This week a new study will reveal how much ignorance surrounds contraception in Britain. Here Lucy Fairford tells how, after suffering years of mood swings, she found the pill might be to blame

It was labelled 'Blue Monday' - the most miserable day of the year, according to psychologists - when bad weather, Christmas debt and broken resolutions combine to spread a collective despair. Yet on 22 January I was feeling unusually happy.

My 'high' had lasted two weeks and was affecting every part of my life. I was having more fun with friends, loving work and my relationship with Amit was stronger than ever. Weirdly, my change in mood came the day I stopped taking the contraceptive pill.

Could it be that for more than two years I had been taking a tablet day after day that had left me subdued, out of sorts and feeling odd without me even noticing it? Or was it all in my head?

I asked my boyfriend whether he thought the two might be linked but he was not convinced. He pointed out that I had not appeared unhappy for the past two years and the way I was feeling now was probably temporary. If this pill that I had been taking had any side-effects, he added, they were tiny compared with my last experience. That was certainly true.

I first started taking a combined oral contraceptive, which contains oestrogen and a progestin, three years ago when I was prescribed an older style of pill, known as 'second generation'. Although lots of my friends took the same brand and felt fine, I felt as if I was going crazy.

I went from being a fairly rational person to someone whose emotions spiralled out of control. Anything could set me off. I cried at TV adverts, talk shows and soap operas. I broke down in front of friends. I got moody, lost my temper quickly and started screaming rows with Amit. In the end, my unpredictable moods contributed to the breakdown of our relationship.

However, when I came off it I felt like a mist had lifted. Amit and I got back together, I started a newer 'third generation' brand two years ago, and noticed nothing more until last month. Now I am asking again, did the pill play with my emotions?

It is a difficult question. Despite the fact that it is one of the most researched drugs in the world, it is extremely hard to carry out robust studies around how the pill affects mood.

Anne Szarewski, a specialist in family planning at the Margaret Pyke Centre in London, said there was evidence the wrong type of pill could have a terrible effect: 'On the worst level someone who was reasonably happy suddenly has acne or gets depressed. It can affect everything you do, you can lose confidence in work or in a relationship and that has a piling-up effect.' But 'very few' women who tried hard enough, sometimes trying four or five different types of pill, would not find one to suit them. Maybe I had simply not tried hard enough.

What is clear is that many women, including myself, make far too little effort to educate themselves. When I decided to write this article I called experts and was amazed by how ill-informed I was.

I knew barely anything about most of the 30 brands of pill on offer and I was dismally unaware of other long-lasting methods of contraception. Tomorrow new research will be released to show that I am far from alone. A study by the Family Planning Association will expose the extent of misunderstanding around sex and reproduction. That report, carried out to launch Contraceptive Awareness Week, will show how little women know about alternatives to the pill and how little they research them.

Toni Belfield, director of information at the FPA, said women would spend days choosing a new outfit, but not picking contraception. I have to admit I spent longer last week researching which food processor I was going to buy than I have ever spent finding out about the pill. The reason I came off it last month had nothing to do with my emotions but because my sex drive had fallen. It was only afterwards that I noticed my mood had lifted. I emailed my friend Catherine, who had been taking the same brand, and was shocked by her response. She wrote: 'I lost my sex drive and after looking on the internet wondered if it could be the pill. I stopped taking it last month too, and I've been so much happier. I've been trying to decide whether it's just that I have been getting on better with my boyfriend, or if it could be the pill.'

There are many other reasons why Catherine could be feeling better. Last year she faced the stressful job of moving abroad and settling into a new city. But, like me, she has a gut feeling that coming off the pill made her feel better.

One night I mentioned it to a friend, Seema. 'The first time I went on the pill I felt like I had PMT all the time,' she said. 'I was not in control of my emotions, I was really irrational.' She came off it and immediately returned to 'normal'.

A year later she went back to her doctor to try again, explaining what happened the first time. 'He laughed and told me his girlfriend had taken the same brand and turned into a monster,' she said. He prescribed something new and she has felt fine ever since. Seema had switched from a 'second-generation' to a 'third-generation' pill.

Szarewski said she was completely convinced that these newer pills carried fewer side-effects than older ones but added that doctors were under pressure to go for cheaper, older options.

Martyn Walling, a GP in Boston, Lincolnshire, with a special interest in contraception, said it was common with some brands to hear women say they didn't realise until they came off the pill just how bad they felt. One third of women who start the pill will stop within a year, he said, often blaming side-effects such as mood swings or acne.

What about other options? I believed that what I termed the 'coil' was not for me as I had not had children. Yet, the intrauterine device and intrauterine system are both options I could have gone for. So were the implant and the patch. There is no evidence that any of these methods carry the risk of mood swings yet I knew nothing about them.

Research by the FPA has shown that 76 per cent of women had never heard of the intrauterine system, 24 per cent of the implant and 12 per cent of the injection, all long-acting methods of contraception. Meanwhile, only 32 per cent of callers to their helpline said their doctor or nurse had talked about these methods.

Of course, condoms are also an option but as I am in a long-term relationship and we have both had tests for sexually transmitted diseases we would prefer to find another option. Finding the right pill has its advantages too. I am already dreading the fact that I have no idea when my period is due or whether it will be as painful or heavy as it was before the pill. My skin has also deteriorated as my mood has improved.

'What all this illustrates is that we as women have individual and very different tendencies to different things in life,' said Belfield from the FPA. 'When you take a hormone you need to think about not exacerbating something that there is already a tendency towards.'

But for the majority, Belfield added, the pill did not carry such side-effects. 'Three and a half million women in the UK are using the pill. Women do vote with their feet.'

The risk of an unwanted pregnancy, she added, could be much worse. One friend, Gemma, came off the pill last January and two weeks later fell pregnant after a one-night stand when she was not using a condom. The result was devastating. 'When I found out, I was five weeks pregnant with twins,' she said. 'I am an assertive, confident woman and know my rights but the experience was atrocious. I was passed from pillar to post by doctors who were all "nice" but failed to help. I felt it took away from the main issue: did I want to keep the child?'

Gemma had an abortion when she was 10 weeks pregnant. 'I had been an absolute mess when I was making the decision. A few hours after it happened I was sobbing and could not move. It was the most incredible sadness I had ever felt.' By the end of last year Gemma's depression was so bad she was unable to leave her flat except for work and last week she started counselling. 'I now see the consequences of unsafe sex,' she said.

Despite admitting he would be reluctant to take the 'male pill' that could be on the market within eight years, my boyfriend thinks I blame the pill too much. I think there is an element of truth to that. When I put weight on a few years ago, it was probably the fact that I was eating too much and doing no exercise but I blamed the pill. When I lost my sex drive it may have been because I was feeling stressed and tired but, again, I blamed the pill.

However, there are other times when I really do believe the pill affected my emotions. If it did not create the tension in my relationship, it certainly whipped it up and left me less able to cope with what was happening.

Many of my friends are young, professional women who are sexually active in long-term relationships. Finding contraception that suits them is crucial. I don't want to put women off the pill, I simply want to highlight that people like myself, Seema and Catherine are not alone. Feeling as though your emotions are in turmoil can be scary and it is awful to look back and see just how irrationally you behaved. Equally, I know I will be able to find an option that works for me. After all, taking a risk is not an option.

A popular revolution

The pill was developed by American biologist Dr Gregory Pincus. Tested in the 1950s on Puerto Rican and Haitian women, it came to the UK in 1961 for married women only.

· Ovulation is suppressed, so there is no egg for fertilisation by sperm, by the actions of the hormones (oestrogen, or a mix of oestrogen and progestin) in the pill.

· Health fears centred on hormone levels in the pill; many have now been lowered. Originally the pill had about 50 micrograms of oestrogen and it now contains around 30. Progestin levels have been cut to a tenth of their original level.

· Today 3.5 million women in the UK, around one in four of those aged 16 to 49, take the pill.

· The last UK scare was in 1995 when 'third generation' pills were linked to thrombosis. Many gave up the pill, abortions and pregnancies rose. The Family Planning Association called it a 'blip'.

· In 1999, in her book The Whole Woman, Germaine Greer, left, wrote that 'contraception is abortion'. Newer pills did not stop a woman conceiving, she argued, and it was a 'cynical deception of millions of women' to sell them as contraceptives rather than abortifacients. 'What women don't know does hurt them,' she said.