Contraception: MCCQE1 Preparation Guide

Introduction

Contraception is a high-yield topic for the MCCQE1 and represents a fundamental aspect of primary care and gynecology in Canada. As a future Canadian physician, you are expected to demonstrate the CanMEDS roles of Medical Expert, Communicator, and Health Advocate when counseling patients on reproductive health.

In Canada, approximately 40% of pregnancies are unintended. Effective contraceptive counseling requires a patient-centered approach, understanding the efficacy, mechanism of action, contraindications, and non-contraceptive benefits of various methods available in the Canadian market.

Classification of Contraceptive Methods

For MCCQE1 preparation, it is useful to categorize methods by their efficacy tiers. This helps in “tiered counseling,” a strategy recommended to present the most effective methods first.

Hormonal Contraception

Combined Hormonal Contraception (CHC)

Includes the Combined Oral Contraceptive (COC), Transdermal Patch (Evra), and Vaginal Ring (NuvaRing).

Mechanism:

1. Inhibits ovulation (primary mechanism via estrogen/progestin negative feedback).
2. Thickens cervical mucus.
3. Thins endometrial lining.

Progestin-Only Methods

Useful for patients with contraindications to estrogen.

Intrauterine Contraception (IUC)

IUCs are critical for MCCQE1 clinical reasoning scenarios involving heavy menstrual bleeding or long-term contraception needs.

1. Levonorgestrel-Releasing Intrauterine System (LNG-IUS)

• Brands in Canada: Mirena (52mg), Kyleena (19.5mg), Jaydess (13.5mg - discontinued in some markets but relevant historically).
• Mechanism: Local progestin effect thickens mucus, thins endometrium, inhibits sperm motility.
• Duration: 5-8 years (depending on device and updated guidelines).
• Non-Contraceptive Benefit: First-line treatment for menorrhagia (heavy menstrual bleeding) and dysmenorrhea.

2. Copper Intrauterine Device (Cu-IUD)

• Brands in Canada: Mona Lisa, Liberte.
• Mechanism: Copper ions are spermicidal; creates sterile inflammatory reaction.
• Pros: Hormone-free, immediate return to fertility, effective for 3-10 years.
• Cons: May increase menstrual bleeding and cramping (dysmenorrhea).

Emergency Contraception (EC)

Canadian physicians and pharmacists can provide EC. Candidates must know the window of efficacy.

Clinical Counselling Strategy: The GATHER Approach

For OSCEs and clinical reasoning, structure your counseling using this adapted framework.

Canadian Guidelines & Special Populations

Adolescents

• Confidentiality: In Canada, no specific age of consent for medical treatment exists in many provinces; it relies on the “Mature Minor” capability. You do not need parental consent if the adolescent understands the risks and benefits.
• SOGC Guideline: LARC should be presented as a first-line option.

Postpartum

• Breastfeeding: Estrogen may decrease milk supply. Avoid CHC for first 6 weeks (or until breastfeeding is established).
• Safe Options: POP, Injection, Implant, and IUDs are safe immediately postpartum (though IUD expulsion rate is slightly higher if inserted immediately post-placenta).

Perimenopause

• Contraception is required until 1 year of amenorrhea if age > 50, or 2 years if age < 50.
• The LNG-IUS is excellent for providing contraception and protecting the endometrium if the patient requires estrogen for vasomotor symptoms (HRT).

Key Points to Remember for MCCQE1

• ACHES Mnemonic for CHC complications: Abdominal pain (mesenteric ischemia/liver), Chest pain (PE/MI), Headache (Stroke), Eye problems (Retinal vein thrombosis), Severe leg pain (DVT).
• Migraine with Aura: Absolute contraindication to Estrogen. Use Copper IUD, LNG-IUS, or POP.
• Smokers > 35: Absolute contraindication to Estrogen.
• Quick Start: It is safe to start contraception on any day of the cycle if pregnancy is reasonably excluded. Use backup (condoms) for 7 days.
• Enzyme Inducers: Antiepileptics (carbamazepine, phenytoin) and Rifampin induce liver enzymes, reducing hormonal contraception efficacy. Management: Use Copper IUD or Depot Injection (unaffected) or high-dose hormones (less preferred).

# Medical Abbreviations
*   **COC:** Combined Oral Contraceptive
*   **LARC:** Long-Acting Reversible Contraception
*   **VTE:** Venous Thromboembolism
*   **LNG-IUS:** Levonorgestrel-Releasing Intrauterine System
*   **WHO MEC:** World Health Organization Medical Eligibility Criteria

Sample Question

A 34-year-old female presents to your clinic to discuss contraceptive options. She has a history of migraine headaches with aura (visual scotoma) occurring approximately once a month. She is a non-smoker. She is currently in a monogamous relationship and has two children. She reports heavy menstrual periods that affect her quality of life. She desires a reliable method of contraception but wishes to avoid daily medication.

Which one of the following contraceptive methods is most appropriate for this patient?

• A. Combined transdermal patch (Evra)
• B. Combined vaginal ring (NuvaRing)
• C. Levonorgestrel-releasing intrauterine system (LNG-IUS)
• D. Copper intrauterine device (Cu-IUD)
• E. Progestin-only pill (Norethindrone)

Explanation

The correct answer is:

• C. Levonorgestrel-releasing intrauterine system (LNG-IUS)

Reasoning: This patient has a history of migraine with aura, which is a WHO MEC Category 4 (absolute contraindication) for combined hormonal contraception (estrogen + progestin) due to an increased risk of ischemic stroke. Therefore, the Patch (Option A) and Vaginal Ring (Option B), which contain estrogen, are contraindicated.

While the Progestin-only pill (Option E) is safe for women with migraines with aura, the patient specifically requested to avoid daily medication.

The Copper IUD (Option D) is a safe, non-hormonal option and avoids daily medication; however, the patient reports heavy menstrual periods. A Copper IUD often worsens menorrhagia and dysmenorrhea.

The LNG-IUS (Option C) is the best choice because:

1. It is progestin-only (safe for migraine with aura).
2. It is a LARC (no daily medication).
3. It significantly reduces menstrual blood loss and is a first-line treatment for menorrhagia.

References

1. Black, A., et al. (2015). “Canadian Contraception Consensus (Part 1 of 4).” Journal of Obstetrics and Gynaecology Canada (JOGC).
2. Black, A., et al. (2016). “Canadian Contraception Consensus (Part 3 of 4): Chapter 7 - Intrauterine Contraception.” JOGC.
3. Guilbert, E., et al. (2016). “Canadian Contraception Consensus (Part 4 of 4): Chapter 9 - Emergency Contraception.” JOGC.
4. World Health Organization. (2015). Medical Eligibility Criteria for Contraceptive Use. 5th ed.
5. Medical Council of Canada. MCCQE Part I Objectives: Contraception.