Obesity is a common metabolic disturbance and defined as excessive accumulation of body fat. According to Asian classification, a body mass Index (BMI) for normal person should be between 18.5 kg/m2 – 22.9 kg/m2 , a BMI of ≥ 23.0 kg/m2 is classified as overweight and a BMI of ≥ 27.5 kg/m2 as obese. The prevalence of obesity and overweight is rapidly increasing in both men and women and has become an epidemic worldwide. Obesity has detrimental influence on all body systems, including the reproductive health.
EFFECT OF MALE OBESITY IN INFERTILITY
The obesity has negative influence on reproductive function among men through various mechanisms, including lower serum testosterone, higher serum estradiol levels, impaired spermatogenensis and erectile dysfunction, increased testicular heat, and elevated inflammatory mediators. In normal men, gonadotropin-releasing hormone(GnRH) is produced and released from the hypothalamus, leading to the stimulation and production of the follicle-stimulating hormone (FSH) and LH from their anterior pituatory. FSH and LH then act on the testicle to stimulate spermatogenensis and steroidogenesis respectively. Whereas, the obese men have normal or decreased LH levels, decreased total testosterone levels, and reduced SHBG levels. It is very important to keep in mind that the effects of male obesity on fertility are likely multifactorial. Moreover, obesity is often associated with metabolic disorders, including metabolic syndrome, hyperlipidemia, cardiovascular disease and pro-inflammatory state, all of which could lead to male sub-fertility.
As compared to healthy weight men, over-sized or obese men have decreased sperm quality (in concentration and motility, declined acrosome reaction and increased sperm DNA damage) and lower embryo implantation rates. Also, the excessive visceral adiposity in obese males could result in changes in their hormone levels, resulting in chronic inflammation in the reproductive tract and increased scrotal temperature due to high-fat content in the scrotum area, all these can reduce the sperm quality and cause male infertility risk.
EFFECT OF FEMALE OBESITY IN INFERTILITY
Obesity impacts the women health across their reproductive lifespan with adverse effects on not only fertility and short-term complications of pregnancy, but also on longer term health outcomes for both women and their children. As compared to healthy women, overweight women have a higher chances of menstrual dysfunction and an-ovulation. Moreover, the obese women are at a high risk for sub-fecundity and sub-fertility, conception rates, miscarriage rates, and many other pregnancy complications are increased in these women. They tend to have poor reproductive outcomes in natural as well as assisted conception or reproduction such as ovulation induction, IVF/ICSI, and ovum donation cycles.
EFFECTS OF OBESITY DURING PREGNANCY
The maternal obesity and increased risk of multiple serious pregnant complications have both the short and long term negative effects. These risks include pregnancy induced hypertension and pre-eclampsia, GDM (gestational diabetes) and antenatal depression. Women with obesity are more likely to experience induction of labor and cesarean section and they are also more likely to have a stillbirth as compared to normal weight women.
NUTRITION MANAGEMENT
Weight loss is the gold standard of treatment in both men and women with a high BM.
Overweight and obese patients should be encouraged to lose weight before planning to conceive to reduce the poor obstetrical outcomes due to obesity.
The writer is a Senior Nutritionist, Cloudnine Group of Hospitals, Chandigarh.