User:K. Jung, UCSF Pharm.D. Candidate 2022/sandbox

Add to PCOS section of obesity and fertility

PCOS has a worldwide prevalence of 3-10%, and is the most common endocrine disorder found in women of reproductive age.

Increasing body weight is also thought to be linked to the development of polycystic ovary syndrome (PCOS). PCOS is a very common endocrine disorder among women who are reproductively active with a prevalence of 5-10%. At least 40% of women diagnosed with PCOS are obese. PCOS diagnosis is defined by the Rotterdam criteria of having at least two of the following criteria: polycystic ovaries, hyperandrogenism, and ovulatory dysfunction. Polycystic ovaries can be viewed by the ultrasound, and it will show multiple, small cysts in the ovaries. Some symptoms that people may experience with PCOS are listed: abnormal menstruation, acne, difficulty with conception, and excessive hair growth.

PCOS is associated with excess levels of androgens (male hormones) or hyperandrogenism. Hyperandrogenism in women results in menstrual abnormalities, insulin resistance, and ovarian dysfunction in the body. Obesity interferes with the Hypothalamic-Pituitary-Ovarian (HPO) Axis. HPO Axis is a tightly regulated cycle of female hormones that control female reproduction. In a female with no history of PCOS, gonadotropin and other steroid hormone release are tightly controlled to choose a follicle for development, and the endometrium lining thickens. The ovary also plays a vital role in releasing steroid hormones for follicular maturation and oocyte development. Then, the egg is released and implanted into the endometrium. In the absence of fertilization of a sperm, the endometrium lining will shed, and menstruation will occur, which is usually a 28-day cycle. Hyperandrogenism can disrupt this cycle and decrease follicular maturation, leading to irregular menstrual cycles or anovulatory cycles.

Obesity in PCOS women amplifies hormonal and metabolic decline, therefore decreasing fertility and oocyte quality in women. In obese women, there is an increased level of insulin circulating the body because of the inability of the body to respond to insulin (insulin resistance). Increased insulin in the blood stimulates the ovaries to produce more androgens, causing hyperandrogenism, which interferes with the HPO Axis.2 In addition, pregnant women with a history of PCOS have an increased risk of gestational diabetes because of insulin resistance. Obese women tend to have increased abdominal fat deposits, which is correlated with reduced menstrual frequency and fertility and increased insulin resistance.

PCOS women with obesity can have an affect on assisted reproductive technology (ART) outcomes. These women undergoing in vitro fertilization (IVF) treatment tend to have smaller oocytes that can decrease their chances of a successful conception.