There are three stages of prenatal development: germinal, embryonic, and fetal .
What are the 3 major stages of prenatal development?
This union marks the beginning of the prenatal period, which in humans encompasses three distinct stages: (1) the pre-embryonic stage, the first two weeks of development, which is a period of cell division and initial differentiation (cell maturation), (2) the embryonic period, or period of organogenesis, which lasts ...
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.
What is meant by prenatal development?
Prenatal development: The process of growth and development within the womb , in which a single-cell zygote (the cell formed by the combination of a sperm and an egg) becomes an embryo, a fetus, and then a baby. The first two weeks of development are concerned with simple cell multiplication.
What are the 5 stages of prenatal development?
- Germinal Stage.
- Embryonic Stage.
- Fetal Stage.
How long is prenatal development?
Prenatal development starts at conception and ends with the birth of your baby. It takes about 40 weeks or nine months to create a new life, and your pregnancy is broken into three, 12-week trimesters.
What are the developmental stages?
There are three broad stages of development: early childhood, middle childhood, and adolescence . They are defined by the primary tasks of development in each stage.
What are the factors that affect prenatal development?
Prenatal risk factors include chronic maternal illness, certain maternal infections, toxin exposures and nutritional deficiencies . Risk factors in the perinatal period include pregnancy-related complications, prematurity and low birth weight, and infection exposure during pregnancy or at time of birth.
What are the major milestones in pregnancy?
This is when organ development begins, lasting approximately six weeks. 5 weeks: The baby’s heart begins to beat, generally at about twice the rate of an adult heart. 6 weeks: Facial features begin to form, and little buds for the arms and legs start to develop. 10 weeks: The embryo officially becomes a fetus .
What is germinal period?
The germinal period ( about 14 days in length ) lasts from conception to implantation of the zygote (fertilized egg) in the lining of the uterus. During the first week after conception, the zygote divides and multiplies, going from a one-cell structure to two cells, then four cells, then eight cells, and so on.
Which trimester is the most critical for fetal development?
The first trimester is the most crucial to your baby’s development. During this period, your baby’s body structure and organ systems develop. Most miscarriages and birth defects occur during this period. Your body also undergoes major changes during the first trimester.
What are 3 environmental factors that affect prenatal development?
Various teratogens include drugs, alcohol, tobacco, and other environmental agents. The adverse effects of a teratogen depend on several factors, such as the dose or level of exposure, heredity, age of the teratogen, and any other negative influences .
What are 4 environmental factors that can harm a fetus?
Environmental factors which have been implicated in adverse pregnancy outcome include smoking, video display terminals, anesthetic gases, antineoplastic drugs and exposure to lead, selenium and inorganic mercury .
What are 3 things a female should avoid while she is pregnant?
- Certain foods. Share on Pinterest. ...
- Wet paint. Share on Pinterest. ...
- Caffeine. Share on Pinterest. ...
- Certain medications. Share on Pinterest. ...
- Stilettos. ...
- Hot tubs and saunas. ...
- Kitty litter. ...
- Secondhand smoke.
How do I know if my baby is developing normally in the womb?
An ultrasound is usually done for all pregnant women at 20 weeks. During this ultrasound, the doctor will make sure that the placenta is healthy and attached normally and that your baby is growing properly. You can see the baby’s heartbeat and movement of its body, arms, and legs on the ultrasound.
What is the last organ to form in a fetus?
Almost all organs are completely formed by about 10 weeks after fertilization (which equals 12 weeks of pregnancy). The exceptions are the brain and spinal cord , which continue to form and develop throughout pregnancy. Most malformations (birth defects) occur during the period when organs are forming.
