One of the most common questions is "How many embryos should be transferred back to the uterus at the time of in vitro fertilization?" Once the eggs are retrieved from the ovaries, the eggs are fertilized, and a few days later there are hopefully a significant number of embryos that are potentially capable of being transferred back into the uterus. This is important for every couple to discuss with their physician. What are the chances of pregnancy, and what are the chances of multiple pregnancy, and to balance those chances.
In general, the more embryos transferred back into the uterus, the greater the chance that pregnancy will occur. However, there's also a very high rate of multiple pregnancy with the transfer of multiple embryos. In general, the younger the woman is, the less the number of embryos that should be transferred. In recent years, there's been a significant attempt to try to do more elective transfers of single embryos as opposed to multiple embryos. The chances of pregnancy using single embryos is good if the woman is young, typically under 35, has high-quality embryos, or has embryos available for freezing or cryopreservation.
With better culture media today, better in vitro techniques, and the capability of freezing embryos effectively, the option of doing single embryo transfers or double embryo transfers are, in fact, viable options. Be sure to speak with your physician about the number of embryos to transfer. In that discussion, you should also determine what your feelings are about multiple pregnancy, and also what your feelings are about reducing the pregnancy. In cases of which more than two embryos implant in the uterus, many fertility physicians and high-risk pregnancy physicians recommend the reduction of the pregnancy to either a single or twin pregnancy. That reduction is not always emotionally easy for a couple to do. So, the couple should never placed in that position unnecessarily. Therefore, discussion prior to embryo transfer is imperative.