Starting Oral Contraceptives: A Practical Approach
For patients seeking oral contraception, a combined oral contraceptive (COC) containing levonorgestrel or norethisterone with ≤35 mcg ethinyl estradiol is the recommended first-line option for most women. 1
Initial Selection Considerations
- COCs are the most commonly used reversible contraceptive method in the US, with typical use pregnancy rates of 4-7% per year 2
- First-line options should be pills containing levonorgestrel or norethisterone combined with ≤35 mcg of ethinyl estradiol due to their:
- Established effectiveness
- Relatively low risk of venous thromboembolism
- Widespread availability 1
- Before starting any hormonal contraceptive, blood pressure measurement is required 3
- No other examinations or tests are mandatory before starting COCs or progestin-only pills (POPs) 3
When to Start Oral Contraceptives
- COCs can be started at any time if the provider is reasonably certain the patient is not pregnant 3
- If starting within 5 days of menses onset, no backup contraception is needed 3
- If starting >5 days after menses onset, use backup contraception (e.g., condoms) or abstain from intercourse for 7 days 3, 4
- For POPs containing norethindrone or norgestrel, backup contraception is needed for 2 days if started >5 days after menses 3
- For drospirenone POPs, backup contraception is needed for 7 days if started >1 day after menses 3
Starting Regimens
Sunday Start
- Take first active pill on the first Sunday after menstruation begins 5
- Use backup contraception for the first 7 days if not starting during the first 5 days of the menstrual cycle 5
- Benefits include weekend-only withdrawal bleeding for many users 5
Day 1 Start
- Take first active pill on the first day of menstruation 5
- No backup contraception needed when started on day 1 of menstruation 5
- May be easier for patients to remember 5
Managing Missed Pills
For combined oral contraceptives:
- If one pill is missed (<24 hours late): Take the missed pill as soon as possible and continue the pack as usual; no backup needed 3
- If two consecutive pills are missed (24-48 hours late): Take the most recent missed pill immediately, continue the pack, and use backup contraception for 7 days 3
- If three or more consecutive pills are missed (≥48 hours late): Take the most recent missed pill immediately, continue the pack, and use backup contraception for 7 days 3
- If pills are missed in the last week of active pills: Omit the hormone-free interval and start a new pack immediately 3
Special Considerations
- For postpartum women who are not breastfeeding, COCs can be started 21-42 days after delivery, depending on VTE risk factors 3
- For breastfeeding women, COCs are generally not recommended until at least 21 days postpartum, with POPs being preferred 3
- Women taking medications that may reduce contraceptive effectiveness (e.g., certain anticonvulsants, rifampin) should consider alternative methods or use backup contraception 3
- Emergency contraception should be considered if pills are missed in the first week and unprotected intercourse occurred in the previous 5 days 3
Non-Contraceptive Benefits
- COCs can improve conditions related to hormonal fluctuations, including:
- Additional benefits include:
Common Pitfalls to Avoid
- Failing to use backup contraception when starting COCs after day 5 of the menstrual cycle 3, 4
- Not following proper missed pill protocols, especially during the first week of the cycle 3
- Overlooking drug interactions that may reduce contraceptive effectiveness 3
- Not considering extended or continuous regimens for patients who might benefit from fewer withdrawal bleeds 1
- Forgetting to counsel on what to do if vomiting or severe diarrhea occurs within 3 hours of taking a pill (treat as a missed pill) 3