Obesity and oocyte quality: significant implications for ART and emerging mechanistic insights

Macarena B Gonzalez, Rebecca L Robker, Ryan D Rose, Obesity and oocyte quality: significant implications for ART and emerging mechanistic insights, Biology of Reproduction, Volume 106, Issue 2, February 2022, Pages 338–350, https://doi.org/10.1093/biolre/ioab228

Key messages:

  • Obese women experience more challenges on the pathway to motherhood
  • Women with higher BMI have fewer chances of spontaneous pregnancy, and are at higher risk of poorer outcomes at each step of the assisted reproductive technology process
  • Obesity adversely impacts oocyte quality in women
  • Obesity leads to reduced oocyte developmental competence (the ability of an oocyte to be fertilised, develop into an embryo and produce healthy offspring)
  • Obesity has long-lasting effects in offspring health

 

———————————————————————————————–

The WHO reports that worldwide obesity has nearly tripled since 1975. This impacts fertility.

Abstract: “The prevalence of obesity in adults worldwide, and specifically in women of reproductive age, is concerning given the risks to fertility posed by the increased risk of type 2 diabetes, metabolic syndrome, and other noncommunicable diseases.”

“Obese women have a higher chance of miscarriage, gestational diabetes, pregnancy complications, birth defects, and most worryingly, a higher risk of stillbirth and neonatal death. The potential for compounding effects of assisted reproductive technology (ART) on pregnancy complications and infant morbidities in obese women has not been studied.”

“There is still much debate in the (fertility) field on whether these poorer outcomes are mainly driven by defects in oocyte quality, abnormal embryo development, or an unaccommodating uterine environment, however the clinical evidence to date suggests a combination of all three are responsible.”

The medical industry generally describe obesity as excessive fat accumulation that may impair health – and the associated implications around the impact on fertility has now been checked and confirmed, through laboratory research studies, to reduce the chances for spontaneous pregnancy.

However, this big news, isn’t bad news.

Systemic health, like a normal BMI (19-25) and healthy diet, increase a person’s chances of being successful in their assisted reproductive technology (ART).

Dr Ryan Rose (PhD) says, “Considering there are now more women of reproductive age with a higher BMI, it is important for us at Fertility SA to identify the underlying causes by which obesity damages the oocyte (egg), and how we can provide treatments to mitigate the negative impacts that obesity has. Of course, other lifestyle factors also contribute such as alcohol consumption and smoking, however we now know that fundamentally “healthy body really does mean healthy baby”.”

While this paper focuses on women’s health and oocyte quality, evidence has previously shown that it is equally as important for a man’s fertility and/or sperm donors to remain in good health.

Dr Ryan Rose (PhD) goes so far as to suggest. “Systemic health is important to IVF success. The quality of gametes (sperm and oocyte/eggs) are the major contributor to success rates in IVF. “

Obesity is observed when a person’s body mass index (BMI) is 30 or greater.

Fertility SA suggests that significant health benefits can occur with as little as 5-10% weight loss. However treatment involves a long-term plan for making lifestyle changes.

A supportive environment is fundamental in shaping people’s choices, by making the choice of healthier foods and regular physical activity and therefore preventing overweight and obesity.

 

Next steps for patients?

WHO suggest at the individual level, people can:

  1. limit energy intake from total fats and sugars;
  2. increase consumption of fruit and vegetables, as well as legumes, whole grains and nuts; and
  3. engage in regular physical activity (150 minutes spread through the week for adults).

Fertility SA recommend services such as the Adelaide based ‘re:you health’ who use a multi-disciplinary approach to weight loss and work very closely with a team of dietitians, exercise physiologists and psychologists.

 

Article References:

Title: Obesity and oocyte quality: significant implications for ART and emerging mechanistic insights

Macarena B Gonzalez, Rebecca L Robker, Ryan D Rose

Biology of Reproduction, Volume 106, Issue 2, February 2022, Pages 338–350, https://doi.org/10.1093/biolre/ioab228

Published: 17 December 2021

Article: https://academic.oup.com/biolreprod/article-abstract/106/2/338/6464687

WHO Obesity and Overweight Key Facts: https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight

The BMI is a simple index of weight-for-height that is commonly used to classify overweight and obesity in adults. It is defined as a person’s weight in kilograms divided by the square of his height in meters (kg/m2). It should always be considered a rough guide because it may not correspond to the same degree of fatness in different individuals.  https://reyouhealth.com.au/resources/bmi-calculator

Recent Posts

Your Fertility Your Way

To find out more, click the button below to find out how we can start the process