Different people have different reactions to various BC pills. Some people tolerate them and some don't - I'm one of the "don'ts". I took ortho tricyclen about 7 years ago and had a number of bad side effects, namely extreme mood swings, weight gain, constant hunger/stomach growling, melasma (brown patches on face), and it killed my libido.
Before that scares you off, let me say I'm not a normal person to begin with. For one thing, I was already taking Prozac for eating disorder and depression. I had to triple my Prozac dose when I went on the BC pill, because of the mood swings it caused.
Although various studies say the pill doesn't make women gain weight, I (and many others) say otherwise. (These "studies" were probably funded by companies who make the pill...
) Anyway, I believe something in the Pill made my body store fat more easily. Being already so conscious of my weight, I did not allow myself to eat more food. I even increased my exercise, but my weight kept climbing.
Many people say Prozac makes them gain weight, but it helped me lose weight because I no longer starved/binged. My weight had been stable for years when I went on the BC Pill. Same with the libido. I'd never had a high one, but it was still there through years of Prozac. When I started the Pill, I didn't want my husband anywhere near me.
Because of the side effects, I switched to Triphasil, but it was just as bad. Now I use an IUD and feel back to normal. That's my experience in a nutshell. I'm probably a worst-case scenario due to my other issues. My hormones were probably already in a fragile state, and adding the Pill was too much for me.