Beta-hCG testing to find out whether pregnancy has occurred or not after a Frozen Embryo Transfer can be done within 15 days approximately, which allows you to get more accurate results. If done early, the test may give you a false negative or false positive result back.
There are cases, for example when blastocyst (day 5-6 of development) embryos are used, when the test can be done as early as 10 days after the FET. In any case, the general recommendation is to wait two weeks to take a pregnancy test.
Read the full article on: How Does the Frozen Embryo Transfer (FET) Procedure Work? ( 59).

Rebeca Reus
BSc, MSc
Degree in Human Biology (Biochemistry) from the Pompeu Fabra University (UPF). Official Master's Degree in Clinical Analysis Laboratory from the UPF and Master’s Degree about the Theoretical Basis and Laboratory Procedures in Assisted Reproduction from the University of Valencia (UV).