As a therapist specializing in women’s issues, I have regularly witnessed the struggles that many women and girls have with weight. After all, rare is the woman who has not felt the effects of our society’s obsession with thinness, on the one hand; and with food, on the other. I dare you to watch a television show that targets females or read a women’s magazine without finding ads for rich foods and recipes, interspersed with messages that we can, and should, achieve physical perfection – whose cornerstone is a standard of thinness most of us cannot attain.

For many, those mixed messages create contradictory attitudes and behaviors about body size and diet. We are tempted to eat, eat, eat; while we obsess about being thinner, thinner, thinner. As a result, some of us battle being overweight or underweight while others become caught in a vicious cycle of losing weight and gaining it back. Those fights are painful. They affect our body image and self esteem.  And, as many women who decide to get pregnant find out – sometimes too late – they affect our fertility.

Body fat plays a critical role in human reproduction and either too much or too little of it can lead to infertility.  According to the American Society of Reproductive Medicine (ASRM),  the recommended Body Mass Index (BMI) range for women who are trying to conceive is between 18.5 and 25. A BMI over 25 is considered “overweight” and anything beyond 30 is considered “obese”. On the other end of the spectrum, a BMI under 18.5 is considered “underweight”.

Women who are overweight or obese have less chance of getting pregnant overall. One reason is an imbalance of the hormone estrogen, which is produced by fat cells. Women with more fat cells tend to have higher levels of estrogen. Higher levels of estrogen can prevent normal ovulation, in essence acting as a form of birth control which prevents conception.  Even overweight women with regular cycles and otherwise no obvious fertility problems may have a hard time getting pregnant, taking longer (frequently more than a year) to conceive, compared to women of healthy weight.

Being underweight also can reduce a woman’s fertility. It too, can result in insufficient production of key hormones, leading to anovulation (a lack of ovulation), irregular ovulation, and irregular menstrual cycles. So even a young woman with plenty of healthy eggs may not be able to get pregnant if she is too thin.  And for women going through infertility treatment, being too skinny may actually be worse than being too fat.  A recent study found that underweight women going through in-vitro fertilization (IVF) were less likely to become pregnant than those who were overweight – including those classified as dangerously obese.

The good news is that, for many people, adjusting their weight toward the “healthy” BMI range often restores normal hormonal balance. More than 70% of women who are infertile as the result of being over- or under-weight will conceive without medical intervention if they gain or lose weight, as appropriate.

So what can you do?  Whether you are trying to get pregnant right now or you are looking at building your family in the more distant future, it is helpful for you to establish a healthy weight before subjecting yourself to expensive, time consuming infertility treatments. Consider working with a therapist who specializes in fertility, eating issues, or both to create a healthy relationship with food and your body. If you use food and exercise in a way that may affect your fertility, a therapist can help you stabilize your behavior and your body in order to optimize your fertility health and put you on the path toward an easy and healthy pregnancy. Good luck!

To learn more about fertility health, join me on August 20 for “Sip, Shop, & Shine” –  a night of pampering, shopping, and honest conversation about fertility and women’s health!