Pregnancy begins at conception when the sperm meets the egg. After joining, fertilization occurs, and the fertilized egg travels to the uterus and implants about six days later.
If you have received a positive pregnancy test, fertilization and implantation have already happened, and your body is beginning to produce the hormone hCG.
If you have not yet confirmed your pregnancy or taken a pregnancy test, visit Elevier Women’s Center. We’re here to help you find answers so you can move forward.
The Fertilization Process
The germinal stage is the first and shortest stage of fetal development. It starts with a fertilized egg in the fallopian tube, known as a zygote, that travels down the fallopian tube toward the uterus over the course of a week.
What Is a Zygote?
A zygote is another name for the fertilized egg. It contains genetic information (DNA) necessary for a child. Half of the DNA comes from the sperm, and the other half from the egg, creating a one-of-a-kind combination.
At this point, genetics are determined. Will the resulting child have blue, green, or brown eyes? Will they be male or female? All these questions have microscopic answers.
At this point, the zygote is only one cell.
Time to Divide
After becoming a zygote, the cells start to divide. After about 30 hours, one cell divides into two and then into four cells about fifteen hours later. Three days later, there should be 16 cells, which form a structure called a “morula” (Latin for mulberry because it looks berry-like).
The morula continues to move down the fallopian tube toward the uterus, guided by hairlike structures in the fallopian tubes called cilia.
The zygote will divide into a morula and then into a blastocyst, which is the size of a pinhead and contains hundreds of cells.
The blastocyst looks like a ball of cells. The inner cells become the embryo, and the outer cells become membranes to nourish and protect the embryo.
Entering the Uterus to Implant
After several days of traveling, the blastocyst eventually enters the uterus. This moment is critical. If the blastocyst successfully implants in the wall of the uterus, the pregnancy will continue. If not, the pregnancy will not survive.
If implantation happens, your body will begin creating the hormone hCG, which will trigger your body to stop your menstrual cycle. However, it takes time for hCG to build up to detectable levels.
Starting around Week 3, the blastocyst will take on distinct human characteristics and be called an embryo.
By the time you miss your period, you will likely be around four weeks pregnant (counted from the first day of your last menstrual period.) Your hCG levels should be high enough to receive a positive pregnancy test.
Are You Ready to Take a Test?
Are you experiencing pregnancy symptoms or wondering whether or not you could be pregnant? Schedule a no-cost appointment at Elevier Women’s Center for a lab-quality pregnancy test.
If you receive a positive test result, we will provide evidence-based medical information and an ultrasound if you qualify. We can support you during this time.