Contraception and Sterilization

• Approximately 90% of women of childbearing age use some form of contraception. Despite this, nearly 50% of pregnancies in the United States are unintentional. Of these, 43% result in live births, 13% in miscarriages, and 44% end in elective abortion
• No contraceptive or sterilization method is 100% effective
• Contraceptive methods and their theoretical and actual failure rates

  • No method (85.0%/85.0%)
  • Periodic abstinence (9.0%/25.0%)
  • Withdrawal (4.0%/27.0%)
  • Lactational amenorrhea (2.0%/15.0-55.0%)
  • Male condom (2.0%/15.0%)
  • Female condom (5.0%/21.0%)
  • Diaphragm with spermicide (6.0%/16.0%)
  • Cervical cap with spermicide (Parous women 26.0%/32.0%, Nulliparous women 9.0%/16.0%)
  • Spermicide alone (18.0%/29.0%)
  • Copper-T IUD (0.6%/0.8%)
  • Levonorgestrel IUS (0.1%/0.1%)
  • Combination pill (0.1%/3.0%)
  • Transdermal patch (0.3%/0.8%)
  • Vaginal ring (0.3%/0.8%)
  • Progestin-only pill (0.5%/8.0%)
  • Depo-Provera (0.3%/0.3%)
  • Subdermal implant (0.4%/0.4%)
  • Female sterilization (0.5%/0.5%)
  • Male sterilization (0.1%/0.15%)
• Theoretical efficacy rate refers to the efficacy of contraception when used exactly as instructed. Actual efficacy rate refers to efficacy when used in real life, assuming variations in the consistency of usage
• Natural methods of contraception

  • Periodic abstinence
  • Coitus interruptus
  • Lactational amenorrhea
• Periodic abstinence


  Physiologic form of contraception that emphasizes fertility awareness and abstinence shortly before and after the estimated ovulation period
• Periodic abstinence


  • Requires instruction on the physiology of menstruation and conception and on methods of determining ovulation
  • Requires the woman to have regular, predictable menstrual cycles
  • Ovulation assessment methods may include ovulation prediction kits, basal body temperature measurements, menstrual cycle tracking, cervical mucus evaluation, and/or documentation of any premenstrual or ovulatory symptoms
• The average effectiveness of periodic abstinence is relatively low (55% to 80%) compared to other forms of pregnancy prevention
• Coitus interruptus


  Withdrawal of the penis from the vagina before ejaculation
• The failure rate for coitus interruptus is quite high (27%) compared to other forms of contraception
• Lactational amenorrhea


  Continuation of nursing has long been a widespread method of contraception. After delivery, the restoration of ovulation is delayed because of a nursing-induced hypothalamic suppression of ovulation
• 50% of lactating mothers will begin to ovulate between 6 and 12 months after delivery, even while breastfeeding. Return of ovulation occurs before the return of menstruation
• 15% to 55% of mothers using lactation for contraception subsequently become pregnant
• Enhancing the effectiveness of lactational amenorrhea


  • Breastfeeding should be the only form of nutrition for the infant
  • This method of contraception should be used only as long as the woman is experiencing amenorrhea and only for a maximum of 6 months after delivery
• Barrier methods and spermicides

  • Male condoms
  • Female condoms
  • Diaphragm
  • Cervical caps
  • Vaginal contraceptive foam
  • Vaginal contraceptive suppositories
  • Vaginal contraceptive film
  • Spermicidal gel
• Male condoms


  Latex sheaths placed over the erect penis before ejaculation to prevent the ejaculate from being released into the reproductive tract of the woman
• When properly used, the condom can be 98% effective in preventing conception. The actual efficacy rate in the population is 85% to 90%
• Female condoms


  A pouch made of polyurethane that has a flexible ring at each end, with one ring fitting into the depth of the vagina and the other staying outside the vagina near the introitus
• The failure rate of the female condom is 20% to 25%, somewhat higher than that of the male condom
• Diaphragm


  A dome-shaped latex rubber sheet stretched over a thin coiled rim, with spermicidal jelly placed on the rim and on either side, and placed into the vagina to cover the cervix
• The theoretical effectiveness of the diaphragm approaches 94%. The actual effectiveness rate of the diaphragm with spermicide is 80% to 85%
• Cervical cap


  A small, soft, silicone cap that fits directly over the cervix and is held in place by suction, acting as a barrier to sperm
• The actual efficacy rate of the cervical cap is 68% to 84% (16% to 32% failure rate), depending on the woman's parity
• Spermicides


  Agents that disrupt the cell membranes of spermatozoa and act as a mechanical barrier to the cervical canal, including nonoxynol-9 and octoxynol-9
• When properly and consistently used with condoms, spermicides can have an effectiveness rate as high as 95%. However, in actual usage, the efficacy of spermicides when used alone is only 70% to 75%
• Spermicides do not confer any protection against sexually transmitted infections (STIs) and may make the user more susceptible to STIs including HIV by causing vaginal irritation
• Intrauterine devices (IUDs) available in the United States

  • Copper-T IUD (ParaGard)
  • Levonorgestrel intrauterine system (Mirena)
• Spermicides should not be used by women with HIV or at high risk of contracting HIV, especially in developing nations where contraception and STI prevention are paramount
• For the general public, it is strongly recommended that consistent condom use be employed whenever protection against STIs is desired
• Intrauterine devices (IUDs)


  Devices introduced into the endometrial cavity to prevent pregnancy, used since the 1800s
• In the 1960s and 1970s, IUDs became extremely popular in the United States, but legal ramifications stemming from pelvic infections associated with the Dalkon shield resulted in consumer fear and limited availability of all IUDs
• Currently, only two IUDs are available in the United States: the intrauterine Copper-T IUD (TCu-380A or ParaGard) and the levonorgestrel intrauterine system (LNG-20 or Mirena)
• Despite previous fears, there are nearly 100 million IUD users globally, making the IUD the most widely used method of reversible contraception in the world
• IUD is especially indicated for


  Women in whom oral contraceptives are contraindicated, those who are at low risk for STIs, and in monogamous women of any age
• Levonorgestrel-containing IUD (Mirena)


  Can also be used to treat menorrhagia, dysmenorrhea, and used in postmenopausal women receiving estrogen therapy
• Absolute and relative contraindications for IUD use

  • Known or suspected pregnancy
  • Undiagnosed abnormal vaginal bleeding
  • Acute cervical, uterine, or salpingeal infection
  • Copper allergy or Wilson disease (for ParaGard only)
  • Current breast cancer (for Mirena only)
  • Prior ectopic pregnancy
  • History of STIs in past 3 months
  • Uterine anomaly or fibroid distorting the cavity
  • Current menorrhagia or dysmenorrhea (for ParaGard only)
• Intrauterine devices are introduced into the endometrial cavity


  1. Using a cervical cannula

  2. IUDs have two monofilament strings that extend through the cervix where they can be checked to detect expulsion or migration

  3. The strings also facilitate removal of the device by the clinician
• Mechanism of action for IUDs


  • They act mainly by killing sperm (spermicidal) and preventing fertilization
  • They elicit a sterile inflammatory response resulting in sperm being engulfed, immobilized, and destroyed by inflammatory cells
  • They reduce tubal motility that inhibits sperm and blastocyst transport
  • They do not affect ovulation, nor do they act as abortifacients
  • The addition of levonorgestrel in the Mirena IUD and copper in the ParaGard IUD further augments their mechanisms of action
• Mirena IUD


  • Progesterone thickens the cervical mucus and atrophies the endometrium to prevent implantation
• ParaGard IUD


  • Copper is thought to hamper sperm motility and capitation so sperm rarely reach the fallopian tube and are unable to fertilize the ovum