Bigger not better


Research about babies born using in vitro maturation (IVM) seems to indicate that they will be larger at birth and likely require medical intervention for safe delivery. IVM is the process where eggs are harvested and then matured in the lab for several days before being fertilized and implanted. The researchers are urging caution with the use of IVM until a more direct and larger study can be done.

Dr. Peter Sjoblom from the Nottingham University IVF clinic at Queen’s Medical Centre explained at the annual meeting of ESHRE that they looked at data from four different countries (Denmark, Finland, Canada and Korea) and the numbers appeared consistent. “We strongly believe these findings must be explored further,” he said.

The scientists found that birth weight of the 165 IVM babies was between 0.3% and 6% higher than naturally conceived singleton births and 6%-9% higher than babies conceived with IVF and/or ICSI. Cesarean rates were consistently higher as well, 30%-60% as compared to the IVF/ICSI births which were 27%-44% higher than the spontaneously conceived births.

The reasons for these results are unclear, and he could only speculate as to why the babies would be larger. “It has been described in the literature that gene expression is altered in IVM eggs compared to those matured naturally in the body; it may be the case that the final stages of egg development before ovulation involves events that are crucial to development and that this is not happening when they are matured in the lab. Another explanation could be that the preparation of the lining of the womb is different and this may influence development, as has been shown in animal studies,” conjectured Dr. Sjoblom.

The long term consequences are also unknown. He urged that the babies be tracked into adulthood for signs of differences in physiological development. Until then, more research is needed and parents should be informed.

Source: Medical News Today


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