Effect of a very-low-calorie diet on in vitro fertilization outcomes

Obesity and reproduction: impact and interventions

PURPOSE OF REVIEW

To examine the impact of obesity and potential intervention upon human reproduction in the domain of fertility, fertility treatment, pregnancy and its complications.

RECENT FINDINGS

The prevalence of obesity in women of reproductive age continues to increase, with recent recognition that visceral obesity is associated with greater metabolic disturbances and reduced fecundity, even in ovulating women. Although the efficacy of infertility treatment is reduced by obesity, this effect is not profound and indeed the argument for weight reduction in young women is better serviced by the obesity-dependent increases in perinatal and maternal risks during pregnancy and potential modification of long-term health. Although lifestyle modification alone can induce significant metabolic improvement, resumption of ovulation and reduction of perinatal risks, greater weight loss, and therefore greater potential benefit, can be achieved in combination with pharmacological agents or bariatric surgery.

SUMMARY

Obesity in women has a broad, negative impact upon human reproduction. Specific risks through pregnancy are real and may be addressed by lifestyle modification leading to weight loss and improved insulin sensitivity. Obese women undergoing fertility treatment should be advised of the increased and absolute increased risks they are undertaking, and fertility centres should adopt appropriate strategies.

Polycystic ovary syndrome

Polycystic ovary syndrome is a heterogeneous endocrine disorder that affects about one in 15 women worldwide. The major endocrine disruption is excessive androgen secretion or activity, and a large proportion of women also have abnormal insulin activity. Many body systems are affected in polycystic ovary syndrome, resulting in several health complications, including menstrual dysfunction, infertility, hirsutism, acne, obesity, and metabolic syndrome. Women with this disorder have an established increased risk of developing type 2 diabetes and a still debated increased risk of cardiovascular disease. The diagnostic traits of polycystic ovary syndrome are hyperandrogenism, chronic anovulation, and polycystic ovaries, after exclusion of other conditions that cause these same features. A conclusive definition of the disorder and the importance of the three diagnostic criteria relative to each other remain controversial. The cause of polycystic ovary syndrome is unknown, but studies suggest a strong genetic component that is affected by gestational environment, lifestyle factors, or both.