In Vitro Fertilization(IVF):
This is a grossly misunderstood and misinterpreted term by the lay public. IVF is also being erroneously marketed as a sure-shot solution for infertility. Therefore people think that IVF gives 100% results and this is totally wrong information. This leads to unnecessary and futile financial and emotional stress for the patient.
Let us clear the concepts about IVF. In Vitro Fertilization means fertilization in the laboratory. This indicates that both sperm and ova are removed from the body and fertilization is allowed in the laboratory under the conditions similar to the body. Once fertilization occurs and the embryo is formed, it is transferred back into mother’s womb. Therefore it is important to remember that if the female is not given anaesthesia, if the ova are not removed from the female’s body, it is not IVF.
The simplest way to explain the IVF procedure is:
- The female’s natural hormones are totally neutralized by GnRh analogues.
- Then ovaries are stimulated by high doses of gonadotrophins to produce multiple follicles.
- When these follicles become mature, these are picked out of the female’s body and are mated with the sperm.
- Fertilization occurs in the body and embryos are allowed to grow for 2 -5 days.
- Then these are replaced back into the uterus.
The patient is down regulated using GnRh analogues from day 2 of the cycle. Usually, 3-4 ampoules of gonadotrophins per day are started and ultrasound is done on the fifth day of stimulation to assess the size of the follicles and endometrial thickness.
If at this stage the follicles are of < 10mm in size, the dose of rFSH is increased from 3 to 5 or 6 ampoules as required. Older patients may require higher doses. Again the patient is examined by ultrasound and the growth of the follicles is monitored until at least one follicle of 18mm and two follicles of 16mm are seen. Assessment of the follicles and endometrium is done by color Doppler and 3d ultrasound. Then trigger is given for follicular rupture and ovum pick up is done exactly after 34-36 hours.
Ovum Pick up:
Ovum picks up is done under anesthesia with full aseptic technique. This procedure is done under transvaginal ultrasound guidance and all the follicles are aspirated into test tubes and are directly transferred to the laboratory. The whole laboratory procedure is done under laminar airflow. Ova that are retrieved from the follicles are identified, cleaned and are put with the sperms in the media for fertilization in a CO2 incubator. CO2 incubator maintains a specific level of CO2, humidity, and temperature, similar to that in the body. The media helps to maintain the pH and nourishes the growing embryo. Embryo development is assessed from time to time until these are replaced back into the mother’s womb. This may be done on the 3rd or 5th day of the pickup.
This as mentioned is done on the 3rd or 5th day after ovum picks up. This is done under transabdominal ultrasound guidance with a specialized cannula and with total aseptic technique. The patient is allowed to rest for 15-30 minutes after the procedure.
The luteal support is given by vaginal tablets or intramuscular injections of progesterone from the day of hCG and urine pregnancy test or β hCG is done on the 12th day of the transfer to know whether pregnancy has occurred or not.
It is important to understand that everything is under control until embryo transfer, but the process of implantation is very crucial. This process is still not completely understood by science. The failure of IVF is due to implantation failure most of the time.
Intracytoplasmic Sperm Injection (ICSI):
For the patients with a very low sperm count that cannot be improved by the medical line of treatment, ICSI is the solution. Instead of putting the ova and sperms together and allow fertilization, in ICSI a single sperm is injected into the ovum to facilitate fertilization. Where about one lac sperms are required per ovum for IVF, for ICSI only one sperm is required for one ovum. For ICSI sperms can also be aspirated from testis or epididymis if the patient is azoospermic.
When husband’s semen is not available at the time of insemination, either due to unavailability of husband or due to inability of husband to produce semen, in these patients, semen may be collected at other times and can be stored in liquid nitrogen at extremely low temperatures and this is known as cryopreservation of semen. The semen can be thawed whenever required and can be used.
Embryos can also be frozen and stored, when many embryos are formed or when good embryos are available but the endometrium is not of good quality.
When female is old, or her ovaries are aged and cannot produce ova, ova can be borrowed from another female. This is known as ovum donation. These ova can then be fertilized by the sperms of a patient’s husband and transferred into the patient’s womb.
For those couples in whom sperms and ova both are not available, instead of only ovum, the whole embryo is taken as a donation and then transferred into the female partner’s womb.
For the females whose uterus is absent, but the ovaries are active, or the uterus, because of some disease is not capable of holding the pregnancy till the end, for these patients, the embryo created by their own ovum and partner’s sperms can be transferred into some other female’s uterus. This is known as surrogacy. In most simple words, it is like taking the uterus on rent.