most side effects are weight gain, periods stopping or increasing and excessive sweating. it depends how old you are. my sis got one she is 19 and her periods lasted so long and got that bad that she now has to take the pill aswell as having the implant just to regulate her periods, she also experienced major excessive sweating whereas before she was the type of person who could sit on a radiator and still be freezing. i would say if your over 21 ask for a coil. the pill is fine but can easily be forgotten and thats when things go wrong, at least with the coil you can pretty much forget about it for 5 yrs and it really reduces your periods which is great. the injection contraceptive is just as bad if not worse than the implant. i had jab twice before my coil and put on loads of weight which im still struggling to shift.