Jump to navigation Jump to search

Template:Infobox Embryology

WikiDoc Resources for Trophoblast


Most recent articles on Trophoblast

Most cited articles on Trophoblast

Review articles on Trophoblast

Articles on Trophoblast in N Eng J Med, Lancet, BMJ


Powerpoint slides on Trophoblast

Images of Trophoblast

Photos of Trophoblast

Podcasts & MP3s on Trophoblast

Videos on Trophoblast

Evidence Based Medicine

Cochrane Collaboration on Trophoblast

Bandolier on Trophoblast

TRIP on Trophoblast

Clinical Trials

Ongoing Trials on Trophoblast at Clinical

Trial results on Trophoblast

Clinical Trials on Trophoblast at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Trophoblast

NICE Guidance on Trophoblast


FDA on Trophoblast

CDC on Trophoblast


Books on Trophoblast


Trophoblast in the news

Be alerted to news on Trophoblast

News trends on Trophoblast


Blogs on Trophoblast


Definitions of Trophoblast

Patient Resources / Community

Patient resources on Trophoblast

Discussion groups on Trophoblast

Patient Handouts on Trophoblast

Directions to Hospitals Treating Trophoblast

Risk calculators and risk factors for Trophoblast

Healthcare Provider Resources

Symptoms of Trophoblast

Causes & Risk Factors for Trophoblast

Diagnostic studies for Trophoblast

Treatment of Trophoblast

Continuing Medical Education (CME)

CME Programs on Trophoblast


Trophoblast en Espanol

Trophoblast en Francais


Trophoblast in the Marketplace

Patents on Trophoblast

Experimental / Informatics

List of terms related to Trophoblast

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]


Trophoblasts (from Greek threphein: to feed) are cells forming the outer layer of a blastocyst, which provide nutrients to the embryo and develop into a large part of the placenta. They are formed during the first stage of pregnancy and are the first cells to differentiate from the fertilized egg.


Trophoblasts are invasive, eroding, and metastasizing cells of the placenta.

Trophoblasts mediate the implantation of the embryo into the endometrium, but they are never incorporated into the mother's body or the fetus. They are not "fetal" cells.

Trophoblasts become inert during pregnancy and are completely rejected by the fetus and mother at delivery. They can be seen as the thin membrane covering the fetus at birth, the caul.[1]


The trophoblast proliferates and differentiates into 2 cell layers:

Layer Location Description
cytotrophoblast inner layer Single celled layer adjacent to trophoblast.
syncytiotrophoblast outer layer Thick layer that lacks cell boundaries and grows into the endometrial stroma. It secretes hCG in order to maintain progesterone secretion and sustain a pregnancy.


The invasion of a specific type of trophoblast (extravillous trophoblast) into the maternal uterus is a vital stage in the establishment of pregnancy:

  • Failure of the trophoblast to invade sufficiently may be important in the development of some cases of pre-eclampsia.
  • Too firm an attachment may lead to placenta accreta.

Additional images

See also


External links



Template:WikiDoc Sources