detecting ovulation

• Determine time of ovulation to abstain from sexual intercourse of days when fertilisation is most likely (periodic abstinence) 
• Not particularly reliable

  • Rely on keeping careful records
  • Difficult to have sex according to a calendar rather than desire 

  Possible to achieve low pregnancy rates if motivated and properly trained
• Rhythm method 

  Based on the egg being available for fertilisation during a period of 3-5 day each menstrual cycle 
• Rhythm method

  Ovulation is likely 14th day (in 28-day cycle) 

  Egg can survive only 2 days unless fertilised

  Sperm can survive for 4 days at most 

  Sexual intercourse should not occur 4 days before and after ovulation

  
• Rhythm method

  Most women do not have exact same cycle each month or exactly 28 days 

  Used in combination with other methods
• Temperature method 

  Sharp drop in body temperature then rise when ovulation occurs

  Take body temperature each morning to determine time of ovulation more accurately 

  Can safely have sex three days after temperature rise 

  
• Mucus method 

  Probable time of ovulation is predicted by observing change in mucus of cervix 
• Mucus method

  Immediately after menstruation, tissue of vaginal entrance feel dry

  Approaching ovulation, mucus can be detected

  • First is cloudy and sticky
  • Cervix secretes more, clearer, feels slippery and strands will stretch without breaking 

  Day of ovulation, peak of clear mucus

  Becomes cloudy afterwards 

  Intercourse safe when no mucus, 3+ days after last day of clear mucus 
• Symptothermal method

  Rhythm method and combination of temperature and mucus 

  
  

  Fertility Monitor has been developed to measure changes in body temperature and cervical mucus