Does a pregnancy loss after an embryo transfer make another loss more likely?

What did this research set out to answer?

Researchers wanted to understand whether experiencing an early pregnancy loss after a frozen embryo transfer (FET) affects what happens with the next embryo transfer.

They looked at two types of early pregnancy loss:

Biochemical pregnancy loss: a pregnancy detected by a blood test that does not progress to a pregnancy seen on ultrasound

Clinical pregnancy loss: a pregnancy seen on ultrasound that does not progress to a live birth

The researchers asked whether patients who experienced either type of loss after their first embryo transfer were more likely to experience another pregnancy loss after their next transfer.

What did the researchers do?

Researchers reviewed past treatment data from 2,385 patients who underwent two consecutive single frozen embryo transfers between 2017 and 2021.

Of these, 2,103 patients had two consecutive transfers of chromosomally normal, or euploid, embryos, and 282 patients had two consecutive transfers of embryos that had not undergone genetic testing.

Patients were grouped based on what happened after their first transfer: biochemical pregnancy loss, clinical pregnancy loss, or implantation failure (negative pregnancy test). Researchers then compared what happened after each patient's second transfer.

The researchers also considered factors that could affect pregnancy outcomes, including age, embryo characteristics, body mass index, endometrial thickness, hormone levels, and the type of frozen embryo transfer protocol used.

What did the research find?

Experiencing a biochemical or clinical pregnancy loss after the first embryo transfer was not associated with a higher risk of pregnancy loss after the second transfer.

This was true for patients transferring euploid embryos and for patients transferring embryos that had not undergone genetic testing.

Among patients transferring euploid embryos, rates of biochemical and clinical pregnancy loss after the second transfer were similar whether the first transfer resulted in a pregnancy loss or negative pregnancy test.

Live birth rates after the second euploid transfer were also similar regardless of the outcome of the first transfer: 58.7% after a prior biochemical loss, 53.7% after a prior clinical loss, and 56.1% after prior negative pregnancy test.

What does this mean for patients?

An early pregnancy loss after one frozen embryo transfer can understandably raise concerns about whether the same thing is likely to happen again.

In this study, one biochemical or clinical pregnancy loss did not appear to increase the risk of another pregnancy loss with the next embryo transfer.

The results may provide some reassurance that the outcome of one embryo transfer does not necessarily predict the outcome of the next.

However, this was a retrospective study, and it looked specifically at patients undergoing consecutive frozen embryo transfers. It also evaluated pregnancy loss following an embryo transfer and did not account for patients who may have experienced pregnancy loss prior to IVF treatment. Your care team can consider your individual treatment and pregnancy history when discussing what these findings may mean for you.

Barrett, F., Kalafat, E., Vessa, B., Margolis, C., Whitehead, C., Werner, M., Ata, B., & Seli, E. (2026). Biochemical or clinical pregnancy loss after first embryo transfer does not affect subsequent transfer outcome. Reproductive BioMedicine Online, 52(4), 105435. https://doi.org/10.1016/j.rbmo.2025.105435