![]() Figure 3.1
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It has now been 20 years since the pioneering discovery by Patrick Steptoe, M.D. and Robert Edwards resulting in the birth of Louise Brown. To date there have been thousands of healthy children conceived, and born, utilizing the technique of IVF. The first cases of IVF performed in the late 1970′s and early 1980′s were limited to women with fallopian tube obstruction. The techniques have since evolved to assist men who have been considered sterile due to irreparable obstruction such as congenital absence of the vas deferens or poor sperm production. ICSI or intracytoplasmic sperm injection is an advanced form of in-vitro fertilization (test tube). It has been heralded as the single most important discovery in the field of reproductive medicine. With ICSI, only one live sperm need be present to fertilize each egg. Therefore, even men who make very few sperm are now able to father children of their own.
The concept of ICSI is actually quite simple. To understand ICSI we must first review some basic female physiology. The ovary is the female reproductive organ that contains the eggs. A woman is born with all of her eggs which are in an immature state. Normally, each month several follicles develop within the ovary, but one becomes the dominant follicle and releases a single mature egg (oocyte).
In preparation for IVF the woman is given fertility medications to stimulate ovarian follicle production to enable the maturation of more than one egg. The eggs are then retrieved from the ovaries using a thin needle guided by ultrasound. The oocytes are taken to the IVF laboratory where they are prepared for use. Sperm are then collected from an ejaculation or the testicle/epididymis if there is a male factor problem. The sperm are also taken to the IVF lab.
In the IVF lab the oocytes and sperm are placed on a special slide or dish and examined under an inverted microscope. The microscope has a system of two hydraulically controlled micropipettes (very fine glass needles) attached. The movement of the pipettes is controlled by the embryologist via joysticks.
An oocyte is held in place with one pipette while the smaller pipette is used to pick up a single live sperm. This pipette is then manipulated to pierce the oocyte cell membrane and the sperm is injected into the cytoplasm. The DNA (genetic material) of the egg and sperm then recombine and the egg fertilizes. The cell then begins to divide into a two, four, six then eight cell embryo over the course of two to three days. It is at this point that the best quality embryos are placed in the woman’s uterus (womb). If the embryo implants and continues to grow then a pregnancy is established.
Success rates for IVF are reported as fertilization rate, pregnancy rate, and delivery rate. These rates vary based on the woman’s age, cause of infertility, and skill of the laboratory and physicians.



