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Doctor Profile |
Christopher D. Williams, MD
Reproductive Medicine & Surgery Center of Virginia, PLC
Dr. Christopher Williams grew up in Reston, Va. He completed his undergraduate training at the College of William & Mary and received his medical degree from the University of Virginia. Dr. Williams completed his residency in Obstetrics and Gynecology at Carolinas Medical Center and a Fellowship in Reproductive Endocrinology and Infertility at The University of North Carolina. He is a Fellow of the American College of Obstetricians and Gynecologists, and sub-specialty certified in Reproductive Endocrinology and Infertility. Dr. Williams is the author of a fertility book for couples sold internationally, The Fastest Way to Get Pregnant Naturally. He is married and has two boys and a girl.
Egg freezing probably represents the future of IVF. At the present time, IVF often creates excess embryos that are cryopreserved. This has become a contentious political issue during recent years. In reality, most often cryopreservation of embryos is a fortunate event for couples, giving them the opportunity to try to conceive again in the future more cost-effectively. However, at times it creates ethical dilemmas for couples and their caregivers, such as when divorce occurs, when a partner dies, or when couples no longer wish to use their embryos. A novel strategy utilizing egg freezing would involve fertilizing only a few of the "fresh" eggs obtained from an egg retrieval to create one or two embryos. These would be transferred into the woman's uterus. The additional eggs would be cryopreserved. For future attempts to conceive, eggs could be thawed a few at a time and then fertilized to create one or two more embryos for transfer to the uterus. This would obviate the need to create and store excess embryos and revolutionize how IVF is performed.
Intracytoplasmic Sperm Injection (ICSI)
Prior to the early 1990s a man needed a minimum of a few million sperm in the ejaculate to allow a reasonable number of eggs to fertilize during IVF. Surprisingly, about 50,000 sperm per egg are required for normal fertilization rates to occur. In cases where the sperm count was too low to attempt IVF, the only other alternative was to use donor sperm. A diagnosis of severe oligospermia represented a large percentage of infertile couples for which IVF was not a good option.
In the early 1990s a major breakthrough occurred. A Belgian team of researchers perfected a method to inject a single sperm directly into a single egg using a microscopic needle. This technique was termed intracytoplasmic sperm injection, or ICSI. Surprisingly, ICSI resulted in normal fertilization rates. It was an incredible innovation that allowed men with even a few sperm in the ejaculate, or sperm from a testicular biopsy, access to IVF. Success rates were similar to couples who had eggs fertilized naturally. This turned out to be probably the greatest single technical advance the field of IVF has experienced.