Maire Bonheim quizzed Dr Catherine Hood, the Sunday Mirror’s Sex Doctor, about the risks involved in taking the Pill, just how effective it is at preventing pregnancy, and whether it really is to blame for weight gain.

Just a third of women understand the effects of the hormones they are putting into their bodies every day when they take the contraceptive Pill. The Pill is the most common form of contraceptive, used by a massive 3.5 million women in the UK alone. Yet most are unaware of the possible risks and side effects, or that by simply swapping to another option they could eliminate those effects.

Why are so many women in the dark about the Pill when it affects them so directly?

Lots of women take the Pill for granted – it’s been with us now for 40 years and we’ve got used to it. It has fantastic protective benefit in terms of contraception, but I think women are unaware that there are many types or preparations of Pills. A recent survey done by Bayer Schering Pharma among women who were taking the Pill or had taken it in the past showed that there was a huge knowledge gap in that only a third of women really had any idea of the impact that these hormones could have on their body – whereas the majority of women were perfectly aware of what was in their evening meal, and the effects the fats and calories could have on their body.

So what effect do the hormones in contraceptive Pills have?

Well, basically when you take the Pill you’re taking two hormones that are very similar to your own natural hormones that regulate your menstrual cycle, and the first thing that happens is that the tablets trick your body into thinking that you’re pregnant so that you won’t ovulate – that’s why it’s a very good form of contraception. But when you’re taking hormones, like any drugs, there are some side effects, particularly taking the hormone called oestrogen. There are serious potential side effects – the oestrogen can make your blood prone to clotting and there can be issues with breast cancer, but there are also protective benefits that come with the pill – it protects you against certain types of cancer, like endometrial and ovarian cancer, and obviously protects you from pregnancy. So there’s a real balance you have to take when you’re deciding whether to go on the Pill; great benefits balanced against potential risks.

Do you think the Pill is responsible for increased cases of breast cancer?

I think there’s no evidence to show that that is the case. Certainly the Pill’s oestrogen can very minorly increase your risk of breast problems while you are taking them, but that risk is shown to disappear ten years after you’ve stopped taking the tablets, so as long as you only take the Pill at a young age when your risk is very small anyway, then the increased risk is negligible. You do really have to take advice though if you have got someone in your family who has suffered from breast cancer or breast disease. Talk very closely with your GP or specialist at the hospital about whether the Pill is appropriate for you, because there are other contraceptive options - there’s a lot available out there.

Could you explain the types of Pills available?

Broadly speaking you’ve got the Combined Pill and the Progesterone Only Pill. The Combined Pill contains oestrogen and progesterone, and there are different preparations of the Combined Pill. Then you have what used to be called the Mini-Pill, or the Progesterone Only Pill, that only contains one hormone. Broadly speaking they’re the two main categories of Pill.

What are the most common side effects of the hormones in the Pill?

Things like breast pain, breakthrough bleeding, mood swings and bloating – and while they are minor in that they’re not big health risks, they can be incredibly irritating. But women don’t have to put up with them; often switching to a different preparation with a slightly different mix of hormones can improve those side effects, so it’s worth going back to talk to your doctor or family planning clinic and trying a few different preparations to see if there is one that will suit you best and fit in with your lifestyle. I think what would be sad if someone was getting minor side effects and these side effects were putting them off using the Pill altogether, because it is a really good way to protect yourself from unwanted pregnancy.

Should some people avoid the Pill altogether?

Yes, there are certainly some people who medically speaking shouldn’t be on the Pill, for example people who are at risk of thrombosis, which is where you get clots in the lungs –so if you have a family history of that, also people who have migraines or maybe high blood pressure. Sometimes there are health problems that just need a bit of monitoring. That’s why it’s important to go and talk to your doctor before you go on the Pill.

Why do Pills cause different reactions to different people?

We don’t really know, but we do know that when people get side effects, sometimes they disappear if they just keep on the Pill for a few months. Whereas with other people, one particular Pill won’t suit them and switching to another Pill will make them feel a lot better.

Which Pills are best for clearing up skin?

There are a couple of Pills that are very effective, one is Dianette and another is Yasmin. Marvelon is also quite good. They tend to be anti-androgenic, reducing the progesterone side of the hormone balance.

Which are least likely to cause weight gain?

Actually the weight gain story is quite interesting, because it is one of the myths around the Pill. Research shows that the pill doesn’t actually cause people to put on weight – it may make you feel bloated because there is a tendency to retain fluids, and again switching to a different preparation can minimise that. I think the Pill often gets blamed when it’s just people getting older and maybe eating a bit more than they used to!

Which pills are least likely to cause headaches?

Headaches are quite complex, and it’s very important if you do get headaches to talk to your GP, because it may mean the Pill is not the best thing for you in the long run.

Does taking the Pill long-term reduce your chances of falling pregnant?

No. There’s good research to show that your fertility springs back to normal within months of coming off the Pill. It’s a common myth that the Pill will cause infertility and lots of research has shown that it doesn’t – what people often find is that they come off the Pill and suddenly their periods become irregular, and that’s because the Pill actually stops your natural menstrual cycle, and masks the fact that naturally you have an irregular cycle. Bear in mind that as you get older, your natural fertility falls anyway so a lot of women will tend to be on the pill and are only ready to start a family in their mid 30s, and are finding their natural fertility may have fallen by that stage, which has nothing to do with the Pill.

What are some other common myths?

One of the other myths is that you can’t be on the Pill for a long time, but actually provided you’re not overweight, you’re fit and healthy and you don’t smoke, you can actually take the pill all the way up to the menopause.

Can you be too young or too old to be on the Pill?

As you get older, some of the health risks with the Pill get relatively larger. For example when you’re very young the risk of getting breast cancer is very small – as you get older, that relative risk increases, so the potential dangers of taking the Pill increase with that. Most family planning practitioners and doctors would think carefully about putting a woman over 35 on the Pill, because the oestrogen does have side effects that increase risk, so they might think of either switching to a pill that doesn’t contain oestrogen or some other form of contraception. That’s particularly if they smoke as well or have put on a bit of weight, which are other risk factors for heart disease so that could be a problem.

Are all Pills free on the NHS or do you have to pay for some?

All Pills are free on the NHS; it’s one of the totally free services that the NHS provides.

Just how effective is the Pill as a contraceptive?

It’s 99% effective at preventing pregnancy. It’s as good as you can get – that’s if you take it properly. With the Pill you do have to remember to keep taking it and its better if you take it at the same time every day. So when people talk about the Pill failing, usually they have missed a few pills or there has been an illness [antibiotics, vomiting and diarrhoea for example may reduce the Pill’s effectiveness].

Would you recommend using other contraception with the Pill?

If there are times when you have missed Pills, then the advice may be to use condoms as well until your contraceptive cover comes back to its proper level, but also bear in mind, the Pill won’t protect you from sexually transmitted infections, so if you’re having different partners then it’s always a good idea to use condoms as well as taking the Pill. And of course there are other forms of contraception besides the Pill, so if you’re somebody who’s just not very good at remembering to take pills perhaps it’s not the contraceptive for you.

If you miss a Pill what are the chances of getting pregnant really?

It depends on the Pill you’re on, how many pills you miss, and where about you are in your packet when you miss your Pill, so it’s quite complicated and it’s worth getting some good advice – there are some great leaflets you can keep in your drawer that family planning produce, that tell you exactly what to do in the event of missing a Pill.