Intra-Uterine Insemination (IUI) and In Vitro Fertilization (IVF)

Intra-Uterine Insemination (IUI) and In Vitro Fertilization (IVF)

Intra-Uterine Insemination (IUI) treats infertile men with a low sperm count. Semen is collected — from the husband or, where necessary, a healthy donor — and, after the woman's ovaries are stimulated to produce more ova, it is introduced directly into the uterus through the vagina using a catheter. From there, the sperm swim on to the fallopian tubes to fertilize an egg naturally, so a normal pregnancy can follow; the technique's whole value is shortening the distance a limited number of sperm must travel.

In Vitro Fertilization (IVF), popularly known as the 'test-tube baby' technique, goes a step further: sperm and eggs are united entirely outside the body, in a laboratory, and one or more of the resulting fertilized eggs are then transferred into the woman's uterus to implant and develop; any spare embryos can be cryopreserved (frozen) for later use. IVF was originally developed for women with blocked, damaged or absent fallopian tubes, but is now used to treat many different causes of infertility. A typical IVF cycle runs through five stages — ovarian stimulation, egg retrieval, fertilization, embryo culture and embryo transfer. Egg retrieval itself is a minor surgical procedure under general anaesthesia, performed 34–37 hours after an hCG (human chorionic gonadotropin) injection, using ultrasound guidance; the retrieved eggs are cleaned of surrounding cells while sperm are separately prepared in a special medium, and roughly 10,000–100,000 motile sperm are needed per egg for fertilization to succeed reliably. The resulting zygote is cultured un …