While you might think of child development as something that begins during infancy, the prenatal period is also considered an important part of the developmental process. Prenatal development is a time of remarkable change that helps set the stage for future psychological development. The brain develops over the course of the prenatal period, but it will continue to go through more changes during the early years of childhood
The process of prenatal development occurs in three main stages. The first two weeks after conception are known as the germinal stage,the third through the eighth week is known as the embryonic period, and the time from the ninth week until birth is known as the fetal period.
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This video has been medically reviewed by Carly Snyder, MD.
Thegerminal stagebegins at conception when the sperm and egg cell unite in one of the two fallopian tubes. The fertilized egg is called azygote. Just a few hours after conception, the single-celled zygote begins making a journey down the fallopian tube to the uterus.
Cell division begins approximately 24 to 36 hours after conception. Through the process of mitosis, the zygote first divides into two cells, then into four, eight, sixteen, and so on. A significant number of zygotes never progress past this early part of cell division, with as many as half of all zygotes surviving less than two weeks.
Once the eight-cell point has been reached, the cells begin to differentiate and take on certain characteristics that will determine the type of cells they will eventually become. As the cells multiply, they will also separate into two distinctive masses: the outer cells will eventually become the placenta, while the inner cells form the embryo.
Cell division continues at a rapid rate during the approximately week-long journey from fallopian tube to uterus wall. The cells develop into what is known as ablastocyst. The blastocyst is made up of three layers, each of which develops into different structures in the body.
- Ectoderm: Skin and nervous system
- Endoderm: Digestive and respiratory systems
- Mesoderm: Muscle and skeletal systems
Finally, the blastocyst arrives at the uterus and attaches to the uterine wall, a process known asimplantation. Implantation occurs when the cells nestle into the uterine lining and rupture tiny blood vessels. The connective web of blood vessels and membranes that form between them will provide nourishment for the developing being for the next nine months. Implantation is not always an automatic and sure-fire process.
Researchers estimate that approximately 60% of all natural conceptions never become properly implanted in the uterus, which results in the new life ending before the mother is ever aware she is pregnant.
When implantation is successful, hormonal changes halt the normal menstrual cycle and cause a whole host of physical changes. For some people, activities they previously enjoyed such as smoking and drinking alcohol or coffee may become less palatable, possibly part of nature’s way of protecting the growing life inside them.
At this point, the mass of cells is now known as anembryo. The beginning of the third week after conception marks the start of the embryonic period, a time when the mass of cells becomes distinct as a human. The embryonic stage plays an important role in the development of the brain.
Approximately four weeks after conception, the neural tube forms. This tube will later develop into the central nervous system including the spinal cord and brain. The neural tube begins to form along with an area known as the neural plate. The earliest signs of development of the neural tube are the emergence of two ridges that form along each side of the neural plate.
Over the next few days, more ridges form and fold inward until a hollow tube is formed. Once this tube is fully formed, cells begin to form near the center. The tube begins to close and brain vesicles form. These vesicles will eventually develop into parts of the brain, including the structures of the forebrain, midbrain, and hindbrain.
Around the fourth week, the head begins to form, quickly followed by the eyes, nose, ears, and mouth. The blood vessel that will become the heart start to pulse. During the fifth week, buds that will form the arms and legs appear.
By the eighthweekof development, the embryo has all of the basic organs and parts except those of the sex organs. At this point, the embryo weighs just one gram and is about one inch in length.
By the end of the embryonic period, the basic structures of the brain and central nervous system have been established. At this point, the basic structure of the peripheral nervous system is also defined.
The production of neurons, or brain cells, begins around day 42 after conception and is mostly complete sometime around the middle of pregnancy.
As neurons form, they migrate to different areas of the brain. Once they have reached the correct location, they begin to form connections with other neural cells, establishing rudimentary neural networks.
Once cell differentiation is mostly complete, the embryo enters the next stage and becomes known as afetus.The fetal period of prenatal develop marks more important changes in the brain. This period of development begins during the ninth week and lasts until birth. This stage is marked by amazing change and growth.
The early body systems and structures established in the embryonic stage continue to develop. The neural tube develops into the brain and spinal cord and neurons continue to form. Once these neurons have formed, they begin to migrate to their correct locations. Synapses, or the connections between neurons, also begin to develop.
Between the ninth and twelfth week of gestation (at the earliest), reflexes begin to emerge. The fetus begins to make reflexive motions with its arms and legs.
During the third month of gestation, the sex organs begin to differentiate. By the end of the month, all parts of the body will be formed. At this point, the fetus weighs around three ounces. The fetus continues to grow in both weight and length, although the majority of the physical growth occurs in the later stages of pregnancy.
The end of the third month also marks the end of the first trimester of pregnancy. During the second trimester, or months four through six, the heartbeat grows stronger and other body systems become further developed. Fingernails, hair, eyelashes, and toenails form. Perhaps most noticeably, the fetus increases about six times in size.
So what's going on inside the brain during this important period of prenatal development? The brain andcentral nervous systemalso become more responsive during the second trimester. Around 28 weeks, the brain starts to mature faster, with an activity that greatly resembles that of a sleeping newborn.
During the period from seven months until birth, the fetus continues to develop, put on weight, and prepare for life outside the womb. The lungs begin to expand and contract, preparing the muscles for breathing.
While development usually follows this normal pattern, there are times when problems with prenatal development occur. Disease, malnutrition, and other prenatal influences can have a powerful impact on how the brain develops during this critical period.
A Word From Verywell
Brain development does not end at birth. A considerable amount of brain development takes place postnatally, including growing in size and volume while changing in structure. The brain quadruples in size between birth and preschool. As children learn and have new experiences, some networks in the brain are strengthened while other connections are pruned.
The process of prenatal development occurs in three main stages. The first two weeks after conception are known as the germinal stage, the third through the eighth week is known as the embryonic period, and the time from the ninth week until birth is known as the fetal period.What develops during the fetal period? ›
Blood cells, kidney cells, and nerve cells all develop. The embryo grows rapidly, and the baby's external features begin to form. Your baby's brain, spinal cord, and heart begin to develop. Baby's gastrointestinal tract starts to form.How does a baby develop during the three trimesters of pregnancy? ›
In the first trimester, your baby will grow from a fertilized egg into a moving fetus with eyes, ears, and working organs. In the second trimester, your baby's features develop and you may be able to feel your baby move. In the third trimester, your baby will grow rapidly to get ready for birth.What can you say about prenatal period? ›
The prenatal period is the period of time before birth. A woman's nutritional needs are high during this time. Because a woman may not know that she is pregnant, she may be poorly nourished. She may also consume alcohol or caffeine in excess, which may affect the growing embryo or fetus.How does life begin in prenatal development? ›
Life Begins at Fertilization with the Embryo's Conception. "Development of the embryo begins at Stage 1 when a sperm fertilizes an oocyte and together they form a zygote." "Human development begins after the union of male and female gametes or germ cells during a process known as fertilization (conception).What is the most important stage of prenatal development? ›
The embryonic period is the most critical period of development because of the formation of internal and external structures. The critical periods of development for the organs are also discussed in the section on specific organ development.How a baby is formed step by step? ›
During fertilization, the sperm and egg unite in one of the fallopian tubes to form a zygote. Then the zygote travels down the fallopian tube, where it becomes a morula. Once it reaches the uterus, the morula becomes a blastocyst. The blastocyst then burrows into the uterine lining — a process called implantation.What's the process of making a baby? ›
The sperm and uterus work together to move the sperm towards the fallopian tubes. If an egg is moving through your fallopian tubes at the same time, the sperm and egg can join together. The sperm has up to six days to join with an egg before it dies. When a sperm cell joins with an egg, it's called fertilization.Why is prenatal development important? ›
Our health and wellbeing prenatally and during the first three years of life affect all future learning, behavior, and health. This time period is the most sensitive for a child's developing brain and body, yet many families face substantial challenges during these years.What happens to the baby during the second trimester? ›
Fetal development during the second trimester includes the following: The fetus kicks, moves and can turn from side to side. The eyes have been gradually moving to the front of the face, and the ears have moved from the neck to the sides of the head. The fetus can hear your voice.
During pregnancy, the lining of your uterus thickens and its blood vessels enlarge to provide nourishment to the fetus. As pregnancy progresses, your uterus expands to make room for the fetus. By the time your baby is born, your uterus will have expanded to many times its normal size.What happens when pregnant? ›
Your heartbeat and breathing rate are faster. Your breasts become tender, larger and heavier. Your growing uterus puts pressure on your bladder, so you feel like you need to urinate a lot. You may feel swinging moods.Why is prenatal care important and what are some good examples? ›
Prenatal care allows doctors to spot problems like anemia or gestational diabetes. Then, treatment can ensue. Prenatal care is an opportunity for the mother to learn more about labor and delivery. Knowing what to expect can put a mother's mind at ease and help her decide on the best plan for her and her baby.What is prenatal advice explain in detail? ›
Prenatal care is the health care you get while you are pregnant. It includes your checkups and prenatal testing. Prenatal care can help keep you and your baby healthy. It lets your health care provider spot health problems early. Early treatment can cure many problems and prevent others.What is the characteristics of prenatal development? ›
All the essential features of the body, both external and internal, are established. The embryo begins to turn in the uterus, and there is spontaneous movement of the limbs. The placenta, the umbilical cord, and the amniotic sac develop; these protect and nourish the embryo.What is prenatal development and explain the process of fertilization? ›
Prenatal development is defined as the process of growth and development within the womb from fertilization until birth. During this process, the zygote grows into an embryo and then a fetus.Where does a baby develop before being born? ›
Inside the uterus, the blastocyst implants in the wall of the uterus, where it develops into an embryo attached to a placenta and surrounded by fluid-filled membranes.What are the stages of development from prenatal to adolescence? ›
- Prenatal Development (conception through birth)
- Infancy and Toddlerhood (birth through two years)
- Early Childhood (3 to 5 years)
- Middle Childhood (6 to 11 years)
- Adolescence (12 years to adulthood)
For a woman with a regular period, conception typically occurs about 11-21 days after the first day of the last period. Most women do not know the exact date of conception because it can be challenging to know exactly when ovulation occurs.What is prenatal development simple? ›
prenatal development, also called antenatal development, in humans, the process encompassing the period from the formation of an embryo, through the development of a fetus, to birth (or parturition).
Your developing fetus has already gone through a few name changes in the first few weeks of pregnancy. Generally, it's called an embryo from conception until the eighth week of development. After the eighth week, it's called a fetus until it's born.What happens to the baby during the third trimester? ›
During the third trimester, your fetus continues to grow in size and weight. The lungs are still maturing, and the fetus begins to position itself head down. By the end of the third trimester, the fetus is about 19 to 21 inches long and weighs, on average, 6 to 9 pounds.Can pregnant lady cut hair? ›
Some will even tell you that your baby could have poor vision if you cut your hair while pregnant. The fact is that when a baby is born, it takes some time for their full visual ability to develop. Your haircut certainly has nothing to do with it.Can u discharge if your pregnant? ›
Increased levels of the hormones progesterone can also make you produce more fluid. Increased discharge is a normal part of pregnancy, but it's important to keep an eye on it and tell your doctor or midwife if it changes in any way.Who is pregnant woman? ›
Pregnancy is the term used to describe the period in which a fetus develops inside a woman's womb or uterus. Pregnancy usually lasts about 40 weeks, or just over 9 months, as measured from the last menstrual period to delivery.How can I sleep with my husband during pregnancy? ›
- Side-lying positions: Lying on your side is often the most comfortable, whether you're facing front-to-front or front-to-back. ...
- Pregnant partner on top: This position doesn't put any pressure on your belly, and as an added bonus, it lets you be in control of both penetration depth and clitoral stimulation.
- Take a prenatal vitamin.
- Exercise regularly.
- Write a birth plan.
- Educate yourself.
- Change your chores (avoid harsh or toxic cleaners, heavy lifting)
- Track your weight gain (normal weight gain is 25-35 pounds)
- Get comfortable shoes.
- Eat folate-rich foods (lentils, asparagus, oranges, fortified cereals)
Prenatal care can help keep you and your baby healthy. Babies of mothers who do not get prenatal care are three times more likely to have a low birth weight and five times more likely to die than those born to mothers who do get care. Doctors can spot health problems early when they see mothers regularly.What is the most important part of prenatal care? ›
Following a healthy, safe diet; getting regular exercise as advised by a health care provider; and avoiding exposure to potentially harmful substances such as lead and radiation can help reduce the risk for problems during pregnancy and promote fetal health and development.What are three things that are required for prenatal care? ›
The three main components of prenatal care are risk assessment, health promotion and education, and therapeutic intervention . High-quality prenatal care can prevent or lead to timely recognition and treatment of maternal and fetal complications.
Prenatal development is defined as the process of growth and development within the womb from fertilization until birth. During this process, the zygote grows into an embryo and then a fetus.What is the prenatal period of development quizlet? ›
Prenatal development proceeds through the germinal (first 2 weeks), embryonic (2 weeks to 2 months), and fetal stages (2 months to birth) as the zygote is differentiated into a human organism. The embryonic stage is a period of great vulnerability, as most physiological structures are being formed.Why is prenatal development so important? ›
Our health and wellbeing prenatally and during the first three years of life affect all future learning, behavior, and health. This time period is the most sensitive for a child's developing brain and body, yet many families face substantial challenges during these years.What is the importance of prenatal period? ›
Prenatal care is the healthcare you receive while pregnant. Regular prenatal care throughout your pregnancy helps to catch potential concerns early and reduces the risk of pregnancy and birth complications. As soon as you suspect you are pregnant, make an appointment with your OB/Gyn.Which is the correct order of prenatal development quizlet? ›
The correct sequence of prenatal development is: germinal period, embryonic period, fetal period.What are the factors that influence prenatal development? ›
- Preconceptional factors.
- Exposure to toxins.
- Maternal chronic illness.
- Maternal nutritional deficiencies.
The germinal stage is the first stage of prenatal development. Conception is the event that occurs two weeks after fertilization. Cleavage is the early stages of cell division during prenatal development. A zygote is the term used for a developing baby from the time of fertilization until implantation.