Ella, a brand name for the medication ulipristal acetate, is a highly effective form of emergency contraception available by prescription. It can prevent pregnancy for up to five days (120 hours) after unprotected intercourse. Its mechanism offers a longer window of opportunity compared to some other emergency contraceptive pills.
The Role of Progesterone and Ovulation
Progesterone, a hormone produced by the ovaries, is crucial in preparing the uterus for pregnancy and plays a key role in regulating the menstrual cycle, including ovulation. Ovulation, the release of a mature egg, is triggered by a surge in luteinizing hormone (LH). Progesterone's activity is involved in the timing of this process, and Ella works by interfering with this hormonal signaling.
How Ulipristal Acetate Delays Ovulation
Ulipristal acetate is a selective progesterone receptor modulator (SPRM). It interacts with progesterone receptors, preventing progesterone from carrying out its normal functions, which disrupts the body's preparation for ovulation. This action delays or prevents the LH surge, thereby postponing egg release.
- Effectiveness near Ovulation: Ella is effective even if taken when the LH surge has started.
- Blocking Follicle Rupture: It has been shown to block the release of the egg from the follicle.
- Potential Endometrial Changes: Ulipristal acetate might also cause changes to the uterine lining, potentially making implantation more difficult, though this is a secondary and debated effect. Ella does not terminate an existing pregnancy.
Ella vs. Plan B: A Comparison of Mechanisms
Choosing between Ella and Plan B involves considering their different mechanisms, timing, and effectiveness relative to body weight.
| Feature | Ella (Ulipristal Acetate) | Plan B (Levonorgestrel) |
|---|---|---|
| Active Ingredient | Ulipristal Acetate (SPRM) | Levonorgestrel (synthetic progestin) |
| Primary Mechanism | Delays/inhibits ovulation by blocking progesterone receptors, effective even during LH surge. | Delays ovulation by preventing the LH surge. |
| Effective Window | Up to 120 hours (5 days). | Up to 72 hours (3 days). |
| Effectiveness near Ovulation | Highly effective. | Less effective after LH surge begins. |
| Availability | Prescription only. | Over-the-counter. |
| Body Weight Impact | More effective than Plan B for higher BMIs, but effectiveness decreases above 195 lbs. | May be less effective for individuals over 165 lbs; not recommended for those over 195 lbs. |
What to Expect After Taking Ella
Common side effects of Ella include headache, nausea, abdominal pain, and menstrual cramps. Your next period may be altered in timing or flow. If your period is significantly delayed, take a pregnancy test. Ella can interact with hormonal birth control, so it's important to use a barrier method until your next period.
Conclusion
Ella, through its action as a selective progesterone receptor modulator, primarily prevents pregnancy by delaying or inhibiting ovulation, even close to the expected time of egg release. This mechanism contributes to its high effectiveness and longer use window compared to levonorgestrel options. Being a prescription medication, its use can be discussed with a healthcare provider to address individual circumstances and potential interactions. The National Institutes of Health provides detailed scientific information on ulipristal acetate.
Post-Ella Contraception Plan
After taking Ella, it is important to plan for ongoing contraception:
- Wait 5 Days: Do not start hormonal contraception for five days after taking Ella.
- Use Barrier Methods: Use condoms or another barrier method for contraception until your next period.
- Restart Hormonal Method: After the five-day wait and using barrier methods, you can restart your hormonal birth control. Continue using a barrier method for another seven days.
- Consider LARCs: Discuss long-acting reversible contraceptives like IUDs with your provider for highly effective ongoing prevention.
Understanding how Ella works is vital for its proper use as emergency contraception.
