e days just before, during,and immediately following the ovulation areconsidered unsafe for unprotected intercourse;other days in the cycle are considered safe. Theavoidance of intercourse around ovulation, therhythm method, is the only birth control methodapproved by the Roman Catholic church.Maintenance of calendar records of menstrualcycles proved unreliable, because cycles may varydue to fatigue, colds, or physical or emotionalstress. A woman's body temperature, however,rises slightly during ovulation and remains high untiljust before the next flow begins. Immediatelypreceding the release of the egg, the mucus in thevagina becomes clear and the flow is heavier. Asthe quantity of mucus is reduced, it becomescloudy and viscous and may disappear. Thesesignals can help a woman determine the time whenshe must avoid intercourse to prevent pregnancy.Permanent Contraception Couples who wish tohave no more children or none at all may choosesterilization of the man or of the woman instead ofprolonged use of temporary methods. To beconsidered irreversible, sterilization blocks orseparates the tubes that carry the sperm or theeggs to the reproductive system. The man is stillcapable of ejaculating, but his semen no longercontains sperm. The woman continues tomenstruate and an egg is released each month, butit does not reach her uterus. Neither operationaffects hormone production, male or femalecharacteristics, sex drive, or orgasm. Tubes maybe separated by surgically cutting them, they maybe blocked with clips or bands, or they may besealed using an electric current. The man'soperation, or VASECTOMY, is simpler and isusually performed in a doctor's office or a clinic.The operation for women is usually performed in ahospital or an out-patient surgical center. Some ofthe most recent techniques require a stay of only afew hours. Some soreness and discomfort may beexpected after surgery, occasionally with swelling,bleeding, or infection; the risk of...
