Progestin-Only Pills (POPs) with Less Weight Gain in Canada
Among progestin-only pills available in Canada, those containing desogestrel or norethindrone are associated with less weight gain compared to other hormonal contraceptive options, particularly depot medroxyprogesterone acetate (DMPA). 1, 2
Weight Impact of Different Progestin-Only Contraceptives
Progestin-Only Pills (POPs)
- Weight gain is rarely reported as a side effect with norethindrone-containing POPs 3
- POPs generally show limited evidence of significant weight gain, with most studies reporting mean gains less than 2 kg over 12 months 2
- Different progestins have variable androgenic/anti-androgenic profiles, which can influence potential weight effects 1, 4
Comparative Weight Effects
- Medroxyprogesterone acetate (DMPA) injectable contraceptive shows more consistent evidence of weight gain compared to POPs 1, 2
- In studies comparing POPs to non-hormonal methods, weight changes were generally not significantly different 2
- Implant users showed slightly greater weight gain compared to non-hormonal IUD users (0.47-1.10 kg difference) 2
Available POPs in Canada
- Norethindrone (Micronor, Movisse) - first generation progestin with minimal weight effects 3, 5
- Desogestrel (Cerazette) - newer generation progestin with favorable metabolic profile 6, 7
Considerations When Choosing POPs
Advantages of POPs
- Appropriate for women who cannot or should not take estrogen 2
- Safer option for women with cardiovascular risk factors 4
- Can be used during breastfeeding 7
Potential Disadvantages
- Menstrual irregularity is the most frequently reported side effect 3
- Require stringent adherence for optimal effectiveness (5-9% typical failure rate) 4
- Must be taken at the same time each day for maximum effectiveness 1
Body Composition Considerations
- Limited studies on POPs and body composition show that hormonal contraceptive users may experience changes in body composition (increased fat mass, decreased lean mass) compared to non-hormonal method users 2
- These changes may occur even without significant changes in total body weight
Clinical Recommendations
For patients concerned about weight gain:
- Consider norethindrone or desogestrel POPs as options with minimal weight effects
- Copper IUD remains the most weight-neutral option if hormonal methods are not required 4
For patients with additional cardiovascular risk factors:
- POPs are generally safer than combined hormonal contraceptives 1
- Monitor blood pressure regularly
For patients requiring high effectiveness:
- Counsel on the importance of taking POPs at the same time each day
- Consider long-acting reversible contraceptives (LARCs) if adherence is a concern 4
Pitfalls and Caveats
- Individual responses to progestins vary significantly - what causes weight gain in one person may not affect another
- Perceived weight gain is a common reason for contraceptive discontinuation, though actual measured weight gain is often minimal
- Appropriate counseling about typical weight changes (generally less than 2 kg) may help improve continuation rates 2
- Regular follow-up (within 3 months of initiation) is recommended to address any side effects promptly 4