IVF screening reduces pregnancies in older women

Many women today decide to put off having a family, for one reason or another, until their late 30s and early 40s. Unfortunately, this is not the best time to be trying to conceive because fertility is much reduced by this time. Several issues involved include infertile cervical mucus and lower quality of eggs in the ovaries amongst others. Many couples have to resort to in vitro fertiliation (IVF, otherwise known as having a test tube baby). Women also have a higher chance of having babies with birth defects as they get older because the quality of the eggs decreases with age.
To help reduce the risk of having babies with birth defects, embryos obtained from IVF are screened for various diseases to avoid putting defective embryos into the uterus.
A recent study found that older women (between 35 and 41 years) whose embryos were screened were less likely to have a successful pregnancy. Screening of embryos involves removing one or two cells from the embryo to test for disorders like Huntington’s disease, sickle cell anemia and cystic fibrosis. It is especially recommended for couples who have a family history of any of these disorders or in women who have had recurrent unexplained abortions that suggests the presence of abnormal embryos.
24% of the women who had their embryos screened had a successful live delivery compared to 35% in the group that did not have screening.
Several things may account for this difference:

• The act of removing cells from the embryo may damage it.
• Not all conditions can be detected by screening.
• The sample for testing may be taken from an area that has normal cells leaving the abnormal ones behind.

Couples who are at high risk of having abnormal babies may be willing to pay the price of screening IVF embryos in terms of the decreased likelihood of having a baby and in terms of hard cash. Prices for testing embryos range from $3000 to $5000.
As usual there are some disagreements with this study. Some observers point out that the pregnancy rates achieved for women who did not have embryo testing were lower than what is achieved in other centers in the US and so this casts some doubt on the expertise of the technicians involved in these procedures.
It is important for couples to be presented with the pros and cons of any procedure that they are going to be subjected to so they can choose just how much risk they are comfortable with.