Obesity and infertility

With an increase in body mass index (BMI), the risk of ovulatory dysfunction increases, which can lead to infertility. Many obese women have to turn to assisted reproductive technologies to get pregnant and have a baby. The number of people suffering from obesity is growing every year. 1.9 billion adults worldwide are overweight or obese.

Obesity is described by BMI, which is the ratio of weight (kg) to height squared (m2). There are four weight categories according to BMI:

  • Underweight (BMI < 18.5 kg/m2)
  • Normal weight (BMI 18.5-24.9 kg/m2)
  • Overweight (BMI 25-29.9 kg/m2)
  • Obesity (BMI>30 kg/m2).

Eating habits and a sedentary, inactive lifestyle are the causes of obesity in women of childbearing age. Obesity is accompanied by changes in steroidogenesis, which affects the secretion of follicle-stimulating and luteinising hormones and leads to anovulation. Obesity can also negatively affect the success of embryo implantation and pregnancy loss. Women with a high BMI who want to have a child often have to undergo infertility treatment. Obese men have lower sperm counts, which also contributes to lower fertility rates. Weight loss through lifestyle changes, drug therapy, and bariatric surgery has a positive effect on fertility.

Obesity is often combined with polycystic ovary syndrome (PCOS), which is characterised by anovulation. Ovulation is restored in women with PCOS after weight loss and medication.

Training tactics for obese women should include:

  • Compensation or elimination of endocrine disorders (if present)
  • Improving insulin sensitivity (in case of carbohydrate metabolism disorders)
  • Reducing body weight

Support of the luteal phase with drugs. To restore regular menstrual function and ovulation, as well as to reduce the risk of pregnancy complications, it is enough to reduce body weight by 10-15% of the initial weight. The first recommendation in case of obesity is to change the way of eating and to lead a more active lifestyle (moderate physical activity). If within 3 months of adherence to these recommendations, a 5% reduction in body weight from the initial value is not achieved, drug therapy should be initiated. Patients with a high BMI should consult a reproductive specialist, endocrinologist, as their reproductive function is affected by excessive body weight.