Small blood clot after embryo transfer

  1. avatar
    Michelle Salgado

    Hello Doctor, how are you? Thank you for helping us. I had a frozen blastocyst transferred last 31st of March and now I’m taking progesterone. Two days after the transfer I lost like a small blood clot (like a small golf ball). It was a brown blot clot of around 2 mm long. I know it may be difficult for you to identify what was that, but I wanted to know if maybe it was the blastocyst due to its rounded shape. From today (5 days post embryo transfer) I feel nausea and feelings of vomiting every time… Do you know if it is caused by the treatment or is it a signal that I’m pregnant?

    April 5, 2016 at 5:08 pm
  2. avatar
    Sandra F.
    Fertility counselor

    Hello Michelle,

    blastocyst embryos cannot be seen with the naked eye, that is, you need to see them through microscope. It is likely that it was just a blood clot, which is a common symptom after an embryo transfer and, since it was 2 days after the transfer, it may be due to the pass of the cannula through your vagina. This is the reason why it is brown and not red, as it was what we call “old” blood.

    Do not worry as it is a totally normal symptom and does not indicate either it worked or not. Nausea and vomiting are also included within the most common post embryo transfer symptoms, so don’t panic. If it’s only 5 days post embryo transfer, it is still too early to find out whether you’re pregnant or no. I’m afraid you have to wait till at least day 10 or 11 to take a pregnancy test and get an accurate result.

    I hope I have been able to help,


    April 6, 2016 at 8:55 am
  3. avatar
    Sabrina Algu

    This is my second ivf cycle and this cycle I transferred 2 frozen embryos. Today is 7 days after transfer and notice a flow like I was getting my period as well as a small blood clot but stop bleeding later today. Is this something to worry about?

    May 4, 2017 at 2:10 am
    • avatar
      Sandra F.
      Fertility counselor

      Dear Sabrina,

      Taking into account that it’s day 7 post embryo transfer, there’s the possibility that that flow and small blood clot you’ve observed are related to embryo implantation—what we know as “implantation bleeding” to be precise. It’s a common symptom when the embryo attaches to the uterine lining of the woman, although it does not happen in every woman.

      On the other hand, it could be also related to the medications you’ve been taking for endometrial preparation, in which case it does not translate directly into the embryo being attached. Either way, and depending on the day of development when the embryo was transferred back to your uterus, you won’t be able to make sure which one of the causes I’ve mentioned above is really behind these symptoms until you take a pregnancy test .

      Good luck! Looking forward to hearing from you again,


      May 4, 2017 at 8:22 am