prenatal development

Table of Contents

Introduction
Pre-embryonic and embryonic development
- Fertilization
- Cleavage and blastulation
- Implantation and placentation
  - Implantation
  - Placentation
- Extra-embryonic membranes
  - Yolk sac
  - Amnion
  - Allantois
  - Umbilical cord
- Formation of the three primary germ layers
- Growth and differentiation
- Embryonic acquisition of external form
  - Development between the second and fourth weeks
  - Developmental changes in the fifth to eighth weeks
Fetal development
Development of organs
- Ectodermal derivatives
  - Integumentary system
  - Mouth and anus
  - Central nervous system
    - Brain
    - Spinal cord
  - Peripheral nervous system
    - Spinal nerves
    - Cranial nerves
  - Autonomic nervous system
  - Sense organs
    - Olfactory organ
    - Gustatory organ
    - Eye
    - Ear
- Mesodermal derivatives
  - Skeletal system
    - Axial skeleton
    - Appendicular skeleton
    - Articulations
  - Muscular system
  - Vascular system
    - Blood vessels
    - Lymphatic vessels
    - Heart
  - Urinary system
  - Genital system
    - Gonads
    - Genital ducts
    - External genitalia
  - Coelom
- Endodermal derivatives
  - Pharynx
  - Digestive tube
  - Major glands
  - Respiratory system
    - Nasal cavity
    - Larynx, trachea, and lungs
Abnormal development
- Multiple births
- Fetal deviations
- Teratology

References & Edit History Quick Facts & Related Topics

Images & Videos

human fetus; prenatal development

How a human embryo develops into a fetus

embryos of different animals

first stages of human development

implanted human embryo

human embryonic development

human embryonic development

formation of the neural tube in prenatal development

umbilical cord formation

Discover

Thanksgiving Turkey with all the sides

Why Do We Eat Turkey on Thanksgiving?

Super Typhoon Noru over the western tropical Pacific Ocean as observed by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA Aqua satellite July 31 2017

What Is the Difference Between a Typhoon and a Super Typhoon?

A human Inuit skull in a stone chambered cairn in Ilulissat in Greenland. These ancient graves are pre christian and are at least 2000

14 Tough Questions Answered

An ancient egyptian hieroglyphic painted carving showing the falcon headed god Horus seated on a throne and holding a golden fly whisk. Before him are the Pharoah Seti and the goddess Isis. Interior wall of the temple to Osiris at Abydos, Egypt.

11 Egyptian Gods and Goddesses

Los Angeles Police Department wanted flyer on Elizabeth Short, aka the "Black Dahlia," who was brutally murdered in January 1947. The FBI supported the Los Angeles Police Department in the case, including by identifying Short through her fingerprints that

America’s 5 Most Notorious Cold Cases (Including One You May Have Thought Was Already Solved)

A Factory Interior, watercolor, pen and gray ink, graphite, and white goache on wove paper by unknown artist, c. 1871-91; in the Yale Center for British Art. Industrial Revolution England

Inventors and Inventions of the Industrial Revolution

Rural Irish landscape, Sligo, Ireland.

Why Is Ireland Two Countries?

prenatal development: Media

physiology

Videos

How a human embryo develops into a fetus

How a human embryo develops into a fetus

Learn about human embryonic and fetal development from fertilization to birth.

Video: Encyclopædia Britannica, Inc.

Images

human fetus; prenatal development

human fetus; prenatal development

An ultrasound image of a human fetus.

ton koene/Alamy

embryos of different animals

embryos of different animals

The embryos of many animals appear similar to one another in the earliest stages...

Encyclopædia Britannica, Inc.

sperm

sperm

A sperm cell attempting to penetrate an egg (ovum) to fertilize it.

www.pdimages.com

first stages of human development

first stages of human development

Early stages of human development. (A–D) Cleavage of the ovum. (E–F) Blastocyst development.

Encyclopædia Britannica, Inc.

implanted human embryo

implanted human embryo

Development of the human embryo, shown as half-section depictions of embryos implanted...

Encyclopædia Britannica, Inc.

human embryonic development

human embryonic development

Development of the human embryo at 23 days.

Encyclopædia Britannica, Inc.

human embryonic development

human embryonic development

Development of the human embryo at 18 days, at disk or shield stage, shown in (left)...

Encyclopædia Britannica, Inc.

formation of the neural tube in prenatal development

formation of the neural tube in prenatal development

Cross section of the embryonic disk, showing formation of the neural tube in prenatal...

Encyclopædia Britannica, Inc.

umbilical cord formation

umbilical cord formation

Human embryological and fetal development. An embryo of six weeks is depicted within...

Encyclopædia Britannica, Inc.

embryonic development

embryonic development

The state of development of a human embryo at the seventh week of pregnancy.

Encyclopædia Britannica, Inc.

fetal growth

fetal growth

Growth of the human fetus from the fourth month to the ninth month of pregnancy.

Encyclopædia Britannica, Inc.

neural stem cells

neural stem cells

Human neural stem cells (cell nucleus shown in blue).

Prof. John Sinden

human fetal brain; prenatal development

Profile of the brain of a human fetus at 10 weeks.

Encyclopædia Britannica, Inc.

motor neuron

motor neuron

Anatomy of a nerve cell. Structural features of a motor neuron include the cell body,...

Encyclopædia Britannica, Inc.

external genitalia

external genitalia

Differentiation of the external genitalia in the human embryo and fetus.

Encyclopædia Britannica, Inc.

VIEW MORE in these related Britannica articles: