In this interview we spoke to Dr Rosemary Leonard about the research and she offers contraception advice too.

Why are some women using the wrong contraception?

It's mainly because they're not aware of their choices or it's to much hassle to try and change.

How would you know if you were using the wrong contraception?

Far to many women rely on taking the same pill that they've always taken. If you're a woman and you're looking after a small baby and you're forgetting to take the pill or you take it late or get mood swings then it's worth thinking is there something that would suit me better. When you've just had a baby, using a long action method of contraception can be a better choice. You take away the daily hassle of having to remember to take a pill.

How long should a woman take the contraceptive pill for?

It is safe to stay with a safe form of contraception. This idea that you have to come off the pill and take a break is rubbish. No you don't. It's far more risky to have an unwanted pregnancy than it is to take the pill.

Can you tell us about the coil as a method of contraception?

There are two very different types of coil. Most women still think of the coils which have copper on them which can last for seven or up to 10 years but they can make your periods heavier and more prolonged which isn't ideal. The mirena device is very different. Instead of having copper it has a progesterone hormone on it and that makes your periods much, much lighter. It's a fantastic method of contracpetion and sadly not many women know about it.

How safe is it to swap and change contraception?

The implant and the coil [the moment they are taken out] within days your fertility returns back to where it was. When you come off the pill it only takes one forgotten pill in some women and they get pregnant. Generally once you stop the pill you are fertile again within a matter of days. For some women it takes longer. The one exception is the injectible one. It can take up to six months before your fertility returns.I suppose the safe option is to not have a gap. Unless of course you want to get pregnant.

The advice given above is just a guide, please consult your own GP or medical practice if you are concerned about what contraception you are using.