throughout the book, it was hinted that Hedda was pregnant. It started when George was being all excited about Hedda body "filling out." That normally happens when a woman is pregnant or going through puberty, which I'm sure Hedda has already done LOL. It continues all those times when Aunt Julie says that Hedda has something to tell George. So, was Hedda really pregnant or was she just getting thick? Was Aunt Julie's instinct right, or was she just wrongly assuming? IDK...I really want to know though because if she was, that was OC of her to kill herself and never tell anyone about the baby or anything. And if she was, why didn't she acknowledge that?