Q. Is there anything new for women to take to prevent pregnancy? Can you compare them to the many options that have been available for decades?
A. While many birth control methods remain the same (pills, IUDs, implants, patches, etc.), there are two available options have entered the contraceptive landscape in the last few years, Slynd and Nextstellis.
Slynd is a progestin-only oral contraceptive using drospirenone 4mg. Compare this to the 3mg dose of drospirenone found in some combination oral contraceptives. Slynd has its positives and negatives. On the plus side, it offers a great choice for those women who prefer to take an oral contraceptive and cannot take estrogen. Plus, drospirenone is far more forgiving for women who find it challenging to take their “pill” at the same time each day. However, progestins may cause some irregular bleeding and/or spotting. As well, drospirenone is linked to a risk of hyperkalemia (high potassium), especially if taking other potassium-raising medications. Therefore potassium should be closely monitored in women taking Slynd.
Nextstellis is a relatively new combined oral contraceptive (COC) containing a novel estrogen (estetrol, “E4”) plus drospirenone as the progesterone. The same considerations apply to Nexstellis as they do with Slynd with respect to the hyperkalemia and irregular bleeding. Estetrol is touted as a “native” estrogen derived from plant sources offering selective actions in tissues and potentially have less impact on breast tissue and lipid levels. However, there is not enough proof that there is a reduction of breast cancer or blood clots.
Both Slynd and Nextstellis are indicated for prevention of pregnancy in women. Since Nextstellis is a COC, it comes with the following exceptions;
· Women >35 yoa who smoke cigarettes
· Women with a history of hormone dependent cancer
· Those with a high arterial thromboembolism risk
· Those with a high deep vein thrombosis risk
· Those with a high pulmonary embolism risk
· Those with a high cardiovascular risk (uncontrolled high blood pressure, recent heart attack)
· Those with severe migraine with aura
· Women with a BMI > 35 as it has not been studied but early thoughts suggest it may be less effective
Compared to other combined oral contraceptives (COC), Nextstellis appears to have lower rates of side effects such as acne, worsening of high blood pressure, weight gain and mood changes but there have not been any direct head-to-head studies to confirm.
As with all oral birth control pills, they do not protect against sexually transmitted infections (STI) and barrier methods must still be used for STI prevention. More on that in a future Ask the Pharmacist column.
How They Compare with Traditional Birth Control Methods
To put Nextstellis and Slynd in context, here is a rough comparison with more established birth control options:
Method Typical Effectiveness* Key Advantages Key Considerations / Risks
Nextstellis – (combined pill, drospirenone + estetrol) ~ 1–2 per 100 women per year (if taken correctly) Modern estrogen, good cycle control, convenience Risks of clotting, not suitable for smokers >35, BMI limitations, typical hormonal side effects, no STI protection
Slynd – (progestin-only drospirenone pill) Very low pregnancy rate when used correctly (Pearl Index ~ 0.2) No estrogen, more forgiving missed-pill window, safer for some women Daily adherence required; possible irregular bleeding; no STI protection Standard combined pills Similar when used correctly (combined ~ Broad experience base, many options, non-Estrogen-related clot risk; adherence
Method Typical Effectiveness* Key Advantages Key Considerations / Risks/ older POPs /
patches / rings 99.7% perfect use; typical use lower) contraceptive benefits (cycle, acne, etc.) issues; side effects; no STI protection
Long-acting methods (IUDs, implants) Among the most effective: <1% per year with typical use “Set and forget,” very low user-failure risk, long duration Insertion required; possible discomfort; side effects depend on type; no STI protection
* “Typical use” accounts for imperfect adherence (missed pills, delays, etc.) and real-world effectiveness tends to be lower than “perfect use.”
Though the oral contraceptives show a high effective rate to prevent pregnancy, very few women practice “perfect use” to maintain that effectiveness. More women are now opting for the peace of mind associated with IUD’s and implants. There is something to be said for not having to contend with the reduced efficacy of being late or missing a dose of their oral contraceptive. However, even though IUD’s and implants are among the most effective at preventing pregnancy, it is important to note that they do not offer any protection against sexual transmitted infections. Practice safe sex and protect yourself by using a condom. For more information on this or any other health related topic, contact your pharmacist.
