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Calculating your FET due date

Calculating your FET due date

  1. <span  class="bbp-author-name">anastasia003</span>

    Hi everyone,

    I’ve been told the best option in my case is embryo freezing, since I can’t have my ET done within this IVF cycle because I’m at high risk of developing OHSS. However, I’m not quite sure about the whole process…

    I mean, if I have the embryos transferred next month, how can I calculate how many days have passed after egg retrieval until the embryos are returned to my body? Which is the ideal FET due date?

    Thank you very much.

    09/28/2015 at 12:44 pm
  2. Dear anastasia003,

    Embryo development “stops” from the very moment they are frozen. This means that if they were day-3 embryos, they’ll continue being day-3 embryos after being thawed. In case they’re frozen on blastocyst stage, they will be this age after being thawed as well, regardless if it is after 1 month or even 4 years. To sum up, embryos can be frozen at any stage during their development, either if they are day-1, day-5, or day-6 embryos. However, it is usually performed when they are on day 3 or on day 5, which are the most common days when FET is done.

    The following article shall be of interest: Day 5 vs. Day 3 Embryo Transfer – What Are the Pros & Cons?

    Hope this helps.

    09/29/2015 at 9:29 am
    • Hello all,

      My name is Sylvia and I’m from UK. Nice to meet you all… I’m more or less in the same situation as anastasia003. You see, I’m waiting to have my blastocyst transfer done. Till then, my doctor said I should start using contraceptive patches. Now I have an appointment to take an ultrasound and a blood test, and that day I will be on day 10 of menstrual cycle, so I’d appreciate if someone could kindly tell me what will be my FET due date and if there is some ideal date to do so.

      Thanks for your kind reply.

      09/29/2015 at 10:50 am
    • Hi Sylvia,

      ET is performed halfway the menstrual cycle onwards. For example, if you ovulate on day 14 naturally, embryo grading will be synchronized with your menstrual cycle before doing the ET. Take day-5 embryos, for example; the ET will be done on day 5 after ovulating.

      When you undergo the follow-up ultrasound, you will have your endometrial thickness checked so that it can be adapted to the above mentioned as well. As you may know, endometrial thickness should be adequate enough for the ET due date. This is the reason why you’ve been told to use contraceptive patches, because the endometrium should be as receptive as possible.

      Wishing you all the best.

      09/30/2015 at 12:56 pm