There are two processes by which fetuses form bone. One depends upon the presence of a cartilage model, while the other does not. Ossification, or replacement of the cartilage model with bone, isn't completed at the time of birth. This allows some flexibility in the skeleton of a newborn, which helps prevent skeletal trauma during birth. There are a number of maternal factors that can affect development of fetal bone, including maternal vitamin and mineral status, which refers to whether the mother has adequate quantities of vitamins and...
When you have an alcoholic beverage, a cigarette or abuse prescription or illegal drugs, your baby feels the effects. No safe amount of alcohol, tobacco or drugs exists during pregnancy. Drugs and alcohol can affect fetal devel...
From the beginning to the end of your pregnancy, your baby will develop rapidly, changing from a microscopic zygote into a full-term baby in approximately 40 weeks. You may be eager to begin feeling the kicks and flutters that ...
As a pregnant woman, you know that the foods you eat and the substances you are exposed to can influence your baby's growth and development. If you consume caffeine during pregnancy, your baby may experience certain problems wi...
Alcohol passes easily through the mother's bloodstream into the fetus, causing the fetus' blood alcohol level to match or exceed that of its mother. Even moderate drinking is associated with an increased risk of birth defects r...
Her blood supply provides it with what it needs to grow during gestation. If the mother does not receive adequate nutrition, the fetus will grow more slowly and is more likely to be underweight at birth. It can also be underdev...
However, caffeine can also affect your growing baby. Your body breaks down caffeine more slowly as your pregnancy progresses, so it can start to build up in your bloodstream as well as your baby's. It is important to understand...
The brain is a highly complex structure with the same nutritional requirements as most other structures in the body. However, there are specific nutrients needed by the brain in order for it to function normally. Vitamins are o...
The fetal brain begins its development within weeks of conception, a process that proceeds not only during the nine months of pregnancy but continues into adulthood. The mother's nutrition during pregnancy affects the developin...
Fertilization occurs at week three when the sperm and egg unite to form a zygote in the fallopian tube. By week four, the zygote, now called a blastocyst, will make its way to the uterine wall and a placenta will begin to develop.
Pregnant women must gain weight. Fetal growth and development, as well as maternal health, depend on it, according to Eleanor Whitney and Sharon Rolfes in "Understanding Nutrition." During pregnancy, diet is extremely important...
A baby goes through tremendous growth and development during its 40 weeks in a mother's uterus. With so many changes occurring, prenatal care is essential to monitor the health of the baby and the mother to ensure a healthy pre...
Department of Health and Human Services. This time span is around the end of the seventh month and the beginning of the eighth month of pregnancy, a time when the child is moving more forcefully and developing at a rapid rate. ...
Rapid development occurs inside the womb as a single cell forms into an embryo, fetus and then a baby. You may find yourself wondering about your baby's fetal development as she grows and forms external and internal features.
A fetus passes through seven stages of development during the 42 weeks of a pregnancy. During those 42 weeks, the mother experiences the development, too, as her body changes. Many permanent features form during the first two w...
In nine months, a future human being develops from a ball of cells into a baby. Fetal development follows a well-documented chronology and is divided into trimesters.
Human pregnancy lasts an average of 36 weeks from the time of conception to birth. The stages of prenatal development are generally classified into two time periods, the embryonic and fetal periods. The embryonic period ends at...
Pregnancy is divided into three trimesters, each lasting about 12 to 14 weeks. The pregnancy then progresses through the stages needed to help the baby develop and mature so that he is ready to be born and survive outside his m...
Lung development in a fetus starts during the embryonic phase, at around four weeks of gestational age. Very early in development, what will eventually be a baby is nothing more than a cell ball, where none of the cells are yet...
The fetal stage of development lasts from the end of the second month, or eighth week, until the end of the fortieth week. While all organs and organ systems are in place by the beginning of the fetal stage of development, this...
The result is a one-celled entity called a zygote. A zygote normally has 46 chromosomes; 23 from the mother and 23 from the father. Chromosomes are a fetus's genetic code. This genetic code will determine a baby's sex, eye co...
By the time the heart is able to be heard when amplified by fetal Doppler, around nine to ten weeks of pregnancy, says the Dr. Spock website, the heart has already fully formed, with four chambers, two atria and two ventricles,...
Fetal development begins the moment the egg and sperm meet. These early days and weeks form the foundation for the unborn baby, who will change exponentially in the months from conception until birth. Early fetal development en...
Fetal development begins seconds after the egg is fertilized and the fertilized egg contains its complete and distinct DNA. Every gene that the baby will carry for its lifetime is immediately present. The pregnancy is composed ...
Fetal development begins before a pregnancy may even be noticed, and the fetus undergoes rapid development in the 40 weeks of gestation spent in the mother's uterus. According to the University of Maryland Medical Center, the t...
The zygote grows into a ball of cells called a blastocyst and embeds itself into the wall of the mother's uterus. Over the subsequent two weeks, it becomes an embryo, and by week eight of the pregnancy the fetal stage of develo...
After being fertilized, the zygote divides and replicates itself rapidly, forming a ball of several hundred cells called a blastocyst. The blastocyst embeds itself in the wall of the mother's uterus and develops into an embryo ...
Fetus development proceeds over the course of 38 to 42 weeks of pregnancy. During that time, the fetus develops from a single, fertilized cell---called a zygote---into a full-term fetus, ready to be born and live outside the wo...
This single cell develops into a ball of cells called the blastocyst, and then an embryo over the following two weeks. During week eight, it becomes a fetus. Over the following 30 to 34 weeks, continued development prepares the...
During a 38-week pregnancy, one fertilized egg cell develops into a fetus that is soon ready to become a newborn baby. The process of fetal development consists of a set of stages that unfold with consistent order and timing. F...
Over the course of approximately 38 weeks, a fertilized egg grows from zygote to embryo to fetus. The development that takes place before birth--referred to as prenatal development--follows a set of steps that are very consiste...
The creation of new life is an amazing event, but one that does not happen overnight. That cute little bundle of joy in the arms of his parents went through many different developmental stages. Prior to entering the world, the ...
Although a new embryo is too small to see in an ultrasound, science and technology can give an idea about what the embryo looks like and how it is developing. As an unborn baby grows inside the womb, ultrasound technology can s...
The period of human development before birth is known as the prenatal stage and is divided into three sections---the germinal period, the embryonic period and the fetal period. During the germinal period, which begins with fert...
Pregnancy, while an exciting time in your life, can also leave you on the edge of your seat as you wonder how your baby is growing and developing inside you. Just as you mark each of his developmental milestones once he is born...
From the initial embryonic stage in which the fetus is entirely dependent on the mother for survival, a fetus develops into an incredibly complex organism capable of surviving on its own. Fetal development can be divided into d...
When a woman becomes pregnant, her body changes in many ways as she awaits the birth of her baby. Within the uterus, the fetus goes through several stages of development. Over a period of approximately 40 weeks, your baby will ...
Although you're barely showing much in the way of a baby bump, your baby is working day and night on his development, and already has all of the necessary tissues and organs that he'll need outside of the womb. While you can't ...
At the time of a missed period, a woman is considered to be four weeks pregnant. Early signs of pregnancy can only be detected by blood tests or by ultrasound. Around six weeks, the fetal pole, which is the first part of the hu...
During the course of pregnancy, nature takes a microscopic dot of life and creates a 7 lb. baby in only nine months. Fetal development is explosive, particularly in the first few months.
The skeleton of the fetus begins developing bones about 13 weeks following conception. The bones gradually become harder and muscle tissue begins to develop. At birth, a newborn's body has approximately 300 bones. Over time, th...
Embryonic growth is rapid and complex. The basic organs and nervous system evolves, including the brain, heart, gastrointestinal tract and spine. By week six, a vaginal ultrasound may reveal a fetal heartbeat. By week eight, th...
Pregnancy is divided into trimesters, and a full-term pregnancy is 40 weeks. It's normal to wonder about the growth of your fetus and his formation, and what bodily changes are happening when. From sperm and egg meeting to a fu...
The first stage of a fetus begins toward the end of the first trimester of pregnancy. During the first 9 weeks of development, the growing baby is referred to as an embryo. In week 10, at the end of the first trimester, it offi...
Although a pregnancy starts as soon as fertilization occurs, it is at the ninth week that the baby growing inside is referred to as a fetus. Before this time, the fetus has been referred to as a blastocyst, zygote, morulla and ...
Facial features begin to appear, as well as the passageways that will form the inner ear and the arches that will form the jaw. Stubs show up that will become arms and legs. The nostrils and eyes begin developing in Week 7, and...
During the first trimester, or the first 12 weeks of pregnancy, your baby goes from a separate egg and sperm cell to a recognizable boy or girl with skin and bones that may even be sucking his thumb. Other developments during t...
According to the National Institutes of Health (NIH), an embryo becomes a fetus in its ninth week of development. Between its ninth and 20th weeks, it has long, thin limbs and a well-defined face. Its genitals are defined, and ...
It is actually a mucous membrane that is part of the vulva, the external genital organs. It is formed from a layer of tissue that develops in the early stages of fetal development when there is no opening in the vagina at all. ...
