What are the different types of birth control available, including hormonal and non-hormonal options? Can you explain how each method works biologically to prevent pregnancy, including details about their mechanisms of action? Furthermore, what are the typical effectiveness rates (both with perfect use and typical use) associated with each method, and what are the common side effects or risks associated with each? Finally, how do factors like age, health history, and lifestyle choices influence the suitability of different birth control methods for an individual?

Answer

Birth control methods are diverse and work through various mechanisms to prevent pregnancy. They can be broadly categorized into:

1. Hormonal Methods: These methods use synthetic hormones (estrogen and/or progestin) to prevent ovulation, thicken cervical mucus, and/or thin the uterine lining.

  • Combined Hormonal Contraceptives (CHCs): Contain both estrogen and progestin.
    • Pills: Taken daily. Work primarily by suppressing ovulation. Examples include monophasic, biphasic, and triphasic pills, varying in hormone dosage throughout the cycle. Common brand names include Yaz, Loestrin, and Ortho Tri-Cyclen.
    • Patch (Ortho Evra, Xulane): Applied weekly to the skin. Delivers a continuous dose of hormones.
    • Vaginal Ring (NuvaRing, Annovera): Inserted into the vagina and releases hormones over three weeks. Removed for one week to allow for withdrawal bleeding. Annovera can be washed and reinserted for a year.
  • Progestin-Only Methods: Contain only progestin.
    • Pills (Mini-Pill): Must be taken at the same time every day. Work mainly by thickening cervical mucus and thinning the uterine lining; may also suppress ovulation in some women. Examples include Camila, Errin, and Nora-BE.
    • Injection (Depo-Provera): Given every three months. Suppresses ovulation.
    • Implant (Nexplanon): A small rod inserted under the skin of the upper arm. Releases progestin for up to three years. Suppresses ovulation and thickens cervical mucus.
    • Hormonal IUD (Mirena, Kyleena, Liletta, Skyla): Inserted into the uterus. Releases progestin locally. Thickens cervical mucus, thins the uterine lining, and may suppress ovulation. Effective for 3-8 years, depending on the brand.

2. Barrier Methods: These methods physically block sperm from reaching the egg.

  • Male Condoms: A sheath worn over the penis during intercourse. Collects semen and prevents it from entering the vagina. Made of latex, polyurethane, or polyisoprene.
  • Female Condoms: A pouch inserted into the vagina before intercourse. Lines the vagina and prevents sperm from entering. Made of polyurethane or nitrile.
  • Diaphragm: A shallow, dome-shaped cup inserted into the vagina to cover the cervix. Used with spermicide. Must be fitted by a healthcare provider.
  • Cervical Cap (FemCap): A smaller version of the diaphragm that fits snugly over the cervix. Used with spermicide. Must be fitted by a healthcare provider.
  • Spermicides: Chemical substances that kill sperm. Available as foams, gels, creams, suppositories, and films. Inserted into the vagina before intercourse. Often used in combination with other barrier methods. Examples include nonoxynol-9.

3. Long-Acting Reversible Contraception (LARC): These are highly effective methods that require little maintenance once in place.

  • Hormonal IUD (Mirena, Kyleena, Liletta, Skyla): (See description above in Hormonal Methods)
  • Copper IUD (Paragard): Inserted into the uterus. Does not contain hormones. Prevents fertilization by creating a toxic environment for sperm and disrupting sperm motility. Effective for up to 10-12 years.
  • Implant (Nexplanon): (See description above in Hormonal Methods)

4. Permanent Methods (Sterilization): These methods are intended to be permanent.

  • Tubal Ligation (Female Sterilization): Surgical procedure that blocks or cuts the fallopian tubes, preventing eggs from reaching the uterus. Can be done laparoscopically, during a C-section, or after vaginal delivery.
  • Essure (No longer available): A metal coil inserted into the fallopian tubes to block them.
  • Vasectomy (Male Sterilization): Surgical procedure that blocks or cuts the vas deferens, preventing sperm from being released during ejaculation.

5. Fertility Awareness-Based Methods (FABMs): These methods involve tracking a woman’s menstrual cycle and identifying fertile days to avoid intercourse or use barrier methods during those times. Require diligent tracking and understanding of one’s body.

  • Calendar Method (Rhythm Method): Tracking menstrual cycles to predict ovulation. Requires charting cycles for at least six months to identify the fertile window.
  • Basal Body Temperature (BBT) Method: Taking temperature every morning before getting out of bed. A slight rise in temperature indicates ovulation.
  • Cervical Mucus Method (Billings Method): Observing changes in cervical mucus throughout the cycle. Mucus becomes clear, stretchy, and slippery around the time of ovulation.
  • Symptothermal Method: Combining BBT, cervical mucus observations, and other symptoms (e.g., breast tenderness, mittelschmerz) to identify the fertile window.
  • Standard Days Method (SDM): A simplified calendar method that uses a string of beads (CycleBeads) to track fertile days. Requires cycles to be consistently between 26 and 32 days long.

6. Emergency Contraception (EC): Used after unprotected sex to prevent pregnancy.

  • Emergency Contraceptive Pills (ECPs):
    • Levonorgestrel ECPs (Plan B One-Step, Take Action, My Way): Available over-the-counter. Contain a high dose of progestin. Work by delaying or inhibiting ovulation. Most effective when taken within 72 hours of unprotected sex, but can be used up to 120 hours.
    • Ulipristal Acetate (Ella): Requires a prescription. A selective progesterone receptor modulator. Can be taken up to 120 hours after unprotected sex. May be more effective than levonorgestrel ECPs, especially for women with higher BMIs.
  • Copper IUD (Paragard): Can be inserted up to five days after unprotected sex. Most effective form of emergency contraception. Also provides ongoing contraception for up to 10-12 years.

7. Lactational Amenorrhea Method (LAM): A temporary method of contraception based on the natural infertility that occurs when a woman is exclusively breastfeeding. Requires the baby to be under six months old, exclusively breastfed on demand (day and night), and the mother’s period has not returned.