There are four steps involved in the standard in-vitro fertilization (IVF) procedure: Ovarian Stimulation, Egg Collection, Fertilization, and Implantation.
The IVF procedure involves stimulating the ovaries to produce a more significant numbers of eggs than normal. Doctors then collect the female eggs and manually combine them (or one) with a male’s sperm to create an embryo for fertilization. The healthy embryo is then re-implanted into the female’s uterus for pregnancy.
Step 1: Ovarian Stimulation
Ovarian stimulation, also called controlled ovarian hyperstimulation, is the process of using hormones to stimulate the ovaries to release more eggs than normal. Treatment usually starts on the third day of the patient’s menstruation cycle, when she is injected with a follicle stimulating hormone(FSH), one of the fertility drugs used in IVF. The FSH, (generally a gonadotropin-releasing hormone) does not improve the quality of the ovarian reserve but increases the number of oocytes that can be collected. Patients usually require an average of ten days of FSH injections. Ovarian stimulation allows the doctors, using an ultrasound, to track the size and number of follicles in the uterus. This ensures they are mature when removed.
Step 2: Egg and Sperm Collection
When oocytes are matured, doctors use a trans-vaginal technique to retrieve the eggs from the ovaries. Doctors insert an ultrasound-guided needle that draws the ova from the ovaries and collects them in a laboratory dish. Doctors generally obtain between 10 and 30 eggs. Doctors then examine the oocytes to determine the healthiest and most likely to successfully fertilize. The procedure takes no more than thirty minutes and patients receive a local or general anesthesia.
Meanwhile semen is prepared for fertilization. The male partner will either provide his sperm or donated sperm will be retrieved used if the male partner has a severe male infertility factor or if the patient is lacks a male partner. Through a process called ‘sperm washing,’ doctors separate the sperm from the semen.
Step 3: Fertilization
The chosen oocytes are placed together with the prepared sperm in a laboratory dish. In specific cases with a low sperm count, a single sperm may be injected into the oocyte through intracytoplasmic sperm injection (ICSI). Once fertilized, the egg begins to divide, forming an embryo. The cells divide until six to eight cells have been formed before returning to the mother’s uterus. The cell division takes approximately 48 hours.
If patients risk passing a genetic disease onto their unborn children, they may wish to undergo an pre-implantation genetic diagnosis procedure. IVF with PGD can also be used for gender selection.
Step 4: Embryo Transfer
Embryo Transfer is the last step in the IVF procedure. Doctors analyze the embryos to choose the ones most likely to facilitate a pregnancy. The chosen embryo(s) are then implanted into the uterus through the vagina and cervix using a catheter. With IVF, the embryo bypasses the fallopian tubes, as opposed to in a natural pregnancy. The patient will continue taking hormones for the next two weeks in order to help the embryo attach to the uterine wall and grow (implantation).
Depending on the mother’s age and specific circumstances, as many as three embryos may be transferred. However, most clinics seek to reduce the number of multiple pregnancies so the number of transferred embryos will be carefully discussed. Multiple pregnancy is one of the risks and side effects of IVF. If healthy embryos are leftover from a patient’s IVF treatment, doctors may ask the patient to donate the embryo to other couples struggling to conceive.
Successful pregnancy rates from IVF treatment have risen significantly over the previous years.
The information on this site is not a substitute for diagnosis or treatment from a licensed medical practitioner. If you are experiencing a serious medical condition call your local emergency services or your doctor.