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 officially becomes a...
The development of a single cell into a small but identifiable human being in only 12 weeks is amazing to observe. The merging of two single cells, the sperm and the egg, starts a cascade of cell division, differentiation and growth that results...
Pregnancy lasts around 40 weeks. These are grouped into three stages known as trimesters, each of which lasts between 12 and 16 weeks. Notable changes take place in both your and your baby's body during each trimester. Each pregnancy is different....
Many people, including pregnant women, wonder when exactly a fetus becomes a baby. By "baby," they frequently mean a full-fledged, if very young and small, human being or human person. Embryology, the science of prenatal development, distinctly...
A human fetus develops over the course of about 38 weeks of pregnancy. This developmental process follows a precisely ordered and timed set of stages. Scientists have characterized these stages in enough detail to fill several books. Several...
During the 38 to 42 weeks of a typical pregnancy, a fetus develops in the mother's womb. The mother's egg is fertilized by the father's sperm to produce a single cell called the zygote. This develops into a ball of several hundred cells called the...
Conception occurs when a sperm meets with and fertilizes an ovum, or egg, that is traveling down the fallopian tube. The result is a one-celled entity called a zygote. A zygote normally has 46 chromosomes; 23 from the mother and 23 from the...
When the mother's egg is fertilized by sperm, it forms a single cell called a zygote. 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...
A fetus develops according to a precisely ordered and timed set of stages during a pregnancy, which on average lasts between 38 to 42 weeks. When the mother's egg is fertilized---usually in one of the mother's fallopian tubes---by the father's...
Being pregnant is a time of wonder. Both parents can become curious to what their developing baby looks like inside the womb. Luckily, the development of a fetus follows a relatively predictable course of growth. A 5-week-old fetus is developing...
Pregnancy is an exciting time for a new mother. It is natural to wonder how your baby is growing and developing as your body is drastically changing. A baby's growth during pregnancy follows a predictable course from fertilization, to the forming...
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 embryonic phase of human development lasts from two weeks after conception--during the first two weeks, the fertilized egg is referred to as a zygote--until the end of the eighth week of pregnancy, at which time the embryo becomes a fetus....
Beginning the moment that a sperm fertilizes an egg, a baby begins to grow in the womb. As it goes through the various stages of development, it grows from being nothing more than tiny cells into a baby that will hopefully be loved and cherished.
Pregnancy due dates are calculated by adding 40 weeks to the date of your last menstrual period. Technically, during the first two weeks of this time frame, most women are not yet pregnant. Fertilization occurs at week three when the sperm and egg...
Prenatal vitamins are daily supplement pills formulated for pregnant women. They don't contain calories, so they can't foster cellular growth, but they're important to cellular health and well being. While they don't help your embryo grow fast,...
If you have experienced the miracle of birth, you may also have wondered just what goes on inside a woman's body during pregnancy. From conception to birth typically takes nine months; plenty of time for organs and bones to develop. Birth may be a...
At six weeks, some doctors perform a sonogram, also called an ultrasound, to determine the health or viability of the developing embryo. This is generally the earliest that anything is visible on an ultrasound, although at this point it will not...
The first week of an embryo's life is critical to its survival. During this time, the embryo must undergo genetic, metabolic and developmental changes that allow for implantation in the uterine lining. The mother's menses will cease, and...
From the moment of conception, rapid cellular division begins and initiates the start of a child's development in the womb. The developing embryo will go through many changes. From the development of organs and bones to eyes, ears, and tiny feet...
Detection of a normal heartbeat in an unborn baby is one measure of the overall health of the pregnancy. An unborn baby has a heartbeat very early in the pregnancy, when the fetus is still in the embryonic stage. Exactly when a doctor can detect a...
It's around the fourth week of gestation when a pregnancy test typically confirms your suspicions. While you have may have been wondering whether or not you are pregnant, your uterus has been busy at work creating a safe and nurturing environment...
Pregnancy is divided into three developmental stages: the first trimester, or first three-month period; the second trimester, from three to six months; and the third trimester, from six to nine months, according to the University of Iowa. Each...
Pregnancy and the development of a child is an amazing process. During the 40 weeks of pregnancy one single cell transforms into a human being. Throughout this transformation there are many identifiable stages. The early stages of pregnancy take...
During pregnancy, the unborn child goes through several stages of development. The baby begins as nothing more than a single-cell organism, and with each stage, he progresses until he becomes a human being who is completely developed and able to...
The development of the human being is a dynamic process. Shortly after conception, the cells that make up the developing embryo will differentiate into three distinct tissue types known as germ layers: endoderm, mesoderm and ectoderm. Heart...
Physical development in humans is the process whereby cells differentiate into different types and tissues, develop function and ultimately begin to perform these given functions. Development begins at conception, and continues up through puberty,...
Pregnancy consists of three stages called trimesters. Most healthy pregnancies progress at approximately the same rate, but many variables can affect fetal development during each trimester. For this reason, the American Pregnancy Association...
The first 12 weeks of pregnancy, known as the first trimester, abound with changes and growth in your unborn baby. Despite a common misconception, you don't get pregnant the instant semen enters your body. It takes up to two weeks for the process...
