Where to Place Your Bet: The Difference Between Egg and Embryo Freezing

Who doesn’t love a good pre-game? Standing in a parking lot with the sun beating down on your back, relaxing with your friends: life couldn’t be better. While you may don a Giants jersey and your friend Eagles green, your pregame rituals are pretty much the same. Good food, good drinks, good times. When you enter the stadium, that’s when things start to change.

The same can be said for the difference between freezing eggs and freezing embryos. The “pre-game” part is pretty much the same—you take injectable gonadotropins (hormones) on a daily (sometimes twice daily) basis. This doesn’t change whether you are freezing eggs or embryos. Additionally, in both cases the medications and the morning visits will most likely start with the start of your period and go on for about 10 days. Therefore, in terms of the stimulation (a.k.a. the pre-game process) the two are pretty much the same. It is not until the eggs are retrieved that you run to opposite sides of the field.

If you’re rooting for team egg freeze, here’s what your game plan will look like once we start to play ball. Shortly after the eggs are retrieved, they will be evaluated for their stage of development (mature versus immature). Those that are mature will be frozen immediately. And this is where the information about your eggs and your fertility ends. You will know nothing more about your frozen friends other than quantity. We cannot tell how many will be “good” (a.k.a. make a baby) and how many will be bad (a.k.a. do nothing). But as most American possessions go, the more, the better. Women who have more eggs frozen will have a better chance of pregnancy from them in the future.

And in the blue corner, we have team embryo freezing! For those that choose to embryo freeze, after the eggs are extracted they will be fertilized with sperm. The resultant embryos will then be watched over the next several days in the laboratory. How they grow, how they divide, and how they develop is very telling for their health. Some, if not several, will drop off along the way—those that can’t hack it in the lab would definitely not hack it in the uterus.

In many ways, the lab is like the ultimate test of survival, or natural selection. At the end of the game, you may only have a few players on the field, but these players are tough, resilient, and really know how to play the game. They have weathered the storm and are your true MVPs.

In many ways, egg freezing is like drafting a player who has demonstrated potential in college but has not yet played in the big leagues. They should be good, but you can’t know for sure. It’s also hard to survey the newbies in spring training and know who and how many superstars you’ll have at the end of the season.

In the same vein, if your ovarian reserve tests are normal and there are no red flags in your medical history, you should have some good potential in your eggs. Embryo freezing is like signing a player who has already won rookie of the year. You know more about the player’s (a.k.a. embryos’) ability to hit it out of the park because they have already been vetted. Take it one step further…if your embryos undergo PGS (also called CCS or TE biopsy—the chromosomal analysis of embryos), we have even more information about their ability to make a baby. You have vetted them in the most aggressive way possible.

For many women, embryo freezing is not even an option. Unless you have a partner or chose to use donor sperm, without a sperm source, you can’t make embryos. The lack of sperm and the ability to make embryos are NOT a bad thing AT ALL! And we definitely don’t recommend using donor sperm just to make embryos and have more information about your egg quality. In these situations, egg freezing is totally the way to go! Additionally, even if you have a partner, egg freezing may be a better option for you. Not to be Debbie Downers, but nearly half of all relationships end in divorce. So be careful about who you mix your gametes with!

If you are even thinking about freezing, be it eggs or embryos, you’re being proactive. You are several steps ahead of the game. It’s like you’re planning your roster months before opening day! Either way you do it, you’re giving yourself options and choice. And that’s really why you did this in the first place. So however you get on the field, you are here to play ball—go, girl, go!