IVF babies born from frozen embryos are healthier and result in longer pregnancies, compared to those from fresh embryo, suggest a recent study. The latest research suggests that frozen embryo transfer in IVF process may escort to healthier babies. Due to good birth weight, the foetus has ability to last the course of pregnancy without being premature.
Researchers from the Centre for Reproductive and Genetic Health, London carried out a study involved calculating the weight and duration of gestation of three hundred and eighty four babies born after fresh embryo transfer and one hundred eight babies born after frozen embryo transfer. All the babies were born from singleton pregnancy with no twin or triplet pregnancies included in the study.
The finding of the study showed that babies born from frozen embryo were heavier by two hundred and fifty gram than babies born from fresh embryo. The proportion of low birth weight was also lower in babies born from frozen embryo. In addition to that babies born from frozen embryo characteristically had a longer gestation than those born from fresh embryos.
According to lead author Suzanne Cawood, for all assisted reproduction technologies, it is important to ensure the procedures promote optimal health in the resulting babies throughout their lives. The study suggests that babies born from frozen embryos have a significantly longer gestation period and are significantly heavier at birth compared to babies from fresh embryos.
This is significant as preterm and low birth weight are both risk factors for poorer health later in life and are associated with higher rates of behavioral and learning difficulties. This means that resulting babies may potentially be healthier if frozen embryos are transferred rather than fresh embryos.
One possibility behind these findings may be that there is a difference in the uterine environment between fresh cycles, when embryos are transferred soon after the eggs have been collected, compared to frozen cycles when the uterus has not been stimulated in the days before transfer. Further study is required to verify this hypothesis, added Dr Cawood.
Previously, Danish researchers also found that babies born after frozen embryo transfer had higher birth weights compared to those born from fresh embryos. They also suggested that only embryo of top quality survive in the freezing and thawing process.