The Nurses’ Health Study found that weighing too much or too little can interrupt normal menstrual cycles and throw off ovulation or stop it altogether.

There is a wide range of body shapes and sizes that can be healthy and the number on the scale is not that relevant as a measure of health. Body Mass Index (BMI) and waist circumference are two measurements that when used together can better help to assess for a healthy weight.

The Body Mass Index (BMI) Chart is the same for males and females. It is simple to use. First find your height on the chart. Then find your weight on the chart. The number where they cross is your body mass index (BMI). A healthy BMI of 20 to 24 is considered the fertility zone. Women with a BMI less than 20 may be at an increased risk of infertility. If you are too lean, gaining five or 10 pounds can sometimes be enough to restart ovulation and menstrual periods Adults with a BMI above 25 may be at an increased risk for metabolic syndrome, type 2 diabetes and polycystic ovary disease. Overweight also reduces the chances that in vitro fertilization or other reproductive technologies will succeed while increasing the risk of miscarriage, high blood pressure (pre-eclampsia), gestational diabetes and the chance of needing a Cesarean section. If you are overweight, losing 5 percent to 10 percent of your current weight is often enough to improve ovulation.

This number alone isn’t the whole picture. Some people with high muscle mass will appear to have a higher BMI. However, when used along with waist circumference measurements, it does give a more comprehensive picture of your weight status. .

Waist circumference is a measure of the health risk associated with too much stomach fat.  Men with a waist circumference more than 102 cm (40 in) and women with a waist circumference more than 88 cm (35 in) are at increased risk of developing weight related health problem.
To measure your waist circumference, place the tape measure half way between your hip bone and your lowest rib.  This will be about 5 cm (2 in) above your belly button.  Wrap the tape measure around you in a circle.  Make sure the tape measure is level all the way around. The tape measure should not push in or indent the skin.  Relax, exhale and measure.

A small change in weight can make a difference. Even a change of 10% has been found to have a positive effect on health. See weight management area for support with weight loss or weight gain.

Measuring BMI and Waist Circumference
BMI is a ratio of weight to height. It is calculated by dividing your weight in kilograms by your height squared (in centimetres). Or use the BMI nomogram at http://www.hc-sc.gc.ca/fn-an/nutrition/weights-poids/guide-ld-adult/bmi_....
To measure your WC, place the tape measure half way between your hip bone and your lowest rib.  This will be about 5 cm (2 in) above your belly button.  Wrap the tape measure around you in a circle.  Make sure the tape measure is level all the way around. The tape measure should not push in or indent the skin.  Relax, exhale and measure.

Fertility Diet Recommendations:

A small change in weight can make a difference. Even a change of 10% has been found to have a positive effect on health. See weight management area for support with weight loss or weight gain.