Weight and Fertility

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A woman’s weight can affect her fertility. There is evidence that the amount of fat stored in a woman’s body can be correlated with the production and distribution of estrogen. Women who are overweight, obese, or even too thin may experience irregular or infrequent menstrual cycles. Anovulation can occur.

To find out if your weight may be a cause of your infertility, we recommend using the Body Mass Index (BMI). A BMI is a statistical measurement which compares a person's weight and height. Though it does not actually measure the percentage of body fat, it is a useful tool to estimate a healthy body weight based on how tall a person is.

BMI Guidelines:

• A BMI of 19-25 is considered normal or healthy
• A BMI < 19 is considered underweight
• A BMI 26-29 is considered overweight, but not obese
• A BMI over 30 is considered obese

BMI = weight (in kilos) divided by height (in meters) squared

• To convert from pounds to kilos, take pounds divided by 2.2
• To convert from inches to meters, take inches times 0.0254

To calculate your BMI, visit the National Institute of Health at: http://www.nhlbisupport.com/bmi/

To view a BMI Index Table, visit http://www.nhlbi.nih.gov/guidelines/obesity/bmi_tbl.pdf

Why weight Matters?

While many physicians and health care providers find it difficult to talk to their patients about infertility and weight issues, it is important to understand that obesity does play a significant role in fertility success. While the general consensus is that a BMI >30 has a significantly negative effect on fertility treatment success rates, some studies have shown a 50% decrease in clinical and ongoing pregnancy rates in women undergoing in-vitro fertilization (IVF) with BMI>25 when compared to those with BMI≤25. A high BMI can cause decreased efficacy of fertility medications, safety concerns and increased complication risk during surgical procedures such as egg retrieval, and serious complications during pregnancy and delivery.

At Advanced Fertility Care, our patients’ health and well-being is our first concern, therefore, prior to undergoing any assisted reproductive procedure (IVF or donor egg IVF) we will insist that our patients achieve a BMI≤32 in order to maximize your chance of success and minimize any health risks.

If you have a high BMI and are struggling with infertility, we strongly encourage you to enter a weight loss program. Weight loss of 5% to 10% may dramatically improve ovulation and pregnancy rates. Weight loss of even 15 pounds has been shown to restore ovulation in women who are anovulatory and over weight.

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