Weight gain is just as common on Yaz as it is on Ortho, to my knowledge. But not extremely common on either, so I wouldn't worry, especially if you're worried about weight loss now.

Birth control pills can cause bowel side effects, that is normal. I haven't heard of anything that extreme though, and if you think it is the pill causing it I would definitely switch.

I hope it gets better.

We were able to link my severe stomach issues (IBS, acid reflux, stomach spasmodia, and "unexplained nausea") to YAZ. I've been off it now for a while and haven't had a single stomach problem since going off it. My stomach issues were a DAILY issue prior to going off the YAZ and looking back at my medical history, they started right around the time I started on YAZ. I didn't link it with the YAZ at first because I didn't know YAZ could cause GI symptoms. I was seeing a GI doctor who never mentioned a possible link. It was a friend that mentioned the link so I talked to my OB/GYN and sure enough. I'm off BC completely now because I'm trying to get pregnant, but I have had luck in the past with Ortho-Tricyclen (also tried the ortho-tri-lo but had break through bleeding). I was on ortho-tri for over 5 years and never experienced weight gain, acne, headaches or stomach issues. Medication have different effects on different people, but you could also talk it over with you OB/GYN.

I too would get nauseated randomly on yaz but only for the first 2 months(2 pill packs)...if you read the pack it says that this can be one of the side effects but the side effects shoult subside within 3 packs...so i decided that before going back to the dr and switching pills i'd wait out the 3 months...after 3 months all nausea and random headaches went away..my body adjusted fine..i'm still on yaz and love it...how long were you on yaz before you went off of it?