Embryo Pregnancy Stages

The embryo stage of pregnancy begins right after fertilization and lasts until approximately the eighth week of pregnancy, marking an essential phase in the development of the baby.

By knowing what to expect as the embryo grows into a healthy baby, you can better connect with the experience and stay informed about your health and the baby’s development.

Below is an overview of what occurs during this stage, common symptoms, and what you can expect as a surrogate moving forward.

Learn more about pregnancy as a surrogate here, or fill out this simple form to get help if you are considering becoming a surrogate.

What is the Embryo Stage of Pregnancy?

The embryo stage follows fertilization and extends until the eighth week of pregnancy. This early stage of development is crucial, as it’s when most of the baby’s fundamental structures begin to form, including vital organs, the nervous system and basic physical features.

Key Milestones in embryo development:

• Weeks 1-3: The fertilized egg (zygote) travels to the uterus and begins cell division. By the end of this period, the embryo implants itself in the uterine wall, marking the start of a physical connection that will nourish it throughout pregnancy.
• Weeks 4-5: Basic structures start to form. The neural tube, which will become the brain and spinal cord, begins to develop. Tiny limb buds also appear.
• Weeks 6-8: By week six, the embryo’s heart begins to beat, a major milestone. Facial features, including eyes, ears, and the mouth start to emerge, while the arms and legs continue developing. Around week eight, the embryo measures about half an inch, roughly the size of a raspberry.

What is embryo vs. fetal stage?

The embryo stage involves foundational development and ends at week eight; the fetal stage, which follows, involves maturation and growth.

Common Symptoms During the Embryo Stage of Pregnancy

As the embryo develops, surrogates may experience symptoms associated with early pregnancy. These can vary widely but are normal signs of pregnancy hormones at work. Here are some of the common symptoms of pregnancy:

• Morning Sickness: Nausea and vomiting, often in the morning but sometimes throughout the day, are common due to increased levels of hormones like hCG and estrogen.
• Fatigue: The body works hard during early pregnancy to support the embryo’s growth, often resulting in feelings of tiredness and the need for extra rest.
• Emotional Changes: Hormonal shifts can lead to mood swings, heightened sensitivity, and emotional fluctuations. This is completely normal and usually stabilizes in the later stages.

While these symptoms may be uncomfortable, they are temporary and tend to lessen or disappear as the body adjusts to pregnancy. If you are experiencing these symptoms, rest as needed and seek support if symptoms are challenging.

From the Embryo Stage of Pregnancy to the Fetal Stage

At around eight weeks of pregnancy, the embryo transitions into the fetal stage, signifying a new phase of development. By this point, the basic body structure and organ systems have started forming and the developing baby is now referred to as a fetus.

During this next stage, the fetus will continue to grow and mature, with organs becoming functional and physical characteristics becoming more defined.

What to Expect Going Forward in Your Surrogacy Journey

As surrogates move beyond the embryo stage of pregnancy, they enter a period of rapid growth and development in the fetus. The second trimester (weeks 13–26) is often associated with increased energy and fewer symptoms like morning sickness, and it’s a time when you may feel more comfortable and stable.

Here’s a quick look at what’s to come:

• Second Trimester: This phase is often called the “golden trimester” due to the decrease in early pregnancy symptoms. Surrogates may experience a boost in energy and well-being, and this is often when the baby bump starts to become more visible.
• Third Trimester: This final stage of pregnancy is marked by rapid growth of the fetus. Surrogates may feel more tired as they approach delivery, and physical changes become more pronounced as the body prepares for birth.

Your Unique Role Through Each Stage

The embryo stage of pregnancy is just the beginning of a beautiful, transformative process.

By understanding each stage as a surrogate, you can navigate each part of the journey with confidence. Remember that healthcare providers are there for support every step of the way.

Learn more about pregnancy as a surrogate here, or fill out this simple form to get help if you are considering becoming a surrogate.