Category
Dec 4, 2025
You have just walked out of the clinic. The transfer went well, the embryo is "home." But as soon as you step through your front door, the initial euphoria often gives way to uncertainty. The "Two-Week Wait" (Beta-wait) begins.
We know these 10 to 14 days can paradoxically be harder than the injections or the retrieval. Every twinge, every absence of symptoms, every trip to the bathroom becomes an agonizing question: Is it working?
In this article, we want to be your voice of reason. We will explain what is happening invisibly inside your uterus so you can understand your body's signals without fear.
For the seed to grow, the soil must be ready. In assisted reproduction, we leave nothing to chance.
What is a Receptive Endometrium? The endometrium is the inner layer of the uterus. To receive the embryo, it must have a specific thickness (ideally >7mm) and a "trilaminar" appearance on the ultrasound. It is the "mattress" where the embryo will rest.
The Window of Implantation: The uterus does not have its door open forever. There is a brief and magical period, called the "window of implantation," where the endometrium expresses the necessary molecules to "catch" the embryo. We coordinate the transfer with millimetric precision to hit this exact moment.
It is the biological process that defines success, but it is silent and invisible.
Definition: Implantation It is the critical process where the embryo (at the blastocyst stage) breaks its outer layer, adheres to the uterine wall, and penetrates it to connect with the mother's blood system.
When does it actually happen? It is not immediate. If we transferred a blastocyst (Day 5), actual implantation usually begins between 24 and 48 hours after the transfer. That is why absolute bed rest immediately after is not necessary; the embryo does not "fall out," it needs time to initiate the chemical dialogue with your uterus.
What is the Two-Week Wait? We call it the "Beta-wait" (or Two-Week Wait), the period between the embryo transfer and the pregnancy blood test (Beta-hCG). It is the time it takes for the embryo to produce enough hormone to be detected.
The Deception of Symptoms: Here is where we need you to trust science and not (just) your intuition.
Do you feel bloating or drowsiness? It is likely the progesterone you are taking, not necessarily the pregnancy.
Do you feel absolutely nothing? It is completely normal. Many healthy pregnancies show no symptoms in the first few weeks.
Conclusion: Symptoms are not a reliable oracle.
Seeing a spot of blood is a patient's greatest terror during the wait. But often, it is a false alarm.
Definition: Implantation Bleeding It is slight spotting (pink or brown, not bright red) that occurs when the embryo, while "digesting" its nest in the endometrium, breaks small blood capillaries.
This does not happen to every woman, but if it happens to you, do not stop your medication. Breathe deeply. It is often the physical sign that the nesting process is taking place.
We know the temptation to take a home urine test is enormous. We ask for patience for a medical reason.
What is Beta-hCG? Human Chorionic Gonadotropin (hCG) is the hormone the embryo manufactures. The blood test ("the Beta") is the only precise way to measure it.
Why wait for the scheduled day?
False Negatives: If you do it too early, the hormone may be undetectable even if you are pregnant.
False Positives: Medications like Ovitrelle can leave traces in urine and give you false hope.
Sometimes, despite a perfect embryo—cultivated with our Music in Incubators technology—and a ready endometrium, pregnancy does not occur.
Definition: Implantation Failure We speak of implantation failure when pregnancy is not achieved after several transfers of good quality embryos. In most cases, the cause is genetic or immunological. At Institut Marquès, we do not repeat the same thing expecting a different result; we investigate the cause (with PGT or endometrial studies) to change the strategy.
Do I need bed rest after the transfer? No, absolute bed rest does not increase pregnancy chances. We recommend a quiet but normal life. Avoid intense physical effort and immersion baths (tubs, pools) for the first few days.
When is the earliest I can take a pregnancy test? We advise waiting 10 to 14 days. Testing earlier can lead to false results due to medication or low hormone levels.
Why do I take progesterone if I don't know if I'm pregnant yet? Progesterone is essential to maintain the uterine lining. Without this support, the embryo could not implant or stay attached. Never stop medication until the doctor confirms the Beta result.
