When struggling to achieve pregnancy, there are a number of questions that often come into the mind. One of the questions we’ve heard many times is in reference to weight and infertility, and whether or not they are related. The answer to this is a little more complicated than a simple yes or no. However, in this post we’ll explore the subject in depth to give you some insight, and hopefully answer many of the other questions surrounding this complex issue.

Weight and Infertility - What’s the Connection?

Although it is not be a direct one, there is a connection to weight and infertility. However, it’s important to note that there is no guarantee that being a certain weight will ensure the ability to achieve pregnancy. On the other hand, we do know for a fact that your weight, diet and lifestyle choices can have an impact on your body and its ability to function properly. For example, exercise and diet can affect your menstrual cycle. We know that a woman must be menstruating to conceive. Therefore, if something she is doing is preventing or disrupting menstruation, she will have a harder time getting pregnant.

How Does Exercise Affect the Menstrual Cycle?

You might be wondering how exercise is related to weight and fertility. The relation lies in the fact that many people work out to lose weight, or to maintain their current weight. The trouble arises when you work out in excess. According to some experts, irregular menstruation in a woman may be an indication that she has been exercising too much. Engaging in frequent and intense workouts, without the support of a good diet, can not only cause menstrual changes, but can also lead to bone fractures and other problems that negatively impact your overall health. Regardless of activity level, as a woman exercises, she expels a significant amount of energy. As the difficulty and duration of the workout increases, so does the amount of energy being used. If you're not consuming an adequate amount of food while expelling this much energy, your body essentially goes into a starvation mode which can lead to the reproductive system shutting itself down. The reproductive system isn’t considered a vital system for survival by the body, and this starvation mode is can cause you to stop ovulating and stop having periods as a result. Sometimes it's not a matter of your body going into starvation mode, though. For some women who exercise too frequently and/or too intensely, their bodies release stress hormones that disrupt an otherwise normal menstrual cycle. When cortisol and epinephrine rise, it can restrict blood flow to the uterus affection conception. The impact of stress hormones on the reproductive organs are one of the reasons that there is a misconception that women just need to calm down to get pregnant. Unfortunately, like many things related to fertility, telling someone to calm down is too simplistic for what may be a more complex problem.

How frequently should a woman be working out, and at what level of intensity?

According to the Centers for Disease Control and Prevention (CDC), “Adults need at least 2 hours and 30 minutes (150 minutes) of moderate intensity aerobic activity (i.e., brisk walking) every week, and muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders, and arms).” OR “1 hour and 15 minutes (75 minutes) of vigorous-intensity aerobic activity (i.e., jogging or running) every week and muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders, and arms).” OR “An equivalent mix of moderate- and vigorous-intensity aerobic activity and muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders, and arms).” If you are working out more than this, you may be working out too much, and as a result affecting your menstruation cycle. The exception however, is if you're consuming more calories than you're burning while exercising your cycle might not be affected. Then again, the foods and beverages you are consuming can also have an impact on your menstruation cycle.

Diet and Its Relation to Weight and Infertility

What you eat, and how much you eat can have a significant impact on your body, and its systems - including your reproductive systems. The amount of sugar you consume, the vitamins in your foods, and even your caloric intake can all be factors in the regularity of your monthly cycle. One element in your diet that can change your cycle is your sugar consumption. For example, a high intake of sugar increases the blood sugar levels of an individual, which may lead to very heavy periods and severe cramping. These heavy periods can also cause other health issues. When there is an increase in your insulin levels, you may also suffer from ovulatory disorders. Some women begin to produce too many male hormones due to these high insulin levels, and stop releasing eggs. For others they might be menstruating, but aren’t ovulating. You also need to have enough fat in your diet. Now, this one might sound strange in an article about weight and infertility, because many would assume that low fat is best for a healthy diet. The truth is if your diet is too low in fat, you might not be able to have a menstruation cycle. For some women, when they continue a low fat and/or low carb diet for too long, they suffer from Amenorrhea - a condition where a woman's menstrual cycle being absent for 3 months or more. Others simply have irregular cycles which can disrupt their chances of ovulation. If you have a high-volume of alcoholic beverages in your diet, this can disrupt normal menstrual cycle length as well, according to the National Library of Medicine, National Institutes of Health. Consuming copious amounts of alcohol can also cause a woman to gain weight significantly, which can lead to other issues both related and unrelated to fertility.

What foods should you be consuming?

Some people wonder if there is a special diet they can go on that will help them with their weight and infertility issues. While there is no miracle diet that will ensure you get to your goal weight, or that you will get pregnant, there are some things to keep in mind for achieving better health overall. In terms of what you consume, balance is key. Choosemyplate.gov recommends a diet of “fruits, vegetables, whole grains, and fat-free or low-fat dairy products…” They also recommend you “include protein foods such as poultry, fish, beans, eggs, nuts and lean meats.” You should also “choose foods that are low in saturated fats, sodium, and added sugars.” Hydration of the body is also critical for optimal health, and consuming plenty of water may aid you in achieving or maintaining a healthy weight. Drinking lots of water can help you feel fuller longer, and can flush your body of toxins that may assist in resetting some of your systems such as your reproductive systems. Be careful not to drink your calories. Water is the best beverage you can reach for. One of the easiest ways to gain weight or derail your diet, is by mindlessly grabbing calorie laden beverages such as sodas, juices, and alcoholic beverages.

Weight and Infertility By The Numbers

What is the ideal weight for a woman who is trying to get pregnant? The CDC, defines a person with a body mass index (BMI) of less than 18.5 as underweight. The normal range, or a person who is considered of healthy weight, has a BMI of 18.5 to 24.9. An individual with a BMI of between 25 and 29.9 is considered overweight, and having a BMI of 30 or above is considered obese. A person who is underweight may have estrogen levels that are too low, preventing ovulation,  and causing irregular menstruation or stopping menstruation altogether. Being overweight can lead to difficulties with menstruation and ovulation as well. According to Self Magazine, “Not only can insulin resistance lead to type 2 diabetes, but it can also have a negative impact on fertility. Basically, insulin’s job is to move glucose from the bloodstream to the cells. But in cases of insulin resistance, cells “stop listening” to insulin’s request to move glucose into the cells. The body detects that there is lots of glucose in the blood, so, in an effort to help, the pancreas pumps out more and more insulin. And here's where fertility comes into play: Having a high level of insulin in your blood can cause metabolic disturbances that can affect ovulation.” They went onto say, “Insulin resistance, as well as defects in insulin secretion, have been associated with polycystic ovarian syndrome (PCOS), which can also lead to fertility issues. The exact cause of PCOS is unknown, but excess insulin might result in increased androgen production, according to the Mayo Clinic, which can be a problem for ovulation. That said, not everyone with insulin resistance will have PCOS, and women who have insulin resistance without PCOS can also experience ovulatory dysfunction.”

Women aren’t the only ones that should be concerned with weight and infertility, however.

Fertility is not only a female issue. As such, men should be just as cognizant of their weight if their partner is struggling to achieve pregnancy. This is especially true if they are overweight or obese, as it can decrease their sperm count and sperm motility. The Harvard School of Public Health did a study that found, “overweight and obese men are more likely than their normal-weight peers to produce lower numbers of sperm, or even no sperm at all. This could increase the likelihood that they would have difficulty conceiving. While the results don’t prove that excess weight leads to fertility troubles, having a lower sperm count can make it more difficult for men to conceive.” Their report went onto say that, “overweight men were 11 percent more likely to have a low sperm count and 39 percent more likely to have no sperm in their ejaculate. Obese men were 42 percent more likely to have a low sperm count than their normal-weight peers and 81 percent more likely to produce no sperm.”

What Should You Do If You're Struggling To Conceive?

There could be a link between your weight and infertility, but it could be something else entirely. The first step may be to meet with your primary care physician, to have a complete physical performed. If you are overweight, obese, or underweight, it may be time to discuss a diet, nutrition and physical activity plan with them to help you get to a healthy weight. They can also help you determine if there are any vitamin deficiencies in your diet that you should be made aware of, as sometimes these can be linked with fertility too. As part of your physical, they will likely give you a blood test which will reveal if there are any other irregularities you should know about such as thyroid issues, risk of heart attack, cholesterol issues, etc… Once you’ve ruled out weight and other factors as a cause of your infertility, it might then be time to meet with a fertility specialist if you are still struggling to conceive. Should it come to that point, and you’re looking for a fertility doctor, we hope you will think of Center of Reproductive Medicine. We know that infertility is a difficult subject filled with a plethora of unknowns. That’s why we’re such big advocates of education. Things don’t feel as scary or confusing when you can learn more about them. Click here to check out other posts on our blog, and when you’re ready, we’ll be here to help you along in your journey of starting or expanding your family.


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