Young woman standing on a scaleWhen it comes to fertility, your BMI (body mass index) means more than you might have originally thought. Conception is a challenge for people of all body types, but especially for those whose BMI range has reached 25 percent or higher.

For those of you who aren’t familiar with the term, your BMI is a measure of your body fat percentage that takes into account your height and weight. If you have 22 percent BMI, that means that 22 percent of your body’s weight is composed of fat.

So why is your BMI affecting your fertility? The answer is different depending on your gender:

  • Women in the healthy range have more regular ovulation of a healthy egg. Body fat releases estrogen. When there is too much body fat, there is often too much estrogen in a woman’s system. As a result, her delicate balance of hormones can be off and results in irregular ovulation or ovulation of an egg that isn’t at its best. Sometimes, it can result in the ovulation of no egg at all.
  • Men in the healthy range tend to have better sperm health. Many studies have confirmed that most men in the healthy range of BMI have better sperm samples than those in the higher or lower ranges. Male fertility is measured based on the sperm count, movement (motility) and shape (morphology). Men’s samples in studies have shown better readings over and over again in all categories.

Being underweight is bad for fertility as well. The healthiest BMI range is 18.5 to 25 percent. Anything below that is too little body fat and anything over that is too much. Many times, in the case where the patient is underweight, I recommend that they try to add more calories to help boost their body fat content. If the patient has little body fat because they are participating in extreme training, most experts agree that laying off the intensity is a great way to let their body’s reproductive system be at its best. Active is great, but too much of a good thing can be bad for fertility health.

Bringing down your BMI percentage isn’t complicated. It requires discipline and change to your current lifestyle in most cases, however. The idea is to burn more calories than you eat. You can achieve this by eating nutrient-dense foods that are lower in calories and by boosting your physical activity levels. In addition, adding in weight training is a great way to build more muscle, which replaces fat and lowers your BMI.

When it comes to lowering BMI, I recommend the following steps:

  • Eat more whole foods. Replace processed foods with their whole food counterparts. Not only will you get more nutrients, but you will also avoid some chemicals and additives that could have detrimental effects on your fertility health.
  • Get at least 30 minutes of cardiovascular activity a day. This can be a low-impact activity like a daily walk or a high-intensity crossfit class. It’s your choice, but be sure to choose something you enjoy. Then, you have a much better chance of sticking to it.
  • Rethink your protein options. When you are looking at reducing your caloric and fat intake, cut back on red meat and look for lean sources of protein, including chicken and turkey breast, as well as beans and other legumes.

Having a healthy BMI is important when you are trying to facilitate conception. Being in the 18.5 to 25 percent BMI range is critical, whether you are a man who wants to boost his male fertility or a woman who wants more predictable ovulation of a healthy egg. Making sure that you get in the healthy range is one of the best things you can do to optimize your fertility.


Chavarro, M.D., Jorge E. “How Diet Affects Fertility.” 26 September 2011. Web. 8 August 2014. <>

Bouchez, Colette. “Getting Pregnant: Easy Ways to Encourage Fertility.” Web. 8 August 2014.