Ovulation

1. See Also
   1. Natural Family Planning
   2. Infertility
   3. Basal Body Temperature
   4. Cervical Mucus
2. Physiology
   1. Normal ovulatory cycles are 21-35 days in duration
   2. Normal cycles typically vary by only 1-2 days per month
3. History Suggesting Ovulation
   1. Keep a menstrual Diary for several months
      1. Record days of uterine bleeding and amount
      2. Record associated symptoms
   2. Document premenstrual and Menstrual Symptoms
      1. Breast tenderness
      2. Menstrual Cramps
      3. Depressed mood
      4. Mid-cycle pelvic cramping (Mittelschmerz)
4. Signs of Ovulation: Basal Body Temperature (BBT)
   1. Basal Body Temperature increase of 0.3 to 1.0 F
   2. Inaccurate method
      1. Ovulation could occur 6 days before BBT nadir
      2. Ovulation could occur 4 days after BBT nadir
5. Labs indicating Ovulation (most accurate testing)
   1. Mid-luteal Progesterone Level (Day 21)
      1. Level >6.0 ng/ml (19 nmol/L) suggests Ovulation
      2. Level <4.0 ng/ml suggests Anovulation
   2. Morning Urine LH surge testing
      1. Urine LH surge occurs 72 hours before Ovulation
6. Ineffective methods of determining Ovulation
   1. Salivary Ferning
   2. Salivary B-glucuronidase activity
7. Efficacy: Prediction of fertile window
   1. Prediction inaccurate in most women
   2. Days 6-21: 10% probability each day of fertile window
8. References
   1. Guermandi (2001) Obstet Gynecol 97:92-6
   2. Wilcox (2000) BMJ 321:1259-62