birth controls and weight gain?

Hey guys!  I am currently on a birth control pill.  I have been experiencing some weight gain and I'm really upset about it.  I have always worked very hard to get the results I want and the pill just seemed to ruin it 😕.  Does anyone know whether the IUD or Implant Nexplanon is better with weight gain?  I just want to get results after such hard work 😞.