If you suffer from certain genetic illnesses, or carry a gene for that illness, scientists can take one or two cells to check for those genes and transfer only healthy embryos.
It is possible to only transfer healthy embryos due to genetic testing.
( z1 possible :ARG1 ( z2 transfer :ARG1 ( z3 embryo :mod ( z4 healthy ) ) :mod ( z5 only ) ) :ARG1-of ( z6 cause :ARG0 ( z7 test :ARG2 ( z8 genetics ) ) ) )