Almost every day, someone asks: “Doctor, which protocol should I use? Please give me the best ovarian stimulation plan!” Yes, this is also the most frequent question doctors think about every day. When making each ovarian stimulation protocol, doctors do so with hope, expecting the follicles to grow smoothly and achieving the ideal number of eggs (not too many to avoid ovarian hyperstimulation syndrome; not too few in case it’s not enough). In fact, ovarian stimulation is both a science and an art—it’s not only about the right quantity but also about good quality. Therefore, ovarian stimulation is the most crucial and important step in the entire IVF process because without high-quality eggs, everything else becomes irrelevant.

What are the commonly used ovarian stimulation protocols?

  1. Antagonist Protocol
    This is the most commonly used protocol in the world, especially in developed countries like those in Europe and America.
    Characteristics: The antagonist protocol makes use of the woman’s own FSH and LH, so it requires fewer medications and has a lower incidence of ovarian hyperstimulation syndrome (OHSS).
    Applicable Group: It can be used for various groups, especially those with a high ovarian response.
  2. Long Protocol
    This was the most commonly used protocol in the early stages and is now divided into luteal phase long protocol and follicular phase long protocol.
    Characteristics: Regardless of the type, it requires a longer treatment period.
    Applicable Group: It can be used for various groups.
  3. Ultra-long Protocol
    Characteristics: The ultra-long protocol takes 3 to 4 months, requires 2 to 3 injections of control medication, and then ovarian stimulation drugs are injected. In most cases, 8 to 15 eggs are retrieved.
    Applicable Group: Mainly used for women with endometriosis, fibroids, or those who need precise timing.
  4. Mild Protocol
    Characteristics: The mild protocol has a shorter treatment time, similar to the antagonist protocol, and does not require preparation in the previous cycle. Fewer injections are needed, but embryo transfer is generally not recommended within the same cycle; embryos are frozen for transfer in the next natural cycle as Clomiphene or Letrozole might affect endometrial growth during the current cycle.
    Applicable Group: It can be used for various groups.
  5. Micro-stimulation and Natural Cycle Protocols
    Characteristics: Micro-stimulation and natural cycle protocols result in high-quality eggs with better utilization, lower cost, and fewer complications, but they have a high cycle cancellation rate and lower pregnancy rates per transfer.

    • Micro-stimulation Protocol: Treatment duration is similar to the mild protocol. The doctor will decide on medication based on the ovarian condition and hormone levels during the patient’s menstrual period.
    • Natural Cycle Protocol: Relies completely on the woman’s natural cycle, with no ovarian stimulation medications used.
      Applicable Group: Commonly used for older women, those with poor ovarian function, or those who have failed multiple IVF attempts.
  6. Short Protocol
    This protocol is rarely used now due to its lower pregnancy rate. I haven’t used the short protocol for 5 years, so I won’t introduce it here.

How can we provide you with the best protocol?

Faced with multiple options, doctors base their choices on industry consensus, clinical experience, and continuous learning from the latest international developments. By considering factors such as the woman’s age, ovarian function, response to medications, and previous treatment outcomes, the doctor will select the most appropriate protocol for each patient. The goal is to strike the best balance between effectiveness, safety, cost-effectiveness, and the ideal success rate.

The doctor’s goal in formulating the treatment protocol is: Based on standardization, to personalize the protocol by considering the patient’s overall health, ovarian status, and the couple’s requirements, aiming for an individualized ovarian stimulation plan. For challenging cases, older women, and patients with poor ovarian function, I carefully research and deliberate, hoping every patient will have the chance to successfully conceive!