Contraceptive Effects

Contraceptive Effectiveness & Side Effects

A woman tends to choose birth control based on what she considers to be the most convenient and effective method for her. However, it’s important to weigh carefully the risks and side effects of each method.

Using contraceptives cannot guarantee the prevention of pregnancy. Contraceptives were used during the month of conception in 48% of unintended pregnancies.1

Male Condom

  • 82-98% effective at preventing pregnancy2
  • 60-79% effective at preventing STDs3

Female Condom

  • 79-95% effective at preventing pregnancy4

Diaphragm or Cervical cap

  • 84-94% effective at preventing pregnancy5
  • Increases risk of vaginal infection, making a woman more vulnerable to contracting STDs6

Birth Control Pill

  • 91-99% effective at preventing or terminating pregnancy7
  • Makes a woman’s reproductive tract more suseptible to infection, increasing her risk of contracting an STD by 30%.8
  • Multiplies risk of heart attack by up to 2.3 and risk of stroke by up to 2.29
  • Increases risk of glioma, a rare brain cancer, by 50% with short-term use. Five years of birth control pill use doubles a woman’s risk.10
  • Listed by the World Health Organization as a Class 1 carcinogen for increased risk of breast and liver cancers11
  • For nearsighted women, six months of using the pill has been shown to increase nearsightedness 2 or 3 times.12

Depo-Provera Shot

  • 94-99% effective at preventing pregnancy13
  • Associated with decreased bone mineral density, weight gain and increased risk of breast cancer14

The Patch

  • 91-99% effective at preventing pregnancy15
  • Multiplies risk of stroke by 3.216

Implant / IUD

  • 99% effective at preventing or terminating pregnancy17
  • 47% of implant users experience adverse effects, including severe acne and weight gain18 

  1. Finer LB, Henshaw SK (2006). Disparities in rates of unintended pregnancy in the United States, 1994 and 2001. Perspect Sex Repro H, 38(2): 90-6. 

  2. Centers for Disease Control and Prevention (2012). Contraception. Retrieved from www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm 

  3. The American College of Obstetricians and Gynecologists (2011). “How to prevent sexually transmitted diseases.” FAQ009. 

  4. Centers for Disease Control and Prevention (2012). Contraception. Retrieved from www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm 

  5. Centers for Disease Control and Prevention (2012). Contraception. Retrieved from www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm 

  6. Rosenberg MJ, Davidson AJ, Chen JH, Judson FN, Douglas JM (1992). Barrier contraceptives and sexually transmitted diseases in women: a comparison of female-dependent methods and condoms. Am J Public Health. 82(5):669-74. 

  7. Centers for Disease Control and Prevention (2012). Contraception. Retrieved from www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm 

  8. Rosenberg MJ, Davidson AJ, Chen JH, Judson FN, Douglas JM (1992). Barrier contraceptives and sexually transmitted diseases in women: a comparison of female-dependent methods and condoms. Am J Public Health. 82(5):669-74. 

  9. Lidegaard Ø, Løkkegaard E, Jensen A, Skovlund CH, Keiding N (2012). “Thrombotic stroke and myocardial infarction with hormonal contraception.” N Engl J Med, 366(24): 2257-66. 

  10. Andersen L, Friis S, Hallas J, Ravn P, Kristensen BW, Gaist D (2014). Hormonal contraceptive use and risk of glioma among younger women a nationwide case-control study. Br J Clin Pharmacol. DOI: 10.1111/bcp.12535 [ePub ahead of print]. 

  11. International Agency for Research on Cancer (1999). Hormonal Contraception and Post-Menopausal Hormonal Therapy. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, 72: 288-94. 

  12. American Society of Health System Pharmacists (2010). AHFS Drug Information 2010: Bethesda, MD, p. 3112. 

  13. Centers for Disease Control and Prevention (2012). Contraception. Retrieved from www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm 

  14. Bigrigg A, Evans M, Gbolade B, Newton J, Pollard L, Szarewski A, Thomas C, Walling M (2000). Depo Provera. Position paper on clinical use, effectiveness and side effects. Br J Fam Plann, 26(1):52-3. 

  15. Centers for Disease Control and Prevention (2012). Contraception. Retrieved from www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm 

  16. Lidegaard Ø, Løkkegaard E, Jensen A, Skovlund CH, Keiding N (2012). “Thrombotic stroke and myocardial infarction with hormonal contraception.” N Engl J Med, 366(24): 2257-66. 

  17. Centers for Disease Control and Prevention (2012). Contraception. Retrieved from www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm 

  18. Urbancsek J (1998). Nonmenstrual adverse events with Implanon®. Contraception, 58: 109S-115S.