Obesity and Infertility

One of the best established connections between obesity and reproductive problems is the link between obesity and infertility. Obesity decreases the rates of successful pregnancy in natural conception cycles.

Obesity is defined by an extraordinarily high Body Mass Index (BMI) in which the index is a reflection of body fat content. Around 1 in 4 women are at least overweight as per surveys and studies. The rates are higher among women facing problems of conception.

Along with several other sexual health problems caused by obesity, infertility is an important one leading to the disturbing trend of need for and failure of assisted reproductive techniques for conception.

Impact Of Obesity On Male Fertility

Male obesity in reproductive-age men has nearly tripled in the past 30 years and coincides with an increase in male infertility worldwide. There is now emerging evidence that male obesity impacts negatively on male reproductive potential not only reducing sperm quality, but in particular altering the physical and molecular structure of germ cells in the testes and ultimately mature sperm.

Recent data has shown that male obesity also impairs offspring metabolic and reproductive health suggesting that paternal health cues are transmitted to the next generation with the mediator mostly likely occurring via the sperm.

Obesity And Anovulation

Obesity is likely to cause insulin resistance that is linked to anovulation or failure of a woman to produce the egg from each ovary each month. Insulin levels and obesity also lead to altered sex hormones, high androgens (male hormones). Only 5% loss of body weight can increase in ovulation rates and reduces biochemical abnormalities.

Studies show that in obese women with anovulation, the underlying cause is most likely due to polycystic ovary syndrome (PCOS). PCOS is associated with obesity or overweight along with symptoms of high male hormone secretion such as hairiness, acne, high cholesterol level and insulin resistance.

Obesity And Miscarriage

Obesity raises the rate of miscarriage and thus decreases successful pregnancy rates among obese women. This could be due to various causes including:
• Poor quality of eggs or ovum
• Defective implantation or reception of the fertilized egg onto the womb mainly due to insulin resistance
• Defective and altered levels of hormones that help in sustaining pregnancy

Obesity And Hormones

Obesity leads to decrease in testosterone, follicle stimulating hormone, inhibin B and sex hormone binding globulin. This leads to low sperm count and quality in obese men.

In obese women there is increase in androgen metabolism and elevated estrogen levels. Obese men show low estrogen and low testosterone levels as well.


The prevalence of obesity and overweight are increasing and have become an epidemic worldwide. Obesity has detrimental influences on all systems, including reproductive health. The prevalence of obesity in infertile women is high, and it is well known that there is an association between obesity and infertility.

The relationship between obesity and reproductive functions is still being explored. Overweight women have a higher incidence of menstrual dysfunction and anovulation. Overweight and obese women are at a high risk for reproductive health. The risk of sub fecundity and infertility, conception rates, miscarriage rates, and pregnancy complications are increased in these women.