From the Fertility Institutes of LA web site:
How does it work?
Several eggs are extracted from the mother by our doctors, sperm is supplied by the father. The father's sperm is used to fertilize the mother's eggs in our lab. After 3 days, several 8-cell embryos will have developed. Our doctor-scientist specialists examine the genetic makeup of the embryos, screening for both genetic diseases and desired gender. Healthy embryos of the gender you desire are implanted in the mother. Any additional healthy embryos may be cryo-frozen for future use. Gestation and birth take place as normal.
So, I'm thinking the scene from Gattaca. That seems to be a specialty of their clinic.
Something to remember...implantation is the actual moment an embryo burrows into the mother’s uterus and starts relying on her life for it’s own.
The word “implanted” seems to be used wrong a lot...referring to when embryos after IVF are RETURNED to the uterus where they float around a bit before IMPLANTING in the uterus lining...two different things. Just returning embryos to the uterus does not guarantee that pregnancy will occur.