Understanding Contraception: Options to Help You Plan Your Family
Contraception helps you decide if and when to have a baby. Many different methods are available, so you can choose one that best fits your life, health needs, and future plans. This article explains how well different methods work, the main types, and important things to know about possible side effects or risks.
How Well Does Contraception Work?
The most frequently seen STIs include:
– Perfect use (used exactly as directed every time)
– Typical use (real-life use, including occasional mistakes)
The Pearl Index shows the number of pregnancies that occur among 100 women using the method for one year. A lower number means higher reliability. For example, a Pearl Index of 1 means about 1 pregnancy per 100 women in one year.
Without any contraception, about 85 out of 100 sexually active women will become pregnant within one year. Modern methods can reduce this chance significantly.
Non-Hormonal Methods
These do not affect your hormones and may be preferred if you wish to avoid hormones or have certain medical conditions.
Barrier methods (condoms, diaphragm, sponge, spermicide): Pearl Index 13–21 with typical use. They also provide some protection against sexually transmitted infections.
Side effects: Possible irritation or allergic reactions.
Copper IUD: A small T-shaped device placed inside the uterus. It can remain in place for up to 5-10 years, depending on the specific type of IUD. Pearl Index <1.
Side effects: Heavier or more painful periods (often improves after a few months). Rare risks include expulsion, perforation during insertion, or infection (<1%).
Natural Contraception (Fertility Awareness-Based Methods)
Natural contraception involves tracking your body’s natural signs to identify fertile days and avoiding sex or using a barrier method during those times. Common approaches include counting calendar days, tracking basal body temperature (BBT), monitoring cervical mucus changes, or using symptothermal methods.
These methods have no hormones and no devices, but they require daily attention, accurate tracking, and consistent effort from both partners. With typical use, the Pearl Index is 12–24. Perfect use can be more reliable, but it demands strict adherence.
Hormonal Methods
These prevent pregnancy by stopping ovulation, thickening cervical mucus, and thinning the lining of the uterus.
Combined hormonal (pill, patch, or vaginal ring): Contain both estrogen and progestin. Pearl Index 7–9 with typical use but <1% with perfect use.
Side effects: Nausea, breast tenderness, or irregular spotting, especially in the first few months. Rare serious risks include blood clots, stroke, or heart attack (higher risk if you are a smoker over 35 years of age).
Progestin-only methods (mini-pill, Depo-Provera injection, or Nexplanon implant): These do not contain estrogen which may be a good option for those who want to avoid estrogen, or for those for whom estrogen is contra-indicated. The injection and implant do not require daily action once started which may increase adherence.
Side effects: Irregular bleeding, possible weight gain, or delayed return of normal periods.
Hormonal IUD: Releases progestin locally in the womb. Duration ranges from 3 years (Skyla) to 8 years (Mirena). Often makes periods lighter. Pearl Index <1.
Side effects: Often causes lighter periods or no periods (many women see this as a benefit). Insertion risks are the same as for the copper IUD (cramping, rare expulsion, perforation, or infection <1%).
Long-Acting Reversible Contraception (LARC)
LARC methods are highly reliable and do not require daily action. ACOG and CDC recommend them as a good first choice for many women. These include IUDs (copper or hormonal), which are placed in the office and last 3–10 years depending on the type, and the implant (Nexplanon), a small rod placed under the skin of the upper arm that lasts up to 5 years. Both have a Pearl Index <1.
Side effects: Generally well tolerated. Main issues relate to insertion (cramping or discomfort). Expulsion occurs in about 2–10% of IUD users. No increased cancer risk.
Sterilization
For those who are certain they do not want more children, sterilization is a permanent, reliable and hormone free option – tubal ligation (tube tying) for women or vasectomy for men.
Side effects and risks: Involves surgical risks such as infection or bleeding. Some people may later experience regret, especially if done at a younger age. Although very effective, if pregnancy occurs after tubal ligation (which is rare), there is an increased chance it will be an ectopic pregnancy.
Emergency Contraception
This is used after unprotected sex or when regular contraception fails.
Plan B (levonorgestrel pill): Available without prescription. Most effective when taken within 72 hours, but can be taken up to 5 days.
Ulipristal acetate: Requires a prescription and works up to 5 days after unprotected sex.
Copper IUD: The most effective emergency option when placed within 5 days; it also provides ongoing contraception. The copper IUD should not be inserted if pregnancy is already confirmed or suspected.
Side effects: Common side effects of plan B include nausea or spotting. It does not affect future fertility. It is meant for occasional use; regular contraception is preferable for ongoing prevention.
Take the Next Step
Choosing contraception is a personal decision. Schedule a consultation so we can review your options, answer your questions, and help you select a method that matches your needs and health profile. We provide confidential, up-to-date care tailored to you.
References
1. Berek JS, editor. Berek & Novak’s gynecology. 17th ed. Philadelphia: Wolters Kluwer; 2025.
2. Curtis KM, Nguyen AT, Tepper NK, et al. U.S. Selected Practice Recommendations for Contraceptive Use, 2024. MMWR Recomm Rep. 2024;73(4):1-77.
3. Nguyen AT, Curtis KM, Tepper NK, et al. U.S. Medical Eligibility Criteria for Contraceptive Use, 2024. MMWR Recomm Rep. 2024;73(4):1-124.
4. American College of Obstetricians and Gynecologists. Effectiveness of birth control methods [Internet]. Washington, DC: ACOG; [updated 2025]. Available from: https://www.acog.org/womens-health/infographics/effectiveness-of-birth-control-methods.
5. American College of Obstetricians and Gynecologists. Emergency contraception. FAQ114. Washington, DC: ACOG; 2025 Apr [updated 2025 Apr]. Available from: https://www.acog.org/womens-health/faqs/emergency-contraception.
Maternal–Fetal Medicine Specialist in Bangkok
Dr. Narisra Srikureja Firer (Dr. Niti)
Dr. Niti is a Bangkok-based OBGYN with subspecialty training in Maternal–Fetal Medicine (MFM). She provides comprehensive care for women across all stages of life, including pregnancy care, deliveries, and general gynecological conditions.
She dedicates her time to private practice at Ruamjairak Hospital and Mission Hospital, and serves as a Maternal–Fetal Medicine Consultant at a large government tertiary care center.
To read Dr. Niti’s full bio, click here.
