Infertility often caused by women being either too thin or overweight

Infertility often caused by women being either too thin or overweight

As my GP fiddled with some papers, I guessed he had bad news. Nervously he blurted out: ‘I’m afraid that you will never have children naturally.’ I felt as if I’d been punched. Walking out of the surgery, all I could focus on were chubby-cheeked babies in the arms of beaming mums. I realised I might never hold my own child, and my tears started.

My doctor’s gloomy prognosis was not down to me having blocked fallopian tubes, leaving it too late (I was 32) or low-quality eggs. The problem was I had been too thin. From the age of 24 until I hit 30, I was anorexic. During this time, my weight hovered at 6st and at times dropped lower still, nowhere near enough for my 5ft 3in frame.

Some of the effects of my condition were obvious. I had problems sleeping, often felt faint and had thinning hair. But what I did not consider was the harm being done to my chances of becoming a mother. Last week, Chantelle Houghton, who found fame on Celebrity Big Brother, revealed she has been left infertile at the age of 27 as a result of extreme dieting.

‘Because of my obsession with food and crash dieting when I had bulimia, I’ve ruined my chance of having a baby naturally,’ she told a magazine. ‘All the time I was making myself sick I was thinking: “Yes, I’m getting skinnier” — but it’s cost me the chance of having a family.’ There are 1.6 million people in Britain with an eating disorder, the most common being bulimia, when the person binge eats and purges food through vomiting or laxatives. Bulimics, however, will not necessarily be underweight. Those with anorexia will have a body mass index (BMI) of 17.5 or less, restrict their food and drink intake and tend to over-exercise.

Yet it’s not just anorexics who are putting their fertility at risk. Any extreme dieting can limit the chances of having a family — and so, as we should see, can overeating. The normal warning sign that a woman’s fertility is being affected is when her periods stop. Mine stopped when I was 26, when I weighed over 6st. ‘The hypothalamus in the brain controls the release of hormones from the pituitary gland that drives the menstrual cycle, stimulating the ovaries to produce eggs,’ says Dr Marie Wren, deputy medical director of the Lister Fertility clinic in London. ‘But if a woman loses a lot of weight, this process shuts down. It’s the body’s way of preserving what resources it has. If a woman menstruates, she loses iron — and if she has little nutritional input, she can’t afford to lose that.’ Bulimia and faddy yo-yo dieting can also trigger this process.

‘If your body weight is yo-yoing, then it is possible your body would perceive this as a stress and so switch off the ovulation mechanism,’ says Amanda Tozer, consultant in reproductive medicine at Barts and the London Hospital. ‘If you are just losing a few pounds either way you’ll probably be fine, but if your weight is really going from one extreme to another than this may happen.’ Following low-calorie restrictive diets may also compromise a woman’s chance of getting pregnant. ‘If you aren’t getting enough nutrients, then your body will not function as normal and this will reduce fertility,’ says Dr Wren. Sadly, the effects can be lifelong. About 20 per cent of those who become seriously underweight find their menstrual cycle never returns, even when they are a healthy weight.

‘I have a number of anorexic patients who are now at a normal body weight, but the firing system from the hypothalamus in the brain is not yet working again properly,’ says Dr Wren. ‘Often, the only way they can conceive is if we try to kick-start the ovulation process with drugs.’ Gauging fertility is not an exact science. There is no set BMI at which fertility is guaranteed. ‘The threshold varies from person to person,’ says Miss Tozer. ‘The NHS does not give fertility treatment to anyone who has a BMI under 18 as this is felt to be the minimum weight at which a woman would have a healthy baby. But I have known naturally slight women who conceive naturally, even with a BMI under 18.’

Fertility treatment is also not available on the NHS to those with a BMI over 30 — because being overweight affects your chances of having a baby almost as much as being underweight, as secondary school teacher Charlotte Ball, 30, discovered. Having gained weight steadily throughout her life, by 2009 at the age of 28 she weighed more than 18st with a BMI well over 30. ‘At that time, my husband Greg and I were starting to think the time was right to start a family,’ says Charlotte, from Sunderland. ‘I asked my doctor what I could do to help ensure I had a healthy pregnancy. He said I would have significant difficulty at that weight because if affects the hormonal balance of my body. ‘It was a real wake-up call. I was having regular periods and thought I would just get pregnant.’

Charlotte started the LighterLife diet in September 2009, and by May 2010 weighed 10 st with a BMI of 24.5. She lost seven more pounds and her daughter Matilda was born in May this year weighing a healthy 8lb 2oz. ‘Women who are overweight are more likely to have Polycystic Ovary Syndrome (where the ovaries develop cysts) which reduces their chance of conception,’ says Miss Tozer. ‘They also have an increased risk of developing diabetes, of having a premature birth, of having a stillbirth and of having an overly large baby, which can lead to a complicated delivery.’ Dr Wren adds: ‘It is not just a woman’s fertility that is affected by weight. An underweight man will have poorer quality sperm as he is undernourished. Likewise, if he is overweight. One study found that men with a high BMI ejaculate less sperm and more of them are abnormally shaped than normal.’

Fat cells are thought to release oestrogen, which affects sperm count and quality. Sadly, few of those counting calories — or comfort-eating — consider how their actions may harm their chances of having a family. When anorexia took hold of me at age 24, children were the last thing on my mind. Each day I’d have a mouthful of cereal, go to work, walk home and do a fitness video after a meal of boiled veg. Before this I was a bit tubby (weighing more than 9 st) but had always thought myself well-balanced and happy. But I didn’t have much self-esteem and some bad relationships sent me over the edge.

I was initially in denial about my condition, putting it down to the stress of my demanding job in TV. But, in 1998, when my weight dropped to 5½ st and I became too weak to walk, I admitted I could not battle the condition alone, and sought the help of a counsellor. By 2002, aged 32, I had been at a stable weight of more than 7 st for more than two years but my periods still had not returned. By now in a happy relationship with my husband-to-be, my desire for a family was increasing all the time. It was not until June 2003, aged 33 and 7½st that my periods returned. By then I was married and my husband and I continued trying for a family for six months.

Then came that depressing day my GP told me I would not conceive without help. He referred us for IVF. However, I pulled out, fearing nature was preventing me from conceiving as I would pass on my anorexic tendencies to a child. I can’t pretend I was easy with our decision. After cuddling my friends’ kids, I would go home for a weep. Then, in February 2004, against all the odds, I became pregnant. It was the most wonderful shock. Any thoughts of dieting disappeared that day. I ate what I wanted and have done pretty much ever since. In October 2004, our son Louis was born. My husband and I started trying for another child almost instantly after Louis, but even though I then weighed (and still do) 8½ st — it hasn’t happened. When people say to me: ‘So you just have the one child then,’ I feel myself bristle. Yes I do — but what a miracle it is I even have him.

Article: 26th July 2011 Read more about IVF and fertility at

Posted: 26/07/2011 12:03:06


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