The role of weight in fertility health is complex. While weight does not always play a role in fertility problems, it is a hurdle for some couples trying to conceive. Evidence shows that obesity is a primary cause of female fertility problems in about 6% of cases. Another 6% of female infertility cases are caused from being underweight. There is good news: Research shows that correcting a weight challenge that triggers infertility can lead to natural conception in up to 70% of women!
How Does Weight Affect Fertility?
Being overweight or underweight affects natural fertility, medical fertility treatments, and pregnancy in various ways.
1. Being underweight or overweight can affect ovulation. Without ovulation, there is no chance for conception. Women who are underweight may experience anovulation and stop getting their menstrual cycle. We see this in women who over train/exercise, experience drastic weight loss or have eating disorders. Yet, some women face this problem, even if they are only slightly underweight. Having adequate body fat is critical for fertility. If your body fat is too low (below a BMI of 18.5), it can prevent the release of an egg or ovulation each month. Some experts suggest body mass index should be around 22 for optimum fertility.
Being overweight can also wreak havoc on ovulation. Overweight women often have higher insulin levels, which cause the ovaries to produce more androgens (male hormones), preventing normal egg release or ovulation. Insulin-resistant PCOS is a common cause of anovulation, female fertility problems, and is, in part, tied to weight challenges.
2. Weight challenges decrease male fertility. For men, being overweight or underweight can lead to lower testosterone levels and reduced fertility. Low testosterone levels decrease the testes’ ability to produce healthy sperm. Excess body weight can increase estrogen levels, and the number of abnormal sperm – a risk factor for miscarriage or chromosomal problems in a pregnancy.
3. Weight challenges can impact the success of IVF treatments. Being overweight or underweight can affect the body’s responsiveness to fertility medications. Further, the egg retrieval process is sometimes more difficult in women with weight challenges. Women with these issues are also more at risk for having immature eggs and a lower success rate for embryo transfer. Early research suggests having a high BMI can even reduce your IVF success rates if you’re using donor eggs.
4. Weight challenges can lead to pregnancy complications. Being overweight or underweight presents special challenges in pregnancy. Being overweight can increase the risk of miscarriage, high blood pressure, gestational diabetes, premature birth, preeclampsia, and delivery complications. Being underweight during pregnancy can lead to low birth weights or preterm delivery. It’s important to do your best to address a weight challenge prior to conception whenever possible.
Are you unsure if you’re at a healthy weight?
You can use a standard BMI calculator to find out your body fat based on your weight and height. Do your best to stay within a normal range (18.5–24.9). Studies suggest a BMI below 30 is best for fertility health. If you’re outside of the normal range, ask yourself what your weight blocks are. Sometimes, emotional issues are behind troubles with weight and food. Stress, anxiety and depression are other common weight challenge triggers.
Healthy Weight Solutions
1. Take a look at your diet composition. You may not be eating enough or you may be basing your diet on the wrong kinds of foods. Many clients I work with addressing fertility concerns are not eating regular, balanced meals. Skipping meals is a common problem I see for both underweight and overweight clients.
- The Fertility Diet is a building diet. Each meal should consist of colorful vegetables or fruit (covering half your plate), a healthy protein and a healthy fat. For excess weight or PCOS, it makes a huge difference to balance your daily protein intake with an equal or lesser amount of complex carbohydrates.
- Healthy, complex carbohydrates are an important source of nutrients for your diet. Simple and processed carbohydrates (refined bread, potatoes, pasta, white rice, high sugar foods) do not offer much nutritionally and are culprits for hormone imbalance. Having a treat once in awhile is okay. For your regular diet, choose carbohydrates from whole grains, fruits and vegetables, legumes, and beans instead.
- If you struggle with eating enough food or have a history of an eating disorder, focus on nutrient-dense foods. If you can’t seem to clean your plate, enjoy a smaller meal along with a Fertility Smoothie with added whey or plant protein. Add more essential fats to each meal, such as avocado, raw nuts and seeds, or nut butters. Include a booster like spirulina for added nutrition in your daily drinks. Work with a counselor experienced with eating disorders if you need more support.
2. Get your body moving. Strive for low-impact exercises at a moderate intensity level, like walking, light jogging, swimming or Fertility Yoga, 30-60 minutes, 5 days a week. Enlist the support of a personal trainer who can help you create a program for your preconception needs, or consider a preconception fitness and wellness program like Fit & Fabulous. Avoid over training or intense exercise programs as they can increase testosterone levels or lead to further weight loss for underweight people.
Healthy Weight Round up
If you have a weight challenge that is affecting your fertility, start with small steps to improve your diet and lifestyle. Here too are 10 Steps to Sustained Weight Loss & Achieving a Healthy Weight. Extremely rigid programs are usually unsustainable and may lead to other deficiencies or imbalances. Keep a daily food and exercise journal to stay accountable.
Ask for support as you go through this process. Especially take advantage of natural stress relief therapies. Reduce your stress with mind-body therapies to ease the emotional component of a weight challenge. Be easy on yourself! Know that the changes you’re making could be the key to renewed fertility and a healthy pregnancy in the future.
- Green, B. B., Weiss, N. S., & Daling, J. R. (1988). Risk of ovulatory infertility in relation to body weight**Supported in part by the National Institute of Child Health and Development, contract NOI HD 02821. Fertility and Sterility, 50(5), 721-726. doi:10.1016/s0015-0282(16)60305-9. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0015028216603059?via%3Dihub
- Malik, S. (2014, Nov.). The Truth about Weight and Fertility. Retrieved from: https://www.shadygrovefertility.com/blog/fertility-health/the-truth-about-weight-and-fertility/
- Fertility and A Woman’s Weight. (2017). Retrieved from: http://yourfertility.org.au/for-women/weight-and-fertility/
- Barton, D. (2017). Study Shows Increased Infertility Risk for a BMI Over 30. Retrieved from: http://natural-fertility-info.com/overweight-infertility.html
- Rodriguez, H. (2017). Infertility Due to Being Underweight. Retrieved from: http://natural-fertility-info.com/infertility-due-to-being-underweight.html
- Redmond, J. (2017). How Fat Can Affect Fertility. Retrieved from: https://www.fertilityauthority.com/articles/how-fat-can-affect-fertility
- Aquilina, J. (2017). Will Being Underweight Affect My Ability To Get Pregnant? Retrieved from: https://www.babycentre.co.uk/x554802/will-being-underweight-affect-my-ability-to-get-pregnant#ixzz4lVzNCmAu
Sarah has worked in the field of natural foods and herbalism for over 20 years. She’s the Co-Author of “Healthy Healing” with over 1 million copies sold, a Certified Herbalist, and a health and wellness consultant. Sarah Graduated from the Professional Herbal Studies program at East West School of Herbology, and holds a Bachelor’s Degree in English from St. Mary’s College. Working with women on their journey to wellness is her passion and she loves to share what she has been blessed to learn from naturopaths and other herbalists over the years.
