For infertile couples in which the woman has blocked or absent fallopian tubes, or the man has a low sperm count, in vitro fertilization (IVF) offers the chance of biological parenthood to couples.

In IVF, eggs are surgically removed from the ovary and mixed with sperm outside the body in a Petri dish ("in vitro" is Latin for "in glass"). After about 40 hours, the eggs are examined to see if they have become fertilized by the sperm and are dividing into cells. These fertilized eggs (embryos) are then placed in the women's uterus, by-passing the fallopian tubes.

IVF has received a great deal of media attention since it was first introduced in 1978, but it actually accounts for less than five percent of all infertility treatment.

Does in vitro fertilization work?

Yes. IVF currently accounts for about 98% of ART procedures, with GIFT, ZIFT and combination procedures making up the remainder. The average live birth rate for IVF in 1998 was 29.1% per retrieval; a little better than the 20% chance in any one month that a reproductively healthy couple has of achieving a pregnancy and carrying it to term.

Is in vitro fertilization expensive?

Yes it is. Like other extremely delicate medical procedures, IVF involves highly trained professionals with sophisticated laboratories and equipment, and the cycle may need to be repeated to be successful.