In vitro fertilization is a procedure used when there is a very small probability of a sperm fertilizing an egg or when the woman’s oviducts are blocked. Here it is how the procedure works:
The process consists in: ovulation induction, egg retrieval, insemination, fertilization, embryo transfer, pregnancy testing.
Before beginning the egg retrieval the woman is injected with some medications in order to stimulate the egg development.
The egg retrieval procedure is very important for the in vitro fertilization treatment.
During the egg retrieval process a woman’s eggs are extracted from her ovaries in order to be fertilized later with sperm provided from a sperm donor.
The following step after the egg retrieval the healthy eggs are mixed with sperm and they are monitored until the fertilization takes place. After the fertilization the next treatment step is the embryo transfer. Embryo transfer can be performed after 2-3 days after that depending on the woman’s age and the number of embryos.
The embryo transfer can be splitted in two categories:
- the transfer of embryos 3 days after the egg retrieval
- blastocyst transfer: it takes place after 5 days of culturing when the embryos reach the blastocyst stage. At this point is easier to choose the healthy embryos to be transferred to the uterus.
Frozen embryo transferis a new type of infertility treatment. Patients who undertake the in vitro fertilization treatment may choose to freeze the extra embryos remained after the procedure in order to use them in an ulterior IVF treatment in case the current one doesn’t succeed. The frozen embryos can be transferred into the uterus later. The operation of embryo freezing is also known as embryo cryopreservation and is a way of beating the biological clock.
Pre-implantation Genetic Diagnosis is performed before the implantation in order to establish if there is a risk of transmitting a genetic disease to the child. If that is the case the entire process could be terminated to avoid the abortion. However not all genetic diseases can be diagnosed using this technique. The causes of a genetic disorder could be linked to chromosomal abnormalities depending on the sex or could be an abnormality caused by a single gene.
Implantation failure is a part of the in vitro fertilization procedure that is not very well understood because patients succeed to produce healthy embryos but at the implantation phase things go wrong for inexplicable reasons.
It is defined as the embryo’s failure to implant during the IVF cycle, but not all the specialists agree with this definition. Some of them consider that implantation failure represents the failure of achieving a pregnancy after several IVF cycles. Other doctors compare the number of embryos which were transferred with the number of treatment tries.
The success rate of IVF is very difficult to establish and is different from one IVF clinic to another. The success rate depends on what basis is calculated. Some clinics, for advertising reasons, say that their IVF success rate is very big but they don’t mention how was this calculated, if they take into consideration just a successful implantation or an ongoing pregnancy or the actual delivery.
Each step of the in vitro fertilization procedure has its specific risks: Superovulation, HSS-Ovarian Hyperstimulation Syndrome, Retrieving the Oocytes.
At the beginning the patient receives a treatment based on hormones for a period of 10 days in order to determine the woman’s ovaries to release more than one egg during the ovulation period. It is expected that the ovaries can produce about 20 eggs as a result of hormone administration. There are two possible ways of collecting the eggs: one of them is by inserting a needle in the vagina and the other one is by making a slight incision in the abdomen. Afterwards the eggs are put into a recipient where they are combined with a specific number of sperm.
If the eggs can’t be fertilized because the sperm aren’t able to reach to them, then each egg is injected with a sperm using the microscope. Once the fertilization takes place after a couple of days the fertilized eggs can be implanted into the uterus. The number of implanted eggs is decided taking in consideration a series of factors. From now on the woman’s body is adjusting and takes care of the embryos.
For ensuring a succsseful pregnancy more than one embryos are implanted into the uterus,but this can lead to multiple births thet can affect the helth of the babies already conceived. Studies show that 10-25% of women who undergo in vitro fertilization procedure have twins. The chances of success with the IVF procedure can’t be predicted because a large number of factors are involved. What is sure is that the success rate is bigger if the female is younger.