What is in vitro fertilization?
IVF involves retrieving eggs from the woman and fertilized with the husbands semen in a petridish simulating a natural fertilization process.
The IVF process involves
- Stimulating growth of multiple eggs
- Egg retrieval
- Fertilizing the eggs with husband’s sperm
- Embryo transfer into the uterus
Who should undergo treatment with IVF?
- Blocked or damaged fallopian tubes.
- Low sperm count for the husband.
- Poor sperm motility.
- Several failed IUIs (intra uterine inseminations)
- Advanced maternal age above 35 years
- Reduced ovarian reserve
- Unexplained infertility
How does IVF improve fertility?
In essence, we are compressing several months of “natural” attempts into one cycle . By transferring fertilized embryos directly into the uterus we are bypassing cervical and tubal causes of infertility.
A normal woman only produces one egg per cycle, in an IVF cycle we are able to produce several eggs per cycle.
The best quality embryos are selected and depending on the age of the patient we transfer 2-4 embryos per cycle.
All remaining embryos are frozen for the next cycle.
Effectively bypassing all cervical factors of infertility and directly implanting the embryos into the uterine cavity.
Embryo Transfer :
Embryo transfer is the most important step in the IVF procedure, it requires expertise and sufficient skill. Depending on the age of the patient 1-3 embryos are transferred into the uterine cavity using special catheters. The embryo transfer is performed under ultrasound guidance. This is a completely painless procedure and does not require any anesthesia.
After this procedure, you will be asked to lie down for about 2 hours.
After embryo transfer, you will be prescribed medications to maintain the pregnancy growth.After 3 days of rest, you can go back to your normal routine, although strenuous workouts, sexual intercourse should be avoided.
How is IVF performed?
Fertility drugs are given to stimulate ovaries to develop several mature follicles.There are several protocols followed for ovarian stimulation, the most commonly used ones are mentioned below.
In order to maximize success rates within IVF, we want a good number of high-quality eggs from the woman. We generally try to get about 10-18 eggs at the egg retrieval procedure.
GnRH agonists are started from day 21 of previous menstrual cycle. Gonadotropins are started from day 3 of current cycle.Gonadotropin dosage is altered depending on the growth of the follicles. Once enough follicles have reached 18-20 mm in size, a HCG injection is administered to mature the follicles.
Gonadotropin stimulation is started from day 3 of cycle.GnRH antagonists are started after the dominant follicle reaches 14 mm in size and continued until the dominant follicle reaches to 18-20 mm in size. At this point a HCG injection is administered to mature the follicles.
GnRH agonists are started on the 1st day of the cycle followed with gonadotropin stimulation on day 3.
As soon as the follicles are deemed ready for collection, an HCG injection is given.The eggs are collected in the operation theatre under anesthesia.This complete process takes about 15 – 30 minutes depending on the number of follicles.You will be able to go back home the same day.
The sperm sample is obtained either on the same day or a frozen sample (collected earlier) is thawed and utilized.
We mix the collected oocytes and the sperm in a petridish in culture media. The eggs are checked the next morning for evidence of fertilization.
The embryos thus formed are incubated for 3 or 5 days depending on the type of embryo transfer.During this time, the patient is started on progesterone therapy to ready the endometrium for implantation. Once the endometrium is ready for implantation (confirmed by ultrasound), the embryo transfer is performed.
A brief idea about embryo grading:
Most clinics “grade” each embryo using one of many scoring systems. Unfortunately, there is no agreement at all as to which system to use.
Children born from low-grade embryos are just as competent as those born from high-grade embryos. The only difference seems to be with the chance for the embryo(s) to result in a pregnancy.
* Cell number
* Embryos should be at 2 to 4 cells at 48 hours after egg retrieval and preferably about 7 to 10 cells by 72 hours.
* Cell regularity
* The cells within the embryo should be relatively regular in shape and size.
* Here, the embryo’s cells have broken off and are now separate from a portion of the cell. It is preferable to have little or no fragmentation.
Other aspects of the microscopic appearance of the embryos are also noted including the presence of vacuoles, granularity, the thickness of the outer shell, etc.
In an ideal scenario :
By 48 hours (“day 2”), the embryos must be to at least 2 cells. We prefer that at least some of them are at the 3 or 4 cell stage by then.
By 72 hours (“day 3”), we like to see at least 6 cells – and preferably some at about 8 cells. We have seen babies that came from 4 cell embryos on day 3, but chances for pregnancy increase significantly with increasing cell number.
The highest chance of implantation will be achieved by embryos with very minimal fragmentation, regular in appearance and higher cell numbers.
Although looking at the embryo under the telescope can give us a reasonable prediction of the chances of success for implantation, there are no one standardized means to measure the quality of the embryo and it varies from lab to lab.
It is what’s within the embryo that is most important, the DNA potential of the embryo to implant into the uterus.
Unfortunately, it is impossible to predict the true genetic potential of the embryo to implant unless we perform a Pre- implantation genetic screening test (PGS) on the embryo.
When do I take a pregnancy test?
A pregnancy test can be done 2 weeks after the procedure. We recommend a b- HCG blood test as it is more sensitive and gives a more accurate result than a urine pregnancy test.
What happens to the remaining embryos?
All viable embryos will be frozen.
If embryo transfer is not possible in the current cycle or embryo transfer is unsuccessful, the frozen embryos will be transferred the next cycle.
If implantation is successful, the choice of what happens to the remaining embryos is at you and your partner’s discretion.