After a long wait or a surprise, you get a positive result! Then you start imagining what’s happening inside your body and your system. What is the beginning of pregnancy like, what should you expect, and what is really happening in the first weeks of pregnancy? How is the baby and how is your body reacting to early pregnancy?
How It All Starts
Contrary to what many women think, pregnancy actually starts on the first day of menstruation—did you know that? For correct calculation, doctors begin counting from the first day of a woman’s real period to determine the 40 weeks or about 280 days. However, this calculation may change depending on the first ultrasound scan. In this case, what really counts is the date shown there, not the date of your last period. This is because ovulation can happen on a different day—before or after what is estimated by your LMP (last menstrual period).
The fertile window is the starting point for pregnancy. When a woman is able to conceive, her body starts giving signs—there are subtle changes, such as a change in cervical mucus (vaginal discharge) and even behavioral signals like increased libido and the desire to have sex.
An egg is released into the fallopian tube and is capable of receiving only one sperm. After one enters, the outer layer becomes impenetrable and blocks any others from getting inside. With actual conception, the pregnancy project begins—that’s because we can only say a woman is truly pregnant when the embryo implants in the endometrium (nesting).
The Big Encounter
After the egg meets the sperm—just two cells—the baby’s cell multiplication begins. On the first day, two cells join, then they divide into 2, and those into another 2, and so on, multiplying repeatedly.
On the third day after fertilization, the baby, which at this stage is a morula, has about 7 to 10 cells. By days 5 to 12, it becomes a blastocyst with about 400 cells. This is when implantation occurs. The baby finally arrives in the uterus after a journey lasting days, slowly guided by the tiny “little hands” inside the uterus, traveling safely and gently.
Implantation
Once it reaches the bottom of the uterus, the embryo attaches itself, creating a kind of root that will remain for the entire pregnancy. This event is expected between 7 and 15 days after conception. From this point, the woman is truly pregnant and it’s possible to confirm pregnancy with a urine test or a beta HCG blood test.
Implantation is extremely important—it determines the health of the pregnancy and the viability of the embryo. If the embryo attaches poorly, problems such as sacs separating can occur, for example. There is a specific region where the embryo lodges, and the endometrium (the blood layer that would have become the period) becomes suitably thick, usually above 8mm, which holds the baby with help from hormones such as progesterone—which maintains the pregnancy in these early days.
One detail many women do not know is that after implantation, there may be some small bleeding caused by nesting. It’s not a large amount and usually lasts for 1 to 3 days—around when your period would have come. The blood is pinkish, reddish, but lighter than a regular period.
After Implantation
After implantation, the blastocyst (the baby project) divides into two parts. One will become the placenta, gestational sac, yolk sac, and all the support needed for the baby. The other part will become the embryo itself. It all begins with the neural tube, which is why supplementation with L-methylfolate or folic acid is so important—they help prevent neural tube defects, which is the basis for forming the new individual.
It’s recommended to start taking methylfolate 3 months before trying to conceive, and continue taking it through the first 12 weeks of pregnancy. The first 12 weeks are crucial for proper development. During this phase, the uterus begins to expand to accommodate recent and future changes.
First Signs of Pregnancy
At the start of pregnancy, with the baby’s implantation, the corpus luteum (the scar from where the egg left the ovary during the fertile window) becomes very active. It encourages the production of progesterone, and as a result, HCG—the pregnancy hormone—rises every day. You can already have more than 1000 mIU of pregnancy hormone at this stage—sometimes more, sometimes less, but what matters is that it’s always increasing.
The right thing to do is to get a quantitative beta HCG test and repeat it after 3 days. This way, with an HCG calculator, you’ll know if your body is producing the pregnancy hormone properly. As progesterone increases, the first symptoms of pregnancy appear, such as:
- Nausea
- Drowsiness
- Salivation
- Mild abdominal pain (similar to cramps)
- Salivation
- Aversion to smells
- Lower abdominal bloating
You might be feeling something different, so take a test! Did you get a positive result? Celebrate a lot! Being pregnant is a blessing that thousands of women hope for every cycle—feel privileged to receive the miracle of life!
Enjoy your little one each day, every symptom and every new thing that comes. Don’t forget to schedule your prenatal appointments and take all necessary tests, okay? Ultrasound is best performed after 6 weeks of pregnancy to avoid early surprises, since you may only see the gestational sac and yolk sac at first. The baby will appear around 6 weeks, and the heartbeat at 7. Make the most of this moment!
