Wednesday, May 12, 2010

Embryo Banking: Improving Fertility Options for Women

A trend has emerged where more and more couples are choosing to delay having children because of financial and career-related reasons. For a woman, such a decision carries with it an ever present risk that when she ultimately decides to have a baby, she might find herself unable to conceive.

It is an undeniable fact that a woman’s fecundity (the ability to conceive per month of trying) declines in her mid 30’s and then falls off precipitously after 40. Unfortunately, most women/couples do not realize that there could be a price to pay for delaying starting a family. Clearly, aspiring parents need to understand this reality so that they can make informed choices when it comes to planning their family.

Upon becoming aware of the impact of the biological clock, many women/couples become desperate and look to in-vitro fertilization as a solution. For women approaching their 40’s, a achieving a pregnancy without help or through the use of fertility drugs and/or intrauterine insemination offers less than a 5% per month chance of having a baby. Given such relatively poor odds many such women, for good reason, turn to IVF as it can significantly improve the chance of becoming pregnant before time runs out. However IVF is certainly not a panacea.

Regardless of the method used to achieve a pregnancy, older women inevitable will have to confront the following hurdles:


  • A progressive and accelerated decline in egg quality

  • A progressive decline in the number of eggs they will be able to produce in response to fertility drugs (as evidenced by rising FSH , and declining AMH and Inhibin B levels

  • A marked increase in the miscarriage rate, which could be as high as 60% by age 45.

  • An increased risk of chromosomal birth defects such as Down’s Syndrome which reaches 1 in 30 by age 45.


Another factor to be considered is the fact that many women trying to start a family at an older age would often like to have more than one baby. In such cases, they will need to come to terms with the fact that by the time they have had their first child and have breastfed for a year or so, 2-3 critical years will have been lost, making the likelihood of having another baby (even through IVF) much less probable.

It is important to recognize that the main reason for declining fertility with age relates to a progressive and inevitable decline in the chromosomal integrity of a woman’s eggs as she advances beyond her mid 30’s and into her 40’s. The simple fact is that there is no medical remedy for this problem. As an example; at 30-35 years about 40% of a woman’s eggs are chromosomally normal. At 40, less than 20% are likely to be normal, while by age 45, well under 10% are chromosomally intact. The good news is that a chromosomally normal egg is just as likely to propagate a healthy embryo/baby regardless of the age of the egg provider. A chromosomally normal egg from a woman of 45 probably has the same chance of producing a healthy baby as does a normal egg taken from a 25 year old.

Recently, the introduction of comparative genomic hybridization (CGH) enables us to identify chromosomally “competent” eggs or embryos. Such normal embryos transferred to the uterus of a healthy woman would propagate a healthy baby i.e., about 60% of the time, regardless of the age of the “egg provider.”

What is embryo banking/stockpiling all about? We recently began offering women the opportunity to freeze/store and then stockpile/bank their CGH-normal embryos for future dispensation. To do this, they undergo multiple IVF procedures that each proceed through fertilization of their eggs. The resulting embryos are then biopsied and allowed to progress to the blastocyst stage (the most advanced preimplantation stage of embryo development), whereupon they are vitrified (ultra-rapidly frozen) and then banked.

Several such cycles are conducted in the hope of stockpiling a number of advanced embryos (blastocysts) for later use. Once the last cycle of embryo banking is completed, the biopsied samples derived from all surviving blastocysts are subjected to genetic (CGH) testing only once, thereby minimizing cost that otherwise would have had to be incurred were CGH testing were to be performed after each procedure.

Selective banking of genetically tested embryos in women for whom the end of their reproductive careers is in sight, dramatically expands reproductive choices available to them. First, it allows them to have more than one baby without the ever-present fear that by the time they have had the first one they might not be able to have another. Second, for women who are only interested in having one baby, it establishes realistic and rational expectations of success versus failure, and thus will help them decide when it is time to stop doing IVF, adopt, or go to egg donation. Simply stated, it establishes either a favorable resolution or closure.

It behooves all individuals/couples who are intent upon having a family to be aware of the fact that a woman’s biological clock cannot be reset. It is relentless, merciless and unforgiving. It is also well to bear in mind that a woman’s fertility potential can suddenly decline over a few years - both due to, or independent of, advancing age. While the threat of declining fertility is greatest in the late 30’s and early 40’s, it could just as easily occur in younger women. Because of this reality, women of reproductive age are well advised to undergo hormonal and physical assessments of their fertility potential every few years and to increase the frequency in their mid-30s.

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