What is the recommended approach for prescribing oral combined birth control to a female patient of reproductive age?

How to Prescribe Oral Combined Birth Control

Start combined oral contraceptives (COCs) on the same day as the visit ("quick start") in healthy, non-pregnant patients, prescribe a monophasic formulation containing 30-35 μg ethinyl estradiol with levonorgestrel or norgestimate, provide up to 1 year supply at a time, and instruct patients to use backup contraception for the first 7 days. 1

Pre-Prescribing Assessment

Medical Eligibility Screening

Absolute contraindications (Category 4 - do not prescribe): 2, 1

• Age ≥35 years AND smoking ≥15 cigarettes per day
• Severe uncontrolled hypertension (≥160/100 mm Hg)
• Current or history of venous thromboembolism or thrombophilia
• Migraines with aura or focal neurologic symptoms
• Complicated valvular heart disease
• Ongoing hepatic dysfunction or active liver disease
• Current or history of breast cancer

Relative contraindications (Category 3 - usually not recommended): 2

• Age ≥35 years AND smoking <15 cigarettes per day
• Multiple cardiovascular risk factors

Required Pre-Initiation Steps

Blood pressure measurement is the only required examination before prescribing COCs. 1 A pelvic examination, Pap smear, or other laboratory tests are not necessary before initiation and should not delay access to contraception. 2

Choosing the Formulation

First-Line Recommendation

Prescribe a monophasic COC containing 30-35 μg ethinyl estradiol with either levonorgestrel or norgestimate. 1 These second-generation progestins have the most favorable safety profile regarding venous thromboembolism risk compared to third and fourth-generation progestins. 1

Among low-dose pills, there are no clear data suggesting one formulation is superior to another for most users, so the lowest copay option on the patient's insurance formulary is often appropriate. 1

Alternative Formulations

For patients with hypertension concerns: Consider drospirenone-containing pills, which have anti-mineralocorticoid effects that may help mitigate blood pressure increases. 1

For acne treatment: Four FDA-approved formulations exist: norgestimate/ethinyl estradiol, norethindrone acetate/ethinyl estradiol/ferrous fumarate, drospirenone/ethinyl estradiol, or drospirenone/ethinyl estradiol/levomefolate. 1

Dosing Considerations

Standard pill packs contain 21-24 hormone pills followed by 4-7 placebo pills. 1 Extended or continuous cycle regimens can be useful for conditions exacerbated cyclically, such as migraines without aura, epilepsy, irritable bowel syndrome, or endometriosis. 1

Important caveat: Formulations containing 20 μg ethinyl estradiol require stricter adherence, as seven consecutive days of pill-taking is necessary to reliably prevent ovulation. 1 Studies show more follicular activity when 20 μg pills are missed compared to 30 μg formulations. 2

Initiation Protocol

Quick Start Method (Preferred)

Patients can start COCs on the same day as the visit regardless of menstrual cycle timing. 1 This approach removes unnecessary barriers to contraceptive access. 2

Backup contraception requirements: 1, 3

• If started within the first 5 days of menstrual bleeding: No backup needed
• If started >5 days after menstrual bleeding began: Use backup contraception for the first 7 days
• For patients with infrequent menses: Start at any time if reasonably certain not pregnant, with backup contraception for 7 days

Alternative Start Methods

Sunday Start: The first active pill is taken on the first Sunday after menstruation begins. Backup contraception is required for the first 7 consecutive days. 3

Day 1 Start: The first active pill is taken on the first day of menstruation. No backup contraception is needed. 3

Patient Counseling on Missed Pills

One Pill Late (<24 hours)

• Take the late pill as soon as possible
• Continue remaining pills at usual time
• No additional contraceptive protection needed
• Emergency contraception not usually needed 2

One Pill Missed (24 to <48 hours)

• Take the most recent missed pill immediately (discard any other missed pills)
• Continue remaining pills at usual time (even if taking two pills same day)
• Use backup contraception or avoid intercourse until pills taken for 7 consecutive days
• If pills missed in Week 3: Omit hormone-free interval by finishing current pack and starting new pack next day 2
• Consider emergency contraception if pills missed in Week 1 and unprotected intercourse occurred in previous 5 days 2

Two or More Pills Missed (≥48 hours)

• Take the most recent missed pill immediately
• Continue remaining pills at usual time
• Use backup contraception or avoid intercourse until pills taken for 7 consecutive days
• If missed in Week 3: Skip hormone-free interval and start new pack immediately
• If unable to start new pack immediately: Use backup contraception until new pack pills taken for 7 consecutive days
• Consider emergency contraception if missed during Week 1 and unprotected intercourse in previous 5 days 2

Prescribing Logistics

Prescribe up to 1 year supply at a time. 1 This recommendation from the CDC removes unnecessary barriers to continued contraceptive use and reduces unintended pregnancy rates. 2

Drug Interactions to Counsel About

Medications That Reduce COC Effectiveness

Require alternative contraception or backup methods: 1, 3

• Rifampin and rifabutin (only antimicrobials with significant interaction)
• Anticonvulsants: phenytoin, carbamazepine, barbiturates, primidone, topiramate, oxcarbazepine
• Griseofulvin

Important note: Lamotrigine levels decrease significantly when co-administered with COCs, potentially reducing seizure control. 3

Medications That Do NOT Reduce Effectiveness

Patients can safely use these without backup contraception: 1

• Tetracycline-class antibiotics (doxycycline, minocycline)
• Broad-spectrum antibiotics
• Antifungals
• Antiparasitics

Contraindicated Combinations

Do not prescribe COCs with: 3

• HCV drug combinations containing ombitasvir/paritaprevir/ritonavir (with or without dasabuvir) due to potential for ALT elevations
• Glecaprevir/pibrentasvir is not recommended due to potential for ALT elevations

Common Side Effects and Management

Expected Side Effects

Unscheduled bleeding is the most common adverse effect, particularly with extended-cycle regimens. 2 It is generally not harmful and decreases with continued use, being highest during the first 3-6 months. 2

Other common transient effects: 1

• Headache (14% of users)
• Nausea
• Metrorrhagia (8% of users)

Important reassurance: Weight gain and mood changes have not been reliably linked to COC use. 1

Managing Unscheduled Bleeding

If clinically indicated, consider underlying gynecological problems: inconsistent use, drug interactions, cigarette smoking, STD, pregnancy, or new pathologic uterine conditions (polyps, fibroids). 2

If no underlying problem found and patient wants treatment: 2

• Advise 3-4 consecutive days hormone-free interval (not recommended during first 21 days or more than once per month)
• If bleeding persists and unacceptable, counsel on alternative contraceptive methods

Serious Risks to Discuss

The most serious adverse event is venous thromboembolism (VTE). 1 The baseline risk increases from 1 per 10,000 woman-years to 3-4 per 10,000 woman-years during COC use. 1 This risk remains significantly lower than the risk during pregnancy (10-20 per 10,000 woman-years). 1

For stroke risk minimization: Lower doses of ethinyl estradiol are recommended. 1 For patients with specific stroke risk factors, progestin-only or nonhormonal contraception may be more appropriate. 1

Follow-Up Requirements

Blood pressure monitoring is the primary safety requirement for women on long-term COC therapy. 1 Blood pressure measurements can be obtained in nonclinical settings to facilitate ongoing monitoring. 1

Routine follow-up visits are not required for most women. 2 Removing unnecessary follow-up procedures helps patients access and successfully use contraception. 2

Special Populations

Smokers Under Age 35

Smoking is not a contraindication to COC use in individuals younger than 35 years old. 1 However, smoking should be discouraged. 1

Postpartum Initiation

COCs can be initiated 4 weeks postpartum in women who elect not to breastfeed. 3 The increased risk of thromboembolic disease associated with the postpartum period must be considered. 3

If starting postpartum before first period, instruct patient to use another method of contraception until an active pill has been taken daily for 7 days. 3

Breastfeeding Women

Nursing mothers should be advised not to use COCs but to use other forms of contraception until completely weaned. 3 Small amounts of oral contraceptive steroids are identified in human milk, and COCs may interfere with lactation by decreasing quantity and quality of breast milk. 3

Women Over 45 Years

Women aged >45 years generally can use COCs (Category 2) based on age alone. 2 However, they might have chronic conditions or risk factors that render use unsafe; use U.S. MEC to guide safe use. 2

Do not arbitrarily discontinue COCs at age 40 or 45—the safety profile supports use throughout reproductive years in healthy, non-smoking women. 1

Non-Contraceptive Benefits to Highlight

COCs provide multiple health benefits beyond contraception: 1

• Decreased menstrual cramping and blood loss
• Improvement in acne through anti-androgenic properties
• Treatment of conditions including anemia, severe dysmenorrhea, endometriosis, abnormal uterine bleeding
• Long-term use (>3 years) provides significant protection against endometrial and ovarian cancers

COCs are completely reversible with no negative effect on long-term fertility. 1