Mini-IVF: Is it for me?
When looking for a recipe, we often search the internet or head towards our favorite tried and true cookbook. Usually, we can find a few different options to make the same dish: a low-fat version, a low-carb version, one with gluten-free or dairy-free substitutes. We use our judgement, think about who we are feeding and what their food sensitivities might be, and consider party numbers. Often, we rely on our experience of how we made the recipe in the past. There is always some trial and error involved, and hopefully the end product is a masterpiece and tastes great!
Looking for the perfect IVF protocol can be similar. There are a lot of choices, and finding the ideal recipe for each patient can be tricky. As fertility doctors, we consider the patient’s past treatment cycles, age, egg supply, and prior response, and we use the published data as well as our experience and judgement to pick the best protocol each month. As we tell our patients, sometimes trying out one protocol or another is a learning experience, and together we figure out what works best.
Minimal stimulation, also called low-dose or “mini” IVF, is one of the newer protocols in our recipe book. The idea behind minimal stimulation is that using lower doses of fertility drugs to coax fewer eggs out of the ovary per month could result in better-quality eggs and embryos, thereby resulting in higher pregnancy rates. Now, every IVF patient — and, to an extent, every IVF doctor — is trained to think that more eggs is better! However, recent data suggests that using higher doses of drugs does not necessarily translate to higher pregnancy rates.
In fact, published data has compared high-dose and low-dose IVF protocols, and the results show that there is no difference in pregnancy rates when either protocol is used. This particularly seems to be the case among women with a low egg supply. And the added benefit of milder stimulation is fewer side effects and lower costs for drugs per cycle!
Now, minimal stimulation is not typically a one-cycle option. Because many patients who pursue IVF are older or produce many abnormal embryos, multiple cycles might need to be done — in a process called batching, whereby eggs and embryos are collected over multiple cycles. Sometimes we use PGS (preimplantation genetic sampling) to analyze the genetics of the embryos after a few cycles, and multiple embryos are collected.
Which drugs are used for minimal-stimulation IVF? As with any recipe, this varies from clinic to clinic, patient to patient, and doctor to doctor. Sometimes fertility doctors will use pills alone, such as Letrozole or Clomiphene, and sometimes in combination with gonadotropin injections, such as FSH or hMG, but typically at lower doses, using 150 IU per day rather than 300 or 450 IU.
Usually, the stimulation is still about 9 to 11 days long, and it still involves one or more egg retrievals, but the side effects during stimulation and the egg retrieval procedure might be less painful and better tolerated because fewer eggs are being produced per cycle.
Ask your fertility doctor about whether mini-IVF is an option for you. Just like a good recipe, even though the tried and true choice will often produce a reliable and tasty result, sometimes switching things up can surprisingly have a better effect!