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June 9, 2022

Long Protocol and Short Protocol

Which will I be put on and what is the difference?




What are Long and Short Protocols?


When you decide that the time is right for you and your partner to start fertility treatment, a phrase that you will no doubt start to read about is ‘long protocol and short protocol’. Long and short protocols are the two most common terms for types of ovarian stimulation used in IVF to collect a patient’s eggs.


This article aims to outline the difference between the two protocols so that you are able to go into your doctor’s consultation with a little more understanding of what your treatment plan will entail.


Firstly, the phrase ‘protocol’ is used to describe the treatment plan your doctor at HSFC will place you on. Depending on your medical history and other factors such as AMH, HSFC will tailor your protocol to your specific fertility needs. HSFC design all treatment plans to be tailored to suit our patient’s, to ensure the best and safest outcomes.




Long Protocol Vs Short Protocol?


Long Protocol


Long Protocol, otherwise known as  GnRH agonist long protocol, has a duration of 4-5 weeks.  A long protocol means that you start your medication on the 21st day of your cycle. This is known as ‘down regulation’. The first medication you take will suppress ovarian function and make your ovaries inactive. Once ovarian function has been suppressed, typically after 10-14 days, you will start the second set of medication, called gonadotrophins (typically FSH or hMG). Gonadotrophins are administered for around 12-14 days. Gonadotrophins stimulate growth of the follicles in your ovaries, ready for egg collection. With HSFC, you should expect internal scans every 3-4 days during this phase so that we’re able to monitor the progress of the medication on your ovarian follicles.



Short Protocol


Short Protocol, also known as GnRH antagonist short protocol, has a duration of 2-3 weeks. In contrast to the long protocol, the short protocol usually consists of between 10-12 days of medication before egg collection. You will start with Gonadotrophins (FSH or hMG) and take these for approximately 10-12 days. As there is no suppression of ovarian function, after your follicles start to grow, ovulation Much like long protocol, you should expect internal scans every 3-4 days during your stimulation phase.


Short protocol is currently the preferred protocol as it does not suppress the body’s natural function, is shorter (fewer injections), works well in nearly all patients and has less risk of OHSS (ovarian hyper stimulation syndrome).


In both protocols, you will require a final trigger injection (or injections) to induce final maturation of eggs and release from the follicle wall, essentially inducing ovulation. The trigger(s) must be timed precisely so that the eggs are mature and can be collected during the egg collection procedure. Typically, the trigger(s) is administered around 36 hours prior to the egg collection.



Is one protocol better than the other?


Long protocol was the first protocol and short protocol was developed later. Initially, long protocol appeared to provide better outcomes, however, we as our experience with short protocol improved, studies have shown there is little difference in clinical outcomes, except that short protocol is less prone to OHSS.


At Harley Street Fertility Clinic, we tend to use a state of the art short protocol, with pre-cycle priming (to synchronise follicular development), mixed gonadotrophins (FSH + hMG) to provide optimal FSH/LH ratios with dual trigger to maximise egg maturity and number.


Your doctor will choose the best protocol for you based on your history and prognosis. Remember, there is no one size fits all in IVF. Ovarian stimulation should be tailored to the individual, i.e. made bespoke, for best results.


What next?

Being given your protocol treatment plan is often the first step in IVF journey and can feel a little overwhelming. Be sure to ask your HSFC doctor if you have any further questions about your protocol or what to expect.


To start your fertility journey, feel free to contact us today.