Investigating the Physiological Effects of Weight Loss on Male Fertility

Investigating the Physiological Effects of Weight Loss on Male Fertility

The purpose of this study is to determine the physiological effects of weight loss on seminal parameters in male participants with reduced reproductive capacity. Learning more about the physiological role of weight loss on reproductive function and metabolic profile of overweight and obese men may give us a better understanding of male fertility and improve the management of patients with reduced fertility. The effects of weight loss on seminal quality are not well understood.

Participants will receive dietary supplements or National Health Service (NHS) advice on healthy eating to achieve weight loss.

Inclusion Criteria:

• Body mass index (BMI) ≥ 30 kg/m^2 [Part: 1, 2& 3]
• Evidence of reduced reproductive capacity (e.g. reduced sperm concentration [applicable for study B]

Exclusion Criteria:

• History of undescended testes, testicular surgery or mumps infection
• Hormonal therapy such as testosterone or selective oestrogen receptor modulators
• History of systemic cytotoxic therapy or pelvic radiotherapy
• Chronic systemic disease, such as cardiac, renal or liver failure
• At least one of the following:

Alcohol intake >30 units per week Smoking daily Recreational drug use at a frequency not less than weekly

• Acute illness likely to affect the result of study
• Impaired ability to provide full consent to take part in the study
• An occupation requiring strenuous physical exercise that may require a high energy diet