yep its generally called Evra its a small square plaster that looks kind of like a nicotine patch, The patch releases two hormones, oestrogen and progestogen into the bloodstream through the skin. Like the combined pill it stops the ovaries from releasing an egg for fertilisation every month. It also thickens the mucus around the cervix, which makes it difficult for sperm to get into the womb.
i used to stick mine on my thigh, it wont come off in the bath or whilst swimming they are mega mega sticky.
you put the patch on the first day of bleeding then on the 7th day you take the patch off and put a new one on right away, you do this for 3 weeks then on the third week you dont use a patch so that you have a 'period' just the same as the pill but youo dont have to remmeber to take a pill every day.
when i was on the patch i used to get little stickers saying 'patch 1' 'patch 2' 'patch' 3 to stick on the calender so i didnt forget when to change it.
i never had any problems with this form of contraception. im pretty sure the restrictions with the patch are the same as the pill so if you have high bp or are really over weight they prob wont give it to you.
its 98% effective against pregnancy but remember it wont stop you from catching stds, theres a sticky at the top of the teen section written by me all about condoms that you may also find useful
take care and stay safe