Im on kariva to regulate my period. I just have a random question. Would it cause my breasts to get bigger, and to gain weight?

In short yes. Here are the side effects you should be aware of. Questions like this can be found by doing an internet search. Hope it helped!

Serious Side Effects:
chest pain; coughing up blood; dizziness or fainting spells; leg, arm or groin pain; severe or sudden headaches; stomach pain (severe); sudden shortness of breath; sudden loss of coordination, especially on one side of the body; swelling of the hands, feet or ankles, or rapid weight gain; vision or speech problems; weakness or numbness in the arms or legs, especially on one side of the body
Contact Your Doctor Side Effects:
breast tissue changes or discharge; changes in vaginal bleeding during your period or between your periods; headaches or migraines; increases in blood sugar, especially if you have diabetes; increases in blood pressure, especially if you are known to have high blood pressure; symptoms of vaginal infection (itching, irritation or unusual discharge); tenderness in the upper abdomen; vomiting; yellowing of the eyes or skin

Notify if bothersome or continue:
breakthrough bleeding and spotting that continues beyond the 3 initial cycles of pills; breast tenderness; mild stomach upset; mood changes, anxiety, depression, frustration, anger, or emotional outbursts; increased or decreased appetite; increased sensitivity to sun or ultraviolet light; nausea; skin rash, acne, or brown spots on the skin; tiredness; weight gain

I've taken kariva since 2002. When I started I weighed 100 lbs (I am 5'6) and was somewhere between a B and C. In the last 4 years I have gained maybe 12 lbs and a full cup size. (I think the weight gain is more due to being less active--I did lots of sports in high school, and I graduated in 2002). Another good things..My periods are very light and last only 3 days (wed-fri, I am "sunday start").

I have been on Kariva for 3 years now and I love it!! I have actually lost weight and yes.....my boobs have grown some too! I was a C cup before and I'm still a C cup now, but I can defenitely tell that my boobs are more pronounced than before (I have a little more cleavage now! :p ) LOL! But hey....I'm not complaining!