Chapter 10. ABNORMAL MENSTRUAL CYCLES

1. Chapter 10. ABNORMAL MENSTRUAL CYCLES Reid L. Norman, PhD Professor, Pharmacology and Neuroscience, TTUHSC

2. Learning Objectives • Describe the terminology of normal and abnormal menstrual function • List the causes of menstrual dysfunction • Understand the consequences of menstrual dysfunction in young women • Know the health concerns due to menstrual dysfunction

3. Menstrual cycle terminology • Eumenorrhea – regular menstrual cycles of 25-38 days • Oligomenorrhea – menstrual cycles of 39-90 days • Amenorrhea – when menstrual cycles are more than 90 days or when menstruation is absent

4. Eumenorrhea • Normal, regular menstruation which lasts for 3-5 days but a range of 2-7 days is considered normal • Average blood loss is 35 cc or a little over an ounce • This usually reflects regular, cyclic ovulation and no underlying organic problems

5. Oligomenorrhea • When menstrual cycles are irregular and longer than 39 days • This condition is common when women are just starting (at puberty) or ending (at menopause) their reproductive life

6. Causes of oligomenorrhea • PCOS – polycystic ovary syndrome • Ovary becomes filled with cysts • Excess androgen production • Excess facial and body hair • Usually anovulatory cycles • 5 – 10 % of women will experience this sometime during their life

7. Causes of oligomenorrhea • Low energy availability – possible causes • Dieting • Eating disorders • Excessive exercise • Body image concerns • Other stresses (psychological) may also contribute to this problem

8. Causes of oligomenorrhea • Hypothyroidism • Hyperprolactinemia • Chronic disease • Social unrest (such as wars) • Move to a new, unfamiliar environment • Go away to college • Incarceration

9. Amenorrhea • Pregnancy is the most common cause • Anorexia nervosa – eating disorder, potentially lethal • Female athlete triad • Amenorrhea • Eating disorder • osteopenia

10. Amenorrhea • Loss of bone is a major risk with this condition • Generally, this condition is due to loss of hypothalamic GnRH secretion which results in low LH and FSH release and low estrogen and progesterone levels