Send to

Choose Destination
Reprod Biomed Online. 2018 Sep;37(3):349-357. doi: 10.1016/j.rbmo.2018.05.019. Epub 2018 Jun 30.

Biochemical pregnancy loss after frozen embryo transfer seems independent of embryo developmental stage and chromosomal status.

Author information

GENERA Centre for Reproductive MedicineRomeItaly; Unit of Gynecology and Obstetrics, Department of Human Pathology in Adulthood and Childhood 'G. Barresi'University of MessinaMessinaItaly. Electronic address:
GENERA Centre for Reproductive MedicineRomeItaly; Sezione di Istologia ed Embriologia MedicaUniversity of Rome 'Sapienza'RomeItaly.
Yale University Fertility CentreNew HavenCTUSA.
Department of Obstetrics and GynaecologyMagna Graecia University of CatanzaroCatanzaroItaly.
GENERA Centre for Reproductive MedicineRomeItaly.
Sezione di Istologia ed Embriologia MedicaUniversity of Rome 'Sapienza'RomeItaly; IgenomixMarostica(VI)Italy.



Biochemical pregnancy loss (BPL), defined as serum beta-human chorionic gonadotropin levels ≥50 IU/l in at least two pregnancy tests, not associated with any ultrasonographical evidence of pregnancy, is often attributed to chromosomal abnormalities; however, no hard evidence exists to support this hypothesis. Are any IVF cycle parameters associated with the occurrence of a BPL?


Retrospective study aimed at evaluating the effect of embryo developmental stage at transfer and chromosomal assessment on the BPL rate in IVF after frozen embryo transfer (FET). Specifically, 641 FET of 1179 cleavage stage untested embryos (Group A), 1021 FET of 1259 untested blastocyst stage embryos (Group B), and 789 blastocyst stage FET of 803 euploid embryos (Group C) were performed in a 6-year period. Only FET were evaluated to avoid a potential effect of ovarian stimulation on endometrial receptivity.


The BPL rates were similar (n = 30/217, 13.8% in Group A; n = 37/412, 9.0% in Group B; n = 42/433, 9.7% in Group C). Neither embryo developmental stage at FET nor chromosomal assessment showed a correlation with BPL. Furthermore, logistic regression analyses did not show any association between BPL and patient, cycle and/or transfer characteristics.


BPL seems independent of the embryo's developmental stage, the use of trophectoderm biopsy and the chromosomal constitution at FET. Similar BPL rates after transferring euploid blastocysts compared with both untested cleavage and blastocyst stage embryos suggest investigating the role of endometrial and other embryonic factors putatively involved in the process of implantation.


Biochemical pregnancy loss; Blastocyst; Cleavage stage embryo; Euploidy; Frozen embryo transfer; PGT; preimplantation genetic testing

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center