It has long been accepted that the primary reason that human eggs don’t age well is due to a dysfunction in when and how the chromosomes separate. This reduced chance of becoming pregnant associated with aging as well as the increased miscarriage rates. A new paper has now demonstrated that it’s not just the DNA separation that declines with time but also how the chromosomes are actually sorted and divided.
Within each egg are cable-like structures called microtubules. These microtubules not only help the egg maintain its shape but also are integral in sorting/separating the DNA. They are also in charge of cell division after fertilization is complete. In fact, some of the most powerful cancer fighting drugs are used to deliberately damage microtubules in order to prevent cancers from growing. This new information provides us with further insight into another important aspect of egg quality.
Although we don’t currently have any specific recommendations on what we can do to improve microtubule function; this information does provide us with more diagnostic information for patients that are going through In Vitro Fertilization (IVF). IVF is not only the treatment that provides patients with the highest pregnancy rates but when performed in a high quality setting; it also provides important diagnostic information. There is no accurate test for egg quality except to put a healthy sperm inside and see if/how well the process of fertilization and development takes place. We routinely use this information in discussing treatment options for patients that do not successfully conceive in their first IVF cycle at our center.
Robert Greene, MD, FACOG
Conceptions Reproductive Associates