What are the types and brand names of Progestin-Only Pills (POP), also known as the mini-pill?

Types of Progestin-Only Pills (POPs) and Their Brand Names

Progestin-only pills (POPs), also known as mini-pills, are a type of oral contraceptive that work primarily by thickening cervical mucus rather than inhibiting ovulation, and are available in several formulations with different progestin types and dosages. 1

Types of Progestin-Only Pills

• Traditional POPs: These contain lower doses of progestins and require strict adherence to timing (must be taken within 3 hours of the same time each day) 1

• Desogestrel-containing POPs: These newer formulations (75 mcg desogestrel) provide more consistent ovulation inhibition and allow for a 12-hour window for taking the pill, offering efficacy comparable to combined oral contraceptives 2

Common Brand Names

• Norethindrone-based POPs (traditional):

  • Micronor (0.35 mg norethindrone) 3
  • Nora-BE (0.35 mg norethindrone) 3
  • Camila (0.35 mg norethindrone) 3
  • Errin (0.35 mg norethindrone) 3

• Desogestrel-based POPs (newer formulation):

  • Slynd (4 mg drospirenone) - a newer POP with a 24-hour missed pill window 2

Effectiveness and Mechanism of Action

• POPs work primarily by thickening cervical mucus, making it difficult for sperm to reach the egg 1

• Unlike combined hormonal contraceptives, traditional POPs do not consistently inhibit ovulation, which contributes to their lower effectiveness compared to combined methods 1

• With typical use, approximately 9 out of 100 women become pregnant in the first year of using POPs 4

• Desogestrel-containing POPs show higher effectiveness (Pearl index of 0.41 crude, 0.14 adjusted) due to more consistent ovulation inhibition 2

Important Considerations for Use

• POPs must be taken consistently at the same time each day, with traditional POPs requiring administration within a 3-hour window 1

• A dose is considered missed if taken more than 3 hours late for traditional POPs 1

• If a dose is missed, users should:

  • Take one pill as soon as possible
  • Continue taking pills daily at the same time
  • Use backup contraception for 2 consecutive days of correct pill use
  • Consider emergency contraception if unprotected intercourse occurred 1

• POPs are generally not recommended as first-choice contraceptives for healthy adolescents due to the strict timing requirements and potential for irregular bleeding 1

Side Effects and Management

• Irregular bleeding is the most common side effect and reason for discontinuation, affecting up to 25% of users 5

• Bleeding patterns may include:

  • Increased frequency of bleeding
  • Lengthened cycles
  • Breakthrough bleeding
  • Spotting
  • Prolonged bleeding 5

• Management of bleeding irregularities may include:

  • NSAIDs for 5-7 days of treatment
  • Counseling about expected bleeding patterns 4

Appropriate Candidates for POPs

• Breastfeeding women (POPs do not affect milk production) 1

• Women with contraindications to estrogen use, such as:

  • History of venous thromboembolism
  • Hypertension
  • Migraine with aura
  • Age ≥35 years who smoke 1, 6

• Women in the immediate postpartum period 1

• Women who require strict adherence to daily pill-taking may be better candidates for longer-acting progestin methods like implants or IUDs 1

Cautions and Follow-up

• No routine follow-up visit is required after initiating POPs, but women should be advised to return if they experience side effects or want to change methods 1

• At other routine visits, healthcare providers should:

  • Assess satisfaction with the method
  • Evaluate any health status changes that might affect POP use
  • Consider assessing weight changes if the woman is concerned 1