Nutrition Through the Life Cycle, Chapter 3 PDF

Chapter 3 Preconception Nutrition: Conditions and Interventions Copyright © 2017 Cengage Learning. All Rights Reserved.  F...

Chapter 3 Preconception Nutrition: Conditions and Interventions Copyright © 2017 Cengage Learning. All Rights Reserved.  Female Reproductive System (cont’d.) Copyright © 2017 Cengage Learning. All Rights Reserved. HPO axis with hormonal regulations and feedback loops.  Introduction Specific preconceptional and periconceptional nutrition-related conditions – May influence fertility or the course and outcome of pregnancy Obesity, underweight, negative energy balance, eating disorders, diabetes, polycystic ovary syndrome, phenylketonuria, celiac disease, etc. Copyright © 2017 Cengage Learning. All Rights Reserved. Obesity and infertility Overweight/obesity – Overweight and obese women should receive counseling on the roles of diet and physical activity in reproductive health Loss of 5–10% of body weight can restore ovulation Should be treatment of first choice for obese woman and men with fertility problems Obesity and infertility Overweight/obesity – Being overweight or obese can contribute to a variety of fertility issues PCOS Insulin resistance Issues with menstruation and ovulation – Obesity reduces sperm quality Simple diet and exercise interventions can be used to reverse the damaging effects of obesity on sperm function – Male obesity impairs offspring metabolic and reproductive health  Obesity and infertility Increased fat tissue enhanced endogenous and exogenous steroidal hormones and increase storage of lipid soluble steroids Changes in metabolism and excretion of hormones or altered production of steroid hormone binding proteins (SHBG) Changes of estrogen receptor Enhanced peripheral conversion of adrenal androgens to additional estrogens in adipose tissue Excessive estrogen feedback to HPO axis and inhibits ovary function Copyright © 2017 Cengage Learning. All Rights Reserved.  Obesity and infertility Weight reduction methods – Focus on behavioral goals and skills Meal planning and physical activities – Medications or weight loss surgery may be indicated Copyright © 2017 Cengage Learning. All Rights Reserved. Diabetes and Infertility – Type 1 and type 2 – Gestational diabetes – Poorly controlled diabetes can contribute to infertility in both men and women – Chronic high blood glucose levels affect hormone levels – Men with diabetes are twice as likely to suffer from low testosterone than are men without diabetes – Carbohydrate counting tends to be an effective management strategy regardless of diabetes type  Polycystic Ovary Syndrome (PCOS) and Fertility Leading cause of female infertility – Five to ten percent of reproductive age women – Many with PCOS are obese or have high levels of intra-abdominal fat The cause is uncertain – Insulin resistance is the leading candidate Copyright © 2017 Cengage Learning. All Rights Reserved.  How hyperinsulinemia is linked to hyperandrogenemia Insulin acts synergistically with LH to enhance androgen production in the ovary. Insulin decreases hepatic synthesis and secretion of sex hormone-binding globulin, the hormone that binds testosterone in the circulation, thus increasing the amount of free testosterone that is biologically available Copyright © 2017 Cengage Learning. All Rights Reserved. Hyperinsulinemia and obesity  Nutritional Management of PCOS Primary goal is to increase insulin sensitivity – Insulin-sensitizing drugs Diet recommendations – Lean proteins, whole grains, fruits and vegetables, regular meals, non-fat dairy, and low-glycemic index carbohydrates Weight loss and exercise are recommended Copyright © 2017 Cengage Learning. All Rights Reserved. Underweight and fertility – Women with low BMIs may develop anovulation and amenorrhea – BMI