Understanding Modern Contraceptives: Zoely and Qlaira
Zoely and Qlaira represent a newer generation of combined oral contraceptives (COCs) that have moved away from the traditional synthetic estrogen (ethinylestradiol) found in many older pills [1.2.2]. Instead, they both utilize a form of estradiol that is identical to the estrogen naturally produced in the body [1.2.2, 1.3.2]. This has made them popular options for women seeking contraception, particularly those in perimenopause [1.2.2]. However, despite this core similarity, the answer to 'Is Zoely the same as Qlaira?' is no. They have distinct formulations, dosing regimens, and indications that set them apart.
Core Differences in Active Ingredients
The primary distinction between Zoely and Qlaira lies in their unique combination of hormones.
- Zoely: Combines 2.5 mg of nomegestrol acetate (a progestogen) with 1.5 mg of estradiol (as hemihydrate) in each active pill [1.3.2, 1.3.3]. Nomegestrol acetate is a highly selective progestogen known for its strong ability to suppress ovulation [1.3.3].
- Qlaira: Contains estradiol valerate (a prodrug that converts to estradiol in the body) and dienogest (a progestogen) [1.4.1, 1.4.3]. Unlike Zoely, the doses of these hormones change throughout the cycle [1.4.2].
Dienogest, the progestin in Qlaira, has recognized antiandrogenic properties, which can be beneficial for some users, while nomegestrol acetate in Zoely is noted for its high selectivity to progesterone receptors with no androgenic effects [1.3.3, 1.4.4].
Dosing Regimen: Monophasic vs. Quadraphasic
A significant pharmacological difference is how the hormones are delivered throughout the menstrual cycle.
Zoely's Monophasic Approach
Zoely is a monophasic pill [1.2.1]. This means that every active pill in the pack contains the exact same dose of hormones: 2.5 mg of nomegestrol acetate and 1.5 mg of estradiol [1.3.2]. The regimen consists of 24 active white tablets followed by 4 inactive (placebo) yellow tablets [1.6.2]. This constant hormone dose during the active phase and a short 4-day placebo interval is designed to provide stable hormone levels and a greater margin of contraceptive efficacy [1.2.1, 1.3.4].
Qlaira's Quadraphasic System
In contrast, Qlaira is quadraphasic (or four-phasic) [1.2.1, 1.4.3]. It is designed to mimic the natural fluctuations of a menstrual cycle by providing varying doses of hormones at different stages. A 28-day pack includes [1.4.2, 1.4.3]:
- 2 dark yellow tablets with 3 mg estradiol valerate.
- 5 medium red tablets with 2 mg estradiol valerate and 2 mg dienogest.
- 17 light yellow tablets with 2 mg estradiol valerate and 3 mg dienogest.
- 2 dark red tablets with 1 mg estradiol valerate.
- 2 white placebo tablets.
This dynamic dosing includes an estrogen step-down and a progestin step-up, aiming for good cycle control with only a two-day hormone-free interval [1.4.3].
Comparison of Zoely and Qlaira
| Feature | Zoely | Qlaira |
|---|---|---|
| Estrogen Type | Estradiol (as hemihydrate) [1.3.2] | Estradiol Valerate (converts to estradiol) [1.4.1] |
| Progestogen Type | Nomegestrol Acetate [1.3.1] | Dienogest [1.4.1] |
| Dosing Schedule | Monophasic (24 active, 4 placebo) [1.2.1, 1.6.2] | Quadraphasic (26 active, 2 placebo) [1.2.5, 1.4.3] |
| Hormone Dose | Constant dose in all active pills [1.2.1] | Variable doses throughout the cycle [1.4.2] |
| Hormone-Free Interval | 4 days [1.6.2] | 2 days [1.4.3] |
| Licensed for Heavy Menstrual Bleeding | No, but may cause lighter bleeds [1.8.1] | Yes, in women who also desire contraception [1.10.1, 1.10.2] |
Approved Indications and Off-Label Uses
Both pills are highly effective for contraception [1.3.3, 1.4.4]. However, Qlaira has an additional licensed indication. In Europe and other regions, Qlaira is officially approved for the treatment of heavy menstrual bleeding (HMB) in women without organic pathology who wish to use oral contraception [1.10.1, 1.10.4]. Clinical trials have shown it can significantly reduce menstrual blood loss [1.10.2].
While Zoely is not licensed for HMB, its 24/4 regimen often results in lighter, shorter, or even absent withdrawal bleeds compared to traditional 21/7 pills [1.2.3, 1.8.1]. This can be a desirable side effect for many users, but they should be counseled about the potential for irregular bleeding patterns, especially in the first few months [1.2.1, 1.11.1].
Side Effects and User Experience
Common side effects for both pills are typical of COCs and can include headache, mood changes, breast pain, and nausea [1.6.4, 1.10.2]. Some studies and user reports have noted specific differences:
- Zoely: Acne and weight gain were more frequently reported in some clinical trials comparing Zoely to a drospirenone-containing pill [1.2.1]. It is also associated with a higher likelihood of absent withdrawal bleeds [1.8.3].
- Qlaira: Its unique dosing can be beneficial for those sensitive to progestogens or who experience hormonal dips, but the variable doses mean missing a pill can be more complicated [1.2.5, 1.7.1]. Unexpected bleeding can occur, particularly in the first few cycles [1.10.3].
As with all combined hormonal contraceptives, both carry a risk of venous thromboembolism (VTE), or blood clots, and should not be used by individuals with certain risk factors [1.6.3, 1.7.2].
Switching Between Zoely and Qlaira
Because both are combined oral contraceptives, switching from one to the other is generally straightforward. Healthcare professionals typically advise finishing the current pack and starting the new one immediately without taking a break or placebo pills from the old pack [1.9.1, 1.9.4]. This ensures continuous contraceptive coverage by preventing a drop in hormone levels [1.9.4]. However, a consultation with a doctor is essential to manage the transition and understand any potential for temporary side effects like spotting [1.9.1].
Conclusion
To conclude, Zoely and Qlaira are fundamentally different medications despite their shared use of body-identical estrogen. Zoely is a monophasic pill with a constant dose of nomegestrol acetate and a 4-day placebo interval. Qlaira is a quadraphasic pill with varying doses of dienogest and a shorter 2-day placebo interval, which is also licensed to treat heavy menstrual bleeding. The choice between them depends on individual needs, medical history, and how one responds to the specific progestogen and dosing regimen. A thorough discussion with a healthcare provider is crucial to determine the most suitable option.
For more detailed information, consult authoritative sources such as the European Medicines Agency (EMA). Find more information here.
