Does being overweight affect fertility? we tell you everything
Being overweight is a problem in many areas of health. In fact, much has been written about the different effects of excessive weight: cardiovascular problems, mental health, osteoarthritis, a higher prevalence of cancers...
The question is: do overweight and obesity also affect male and female fertility?
Does being overweight or obese reduce the chances of getting pregnant?
The answer is yes. In this article we will see all the nuances of this yes.
Being overweight as a risk factor in fertility
It is believed that approximately 7% of women of reproductive age have some type of fertility problem. Overweight and obesity are one of the greatest risk factors for reproductive success.
On the contrary, it has been shown that weight loss in these patients improves fertility rates.
There is a sufficient number of studies to support the theory that reducing the amount of carbohydrates can reduce blood insulin levels, restore hormonal balance and, thus, promote correct ovulation in women.
Low-carbohydrate diets are capable of optimizing fertility levels in women, and especially in those who suffer from Polycystic Ovary Syndrome (PCOS). You can read more in depth about the Polycystic Ovary Syndrome and its relationship with fertility here.
Social and biological view of overweight
Being overweight is a problem of modern life, but… why does it happen?
A paleolithic body for modern life
How is it possible that biologically we can store fat to the point that it is a detrimental element for the reproduction of the species?
The fat cell is specially designed to store energy reserves, thanks to it humanity has reached where we are, serving as an energy store for the periods of scarcity and hunger that the human being has gone through.
The fat cell or adipocyte “has no end”.
You can store and store without anything stopping you. In case of food shortage, the human body is very well prepared.
It has several physiological mechanisms to get energy from different sources but You only have one resource to deal with excess food: insulin..
The main message of this hormone in the body is to store everything that is not used up in the adipocyte, so that it remains available for what may happen in the future.
Human physiology has changed very little throughout history. That means that even today, the human body is more designed for times of scarcity than for access to food.
The current type of diet – abundant, constant and rich in sugars – triggers insulin levels and favors the storage of all that energy ingested. After all, the body is designed to store valuable energy so that it can be used when needed.
The problem is that it is never necessary to spend these stores anymore because there are never periods of food shortage. So, we accumulate, accumulate and accumulate… And we barely spend.
Our physiology still belongs to the Paleolithic era. The body is not properly adapted to modern life and the result is increasingly higher obesity rates throughout the planet.
beyond aesthetics
An interesting aspect of fat is its distribution within the body. Depending on where it is distributed, it is more or less relevant to health and fertility.
Visceral fat or central fat (in the gut) is more pernicious than peripheral or general fat.
And the problem is not aesthetic.
Fat, which for years has been considered a negligible material in medicine, is today considered just another endocrine organ, that is, an organ capable of producing hormones by itself.
Effects of being overweight on fertility
A situation of excess fat maintained over time not only alters a woman's hormonal balance but also alters the activity of both the ovaries and the endometrium.
Substances are secreted from the fat -leptin, fatty acids and cytokines-, which can hinder the oocyte maturation and even the receptive capacity of the uterus.
So much so that obese women, with a body mass index (BMI) greater than 30, have three times more menstrual disorders than women of normal weight.
In the case of fertility, women who are obese or overweight (BMI of 25) take longer to get pregnant and have a 68% lower chance of success in their first assisted reproductive therapy.
They generally need higher doses of medication to achieve the same hormonal stimulation and have a greater number of cycle cancellations due to lack of stimulation.
Problems for maturation and implantation
The development of a condition called Peripheral Insulin Resistance -which always accompanies situations of overweight and obesity-, produces a hormonal imbalance of both estrogens (female hormone) and androgens (male hormone).
This situation contributes to anovulation and reduced endometrial receptivity, and causes infertility. The inverse relationship between obesity and fertility is scientifically documented.
The good news is that heWeight loss is often able to restore fertility in most cases, favoring a good development of pregnancies and, very especially, the processes that involve assisted reproduction.
Obesity in men also has a weight in the fertility equation. Studies show that obese or overweight men report lower sperm density and a greater number of hormonal alterations.
The mechanism by which obesity prevents ovulation and fertility is still unknown. What is known is that this condition decreases the concentration of certain proteins responsible for transporting sex hormones through the body, necessary for them to perform their function correctly.
Being overweight tends to increase the secretion of several hormones: the male hormone, androgen -favoring polycystic ovary syndrome among other alterations-, the hormone estrogen and the hormone insulin.
Studies carried out at the University of Milan show that the spontaneous pregnancy rate is around 30%, but it can be improved to 40-50% with a weight loss of between 10 and 15%.
They also confirmed the effectiveness of the medication in restoring sensitivity to the hormone insulin and improving the body's ability to ovulate, as the main functions affected by obesity.
Good supervision to achieve progressive weight loss, combined with regular exercise, can restore health and fertility.
How to lose weight to improve fertility
Until a few years ago, studies always presented low-fat and low-calorie diets to show their impact on weight and fertility.
Today, on the other hand, low-carbohydrate diets have gained more value.
Low Carb Diets to Improve Chances of Pregnancy
The requirement is that less than 45% of the nutrients in the diet come from carbohydrates, either in normocaloric or very low-calorie diets. The most current meta-analyses have shown that women with obesity or overweight, with metabolic syndrome, improved equally in values such as waist circumference, total cholesterol, glucose or insulin level than with low-fat diets.
But, in addition, they achieved better results in terms of weight, triglycerides and other high-density lipoproteins, that is, the good cholesterol.
Quality studies have shown that low-carbohydrate diets have a direct impact on the delicate balance of sex hormones, with a direct impact on reproductive capacity.
They manage to lower circulating insulin levels in the blood, improve ovulation rates and with it the expectations of success in fertility over other diets. These diets are especially recommended for women suffering from Polycystic Ovarian Syndrome.
In general, low-calorie diets combined with exercise are more effective in enhancing fertility than other interventions. And weight loss directly impacts improving the ovulation process.
Without a doubt, going to a health professional to help you in the process will be a good decision: diet, movement, psychological support, acupuncture, psychoneuroimmunology…
All this has positive evidence to help you in the way to lose weight. And, in case some other alteration linked to obesity is identified, as is the case of polycystic ovaries, which can help you reverse it as soon as possible.