What are the available birth control options for females?

Birth Control Options for Females

Long-acting reversible contraception (LARC) with intrauterine devices (IUDs) or subdermal implants are the most effective reversible contraceptive options, with failure rates less than 1% per year, and should be considered first-line for most women. 1, 2

Contraceptive Options by Effectiveness

Highest Effectiveness (Failure Rate <1% per year)

Long-Acting Reversible Contraception (LARC):

• Copper IUD (Cu-IUD): Provides highly effective long-term contraception and can also serve as emergency contraception when inserted within 5 days of unprotected intercourse 1, 3
• Levonorgestrel-releasing IUD (LNG-IUD): Particularly valuable for women who cannot or choose not to use estrogen-containing methods 1, 3
• Subdermal implants (etonogestrel): Release progestin continuously and are highly effective 1, 2

LARC methods demonstrate superior 12-month adherence rates (86%) compared to oral contraceptive pills (55%), and contraceptive failure rates are significantly lower (0.27 vs 4.55 per 100 women-years) 1. For women under 21 years, failure rates with short-acting methods are twice as high as in women 21 years or older, making LARC particularly important for younger women. 1

Moderate Effectiveness (Failure Rate 4-9% per year with typical use)

Combined Hormonal Contraceptives (CHCs):

• Combined oral contraceptive pills (COCs): Contain both estrogen and progestin; approximately 5-9% of women become pregnant in the first year with typical use 1, 2
• Transdermal contraceptive patch: Releases 150 μg norelgestromin and 20 μg ethinyl estradiol daily 1
• Vaginal contraceptive ring: Releases 120 μg etonogestrel and 15 μg ethinyl estradiol daily 1

First-line COC formulations should contain levonorgestrel or norethisterone combined with ethinyl estradiol 35 micrograms or less, as these have relatively low risk of venous thromboembolism. 4 Pills containing 20 micrograms of ethinyl estradiol with levonorgestrel result in fewer side effects and comparable cycle control to higher-dose pills 5.

Progestin-Only Pills (POPs):

• Approximately 9% failure rate with typical use 1
• Women who frequently miss POPs should consider an alternative method that is less user-dependent 1

Injectable Contraception (DMPA):

• Depot medroxyprogesterone acetate given every 3 months 1
• Failure rate approximately 0.3% with perfect use, 3% with typical use 6

Timing and Initiation Guidelines

For Combined Hormonal Contraceptives:

• Can be started at any time if reasonably certain the woman is not pregnant 1
• If started within the first 5 days of menstrual bleeding, no backup contraception is needed 1
• If started >5 days since menstrual bleeding started, abstain from intercourse or use backup contraception for 7 days 1

Postpartum breastfeeding women:

• Should NOT use combined hormonal contraceptives during the first 3 weeks after delivery due to increased venous thromboembolism risk 1
• Generally should not use CHCs during the fourth week postpartum due to potential effects on breastfeeding 1

Emergency Contraception

Copper IUD is the most effective emergency contraception option, followed by ulipristal acetate, then levonorgestrel, with combined estrogen-progestin regimens being least effective. 7, 3

Ulipristal Acetate (30 mg):

• Effective throughout the entire 120-hour (5-day) window after unprotected intercourse 7
• May be more effective than levonorgestrel in women who are overweight or obese 7, 3
• After use, barrier contraception or abstinence is needed for 14 days or until next menstrual period 7

Levonorgestrel:

• Single dose of 1.5 mg or split dose (0.75 mg twice, 12 hours apart) 1
• Effectiveness decreases after 72 hours 7

Special Populations and Considerations

Women with cancer or recent cancer treatment:

• LARC with IUDs or implantable contraceptives are preferred first-line options 1
• Combined hormonal contraceptive methods should be avoided in women with active cancer or treated for cancer in the past 6 months due to venous thromboembolism risk 1
• For women with history of breast cancer treated with tamoxifen, levonorgestrel-containing IUS may be preferable as it reduces tamoxifen-induced endometrial changes without increasing breast cancer recurrence risk 1

Women with irregular cycles:

• Standard Days Method (fertility awareness) requires cycles of 26-32 days; women with two or more cycles <26 or >32 days within any year should consider another method due to higher pregnancy risk 1

Managing Common Side Effects

Bleeding Irregularities:

• For Cu-IUD users with unscheduled spotting or heavy bleeding: NSAIDs for 5-7 days 1, 3
• For LNG-IUD users: NSAIDs for 5-7 days or hormonal treatment with COCs or estrogen for 10-20 days if medically eligible 1
• For DMPA users: Irregular bleeding and amenorrhea are common; enhanced counseling about expected bleeding patterns reduces discontinuation 1

Important caveat: Breakthrough bleeding is one of the most common reasons for OC discontinuation, and after discontinuation most women switch to less-effective methods or no method, potentially increasing unintended pregnancy rates 5.

Follow-Up Recommendations

No routine follow-up visits are required for any contraceptive method, but women should be advised:

• To return at any time to discuss side effects or problems or if they want to change methods 1, 3
• When IUD or implant needs removal or when reinjection is needed for injectables 1, 3
• Blood pressure should be monitored during routine visits for women using CHCs 1, 3

Risk Profile

Venous Thromboembolism Risk:

• Estrogen-containing methods increase VTE risk from 2-10 events per 10,000 women-years to 7-10 events per 10,000 women-years 2
• Progestin-only and nonhormonal methods are associated with rare serious risks 2

Additional Benefits:

• Hormonal contraceptives can improve conditions associated with menstrual cycle hormonal changes, including acne, endometriosis, and premenstrual dysphoric disorder 2