Doctors at the Shandong Provincial Hospital in China recently published the results of their study, which tracked the IVF success rates of 1,508 women undergoing treatment for the first time. The women were all randomly assigned either to a fresh embryo transfer that took place immediately after fertilization, or to wait one month after harvest to implant the frozen embryo.
In the end, 42% of those who used fresh embryos eventually gave birth to a baby, while 49.3% of the frozen embryo recipients did. An important caveat on these success rates: this was only on the first try; of the 44% of infertile women who seek out medical intervention, 65% of them will eventually give birth.
However, there are more nuances to the study. There were no differences in the rates of initial pregnancy between the two groups, researchers say. But 33% of women with the fresh embryo lost the baby over the course of the pregnancy, compared to only 22% of women with frozen ones. The frozen embryo babies also had higher weights upon birth.
These may seem like minor differences, but those numbers represent real women who had their dreams of motherhood come true -- or not.
Another important note about this study is that all of the women involved had PCOS, or polycystic ovary syndrome, which makes women infertile. In reality, there are many causes of infertility, not all of which can be attributed to the female partner. One in eight couples and 12% of women have trouble getting or staying pregnant; one-third of cases can be attributed to the woman, one-third to the male partner, and one-third to any unexplained combination of factors.
Whether these results apply to all women or just women with PCOS is unclear. It does, however, raise a significant point about how we measure IVF success rates. Currently, official numbers are measured by the number of pregnancies, not the number of live births. In this case, pregnancy rates were similar, but the birth rates were not. Since a healthy baby is the end goal of all IVF treatments, this study could change the way doctors think about IVF success rates in the future.
Are you a Michigan woman or couple struggling to conceive? Then it's time to consult with the Michigan Infertility Expert, Dr. Mostafa I. Abuzeid.