Understanding IVF stimulation protocols

Understanding IVF stimulation protocols

IVF Stimulation protocols

The first IVF procedure which was successful was performed in 1978 without the use of any drugs. However this method was done away with considering the low success rate. With innovation in technology related to fertility treatment the advancement of successful pregnancy improved after the transfer of one embryo inducing the doctors to reintroduce the earlier model of “natural cycle IVF” with the retrieval of one oocyte.

The natural cycle of IVF carries advantages as it is simple, puts lesser stress on the patient, can be easily conducted at the clinic and repeated every month. Furthermore, as the method does not use any stimulation drugs the risk of ovarian hyperstimulation syndrome (OHSS) is thwarted. But there is a constraint as the patients are usually in the age bracket below 34, as with older patients the success rate decrease.

It also carries with it disadvantages such as the success rate with pregnancy is low post the transfer of one embryo. There is also a risk of cancellation attributed to reasons such as poor quality embryo, premature ovulation and fertilization failure. Also it demands constant monitoring during egg retrieval and frequent blood tests to oversee the increase in LH surge.

Objective of IVF Protocols

The aim of a good in-vitro fertilization ovarian stimulation is to obtain more or less eight to fifteen quality eggs. The success rate of an IVF cycle is dependent on the number of eggs retrieved. There are quite a few ovarian stimulation medication protocols which helps to stimulate or pump the ovaries to make enough follicles and eggs. As without the use of stimulating medications and drugs, the ovaries naturally make and release only one mature egg per menstrual cycle every month. The frequently used stimulation treatment involves injecting of follicle stimulating hormone – FSH.

One protocol may be preferred over another considering the situation.

  • As ovarian stimulation is a complex process, and there exist many inconsistencies considering the patients who have a significant impact on the final result.  Under a natural cycle, numerous oocytes start to grow; the precise number of eggs relates to various factors which entails the age, hormonal “status”, and the health of the ovaries of the patient.
  • As a known fact, eggs reduce with age as is the case of older patients, hence they will be expected to develop lesser number of eggs than younger patients.  Likewise, patient’s ovulation is affected  as a result of abnormal hormones level such as prolactin, thyroid stimulating hormone (TSH), and testosterone, therefore they will not respond to stimulation as well as in case of normal hormonal levels.
  • Lastly, patients who have had ovarian surgery in the past or those with active ovarian disease (endometriosis or ovarian cysts) are bound to produce lesser number of eggs as they otherwise could.

Similarities exists amongst IVF Protocols

  • Furthermore, there exist four additional classes of medications that build the foundation of the stimulation protocol:
  • As the eggs are in various stages of development in a typical case of a reproductive woman, to undergo stimulation without BCP’s would result only in few eggs to develop. This has been proved by various experts that BCPs actually help the eggs   synchronize the development of the eggs, so that when the course of the pills is done and the stimulation medications are commenced, higher number eggs are ready to respond.  As a consequence more number of mature oocytes is available at the time of retrieval, boosting the chances of fertilization in comparison to women who start stimulation directly.
  • Similarities too exist between different commonly used stimulation protocols, considering there are many differences, such as most modern protocols commence within 3-4 weeks of birth control pills (BCP) and this also supported by a very good reason too.

1. Gonadotropins (or other medications) supports the eggs to develop

2. A gonadotropin releasing hormone (GnRH) analog to check premature ovulation

3. Medication to help the eggs to mature

4. Progesterone to sustain the lining of the uterus post embryo transfer

The way these medications are directed identifies the actual stimulation protocol.

Example of different kinds of commonly used ovarian stimulation protocols:

  • Luteal Lupron protocol also known as  “long Lupron”, or Long Down-Regulation Protocol
  • Antagonist protocols which entails the use of the GnRH antagonist medications
  • Flare and micro-flare protocols, also called short Lupron protocols/ Poor Responder
  • Protocol, is helpful in  patients with a reduced response to ovarian stimulation

Goal of a good in vitro fertilization ovarian stimulation

The goal of a good in vitro fertilization ovarian stimulation is to obtain more or less eight to fifteen quality eggs. At the same time overstimulation of ovaries needs to be checked as it causes discomfort and at times leads to ovarian hyperstimulation syndrome, OHSS. Moreover the stimulation should not be unsatisfactory resulting in only few eggs, in such a situation more eggs could be obtained with increased dosage of the drugs. Although in rare cases invitro fertilization can be successful with a few number of eggs but success rates are considerably elevated when more eggs are recovered.

To conclude, once a patient is subjected to ovarian stimulation it is the responsibility of the infertility expert doctor to design an appropriate medication procedure and dose regime. It also involves actively monitoring of patient’s stimulation progress, so that the medication dose is tuned as per the requirement.