IVF – in vitro fertilization
IVF is a technique involving the fertilization of eggs by sperm outside the body. The term literally means 'fertilization in glass' - hence the commonly used description 'test-tube baby' technique. IVF treatment is made up of a number of several procedures usually referred to as a 'treatment cycle'. The cycle consists of multiple steps.
First of all, the woman is prescribed a drug which suppresses the release of the hormones responsible for the production of an egg. This is necessary in order to establish a 'base' from which to start ovarian stimulation. Ovarian stimulation - Once the base has been established, ovarian stimulation commences, which takes the form of a daily intra-muscular injection. Stimulating the ovaries this way should produce several eggs to ensure that there are enough for fertilization. Regular monitoring of the effects of the drugs on the ovaries is undertaken through ultrasound scans and blood tests.
Once the ultrasound scan and blood tests indicate that there are a sufficient number of mature follicles, a final injection is administered to ensure the ripening of the eggs in preparation for the egg collection. Eggs are collected from the ovaries through the vagina using a fine needle under ultrasound guidance to remove the eggs from the follicles. This is performed as a day-case in our Day Care Unit, typically under sedation. On the day of the egg collection, the male partner is required to produce a semen sample at the center. The sample is then prepared in the laboratory to extract the most motile sperm. When all the eggs have been collected, they are put in a dish with the prepared sperm and incubated in the laboratory. Approximately sixteen hours later, the embryologist will check to see whether fertilization has occurred.
If fertilization was successful, usually two of the embryos are transferred directly into the uterus two days after the egg collection. The embryos are transfer through the vagina and cervix using a fine catheter. Usually this procedure is painless. A pregnancy test should be carried out fourteen days after the transfer. If the result is positive, an ultrasound scan is recommended two or three weeks later to check the embryo is alive and situated in the uterus.
GIFT (Gamete Intra-Fallopian Transfer)
GIFT is an early, and very simple ART (Assisted Reproductive Technology) technique. The success rate with GIFT is higher than with standard IVF (in vitro fertilization), but GIFT can only be performed if the patient has healthy fallopian tubes and adequate sperm. Otherwise, IVF should be mandated.
GIFT stands for "Gamete Intra-Fallopian Transfer." Gametes, the female's eggs and the male's sperm, are placed via catheter directly into the patient's fallopian tubes. This usually involves a minor surgical procedure which allows you to go home the same day. With GIFT, fertilization occurs inside the patient's body, and mimics the way a normally fertilized egg would begin its journey to the uterus for implantation.
How Does GIFT Work?
In a fertile couple, pregnancy begins with the release of an ovum (egg) from the woman's ovaries. The egg enters the fallopian tube where it meets with sperm that have traveled there, following intercourse, from the vagina. The sperm then fertilizes the egg in the fallopian tube.
The fertilized egg, now called an embryo, begins to divide and in four days, contains many cells. At this time, the embryo moves from the fallopian tube to the uterine cavity where it "floats" for another two days. The embryo then implants in the uterine wall, and the pregnancy starts.
The GIFT technique allows the eggs to fertilize and develop in the natural environment of the fallopian tube, and then to make their way to the uterus for implantation according to a healthy timetable. In contrast, in vitro fertilization (IVF) places fertilized eggs directly into the uterus. One of GIFT's major advantages over IVF is that the technique relies to a far greater degree on the body's natural processes and timetable to produce pregnancy, and is acceptable to religious patients who avoid the more embryo invasive technologies.