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 problems, osteoarthritis, a higher prevalence of cancer...
The question is: do overweight and obesity also affect female and male fertility?
Does being overweight or obese reduce your chances of getting pregnant?
The answer is yes. In this article we are going to see all the nuances of this yes.
Overweight as a risk factor in fertility
Approximately 7% of women of reproductive age are believed to have some type of fertility problem. Overweight and obesity are one of the biggest risk factors for achieving reproductive success.
In contrast, 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 insulin levels in the blood, 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 vision 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 harmful 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 human beings have gone through.
The fat cell or adipocyte “has no end.”
You can store and store without anything slowing you down. In case of food shortage, the human body is very well prepared.
It has several physiological mechanisms to obtain 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 in the adipocyte everything that is not spent, 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 it can be used when necessary.
The problem is that it is never necessary to use up these stores 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 high 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 for health and fertility.
Visceral fat or central fat (in the gut) is more harmful 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 another endocrine organ, that is, an organ capable of producing hormones on its own.
Effects of being overweight on fertility
A situation of excess fat maintained over time not only alters the woman's hormonal balance but also alters the activity of both the ovaries and the endometrium.
Substances - leptin, fatty acids and cytokines - are secreted from fat, 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 normal weight women.
In the case of fertility, women who are obese or overweight (BMI of 25) take longer to achieve pregnancy and are less likely to succeed in their first assisted reproduction therapy.
They generally require higher doses of medication to achieve the same hormonal stimulation and have a greater number of cycle cancellations due to lack of stimulation.
Problems with 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 producing anovulation and reducing 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 the good development of pregnancies and, especially, processes that involve assisted reproduction.
Obesity in men also plays a role 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 usually increases 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 indicate that the spontaneous pregnancy rate is around 30%, but can be improved to 40-50% with a weight loss of between 10 and 15%.
They also confirmed the effectiveness of the medication in recovering 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 diets low in fat and calories to show their impact on weight and fertility.
Nowadays, however, low-carbohydrate diets have gained more value.
Low carbohydrate diets to improve pregnancy chances
The requirement is that less than 45% of dietary nutrients come from carbohydrates, whether in normocaloric or very low calorie diets. The most recent meta-analyses have shown that obese or overweight women, with metabolic syndrome, improved in the same way in values such as waist circumference, total cholesterol, glucose or insulin levels as with low-fat diets.
But they also achieved better results in terms of weight, triglycerides and other high-density lipoproteins, that is, 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 the levels of insulin circulating in the blood, improve ovulation ratios and thus the expectations of success in fertility over other diets. These diets are especially recommended for women who suffer from Polycystic Ovary Syndrome.
In general, low-calorie diets along with exercise are more effective at boosting 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 of this has positive evidence to help you in the way to lose weight. And, in case any other alteration linked to obesity is identified, such as polycystic ovaries, they can help you reverse it as soon as possible.
