Decidua

Jump to navigation Jump to search

Template:Infobox Anatomy

WikiDoc Resources for Decidua

Articles

Most recent articles on Decidua

Most cited articles on Decidua

Review articles on Decidua

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

Media

Powerpoint slides on Decidua

Images of Decidua

Photos of Decidua

Podcasts & MP3s on Decidua

Videos on Decidua

Evidence Based Medicine

Cochrane Collaboration on Decidua

Bandolier on Decidua

TRIP on Decidua

Clinical Trials

Ongoing Trials on Decidua at Clinical Trials.gov

Trial results on Decidua

Clinical Trials on Decidua at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Decidua

NICE Guidance on Decidua

NHS PRODIGY Guidance

FDA on Decidua

CDC on Decidua

Books

Books on Decidua

News

Decidua in the news

Be alerted to news on Decidua

News trends on Decidua

Commentary

Blogs on Decidua

Definitions

Definitions of Decidua

Patient Resources / Community

Patient resources on Decidua

Discussion groups on Decidua

Patient Handouts on Decidua

Directions to Hospitals Treating Decidua

Risk calculators and risk factors for Decidua

Healthcare Provider Resources

Symptoms of Decidua

Causes & Risk Factors for Decidua

Diagnostic studies for Decidua

Treatment of Decidua

Continuing Medical Education (CME)

CME Programs on Decidua

International

Decidua en Espanol

Decidua en Francais

Business

Decidua in the Marketplace

Patents on Decidua

Experimental / Informatics

List of terms related to Decidua

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

Overview

Decidua is the term for the uterine lining (endometrium) during a pregnancy, which forms the maternal part of the placenta. It is formed under the influence of progesterone and forms highly-characteristic cells.

Etymology

The word comes from the Latin deciduus, meaning falling off or shedding.

Background

After ovulation, in mammals, the endometrial lining becomes transformed into a secretory lining in preparation of accepting the embryo. Without implantation, the secretory lining will be absorbed (estrous cycle) or shed (menstrual cycle).

With implantation the lining now termed decidua evolves further during the pregnancy.

The decidua is shed during the parturition process.

Structure

Different layers of the deciduas have been described:

  • a compact outer layer (stratum compactum)
  • an intermediate layer (stratum spongiosum)
  • a boundary layer adjacent to the myometrium.

That part of the decidua that interacts with the trophoblast is the decidua vera (“true decidua”). The remainder of the decidua is termed the decidua parietalis.

The decidua has a histologically-distinct appearance, displaying large polygonal decidual cells in the stroma. These are enlarged endometrial stromal cells, which resemble epithelium (and are referred to as "epithelioid").

Formation of a specialized decidua is called decidualization, which is a special property of endometrium seen only in hemochorial placentation.

Decidualization includes the process of differentiation of the spindle-shape stromal fibroblasts into the plump secretory decidual cells, which create a pericellular extracellular matrix rich in fibronectin and laminin (similar to epithelial cells).

Vascularity, as well as vascular permeability, is enhanced in the decidualizing endometrium.

Its leukocyte population is distinct, with the presence of large endometrial granular leukocytes being predominant, while polynuclear leukocytes and B-cells are scant.

The large granular lymphocytes (CD56 bright) are called "uterine NK cells" or "uNK cells" in mice, and "decidual NK cells" or "dNK cells" in humans.

The border to the trophoblast is called Nitabuch’s layer.

Role

As the maternal interface to the embryo the decidua participates in the exchanges of nutrition, gas, and waste with the gestation. It also protects the pregnancy from the maternal immune system. Further, the decidua has to allow a very controlled invasion of the trophoblast.

In invasive placental disorders like placenta accreta decidualization have been consistently found to be deficient.

Hormone production

The decidua secretes hormones, growth factors, and cytokines. It has receptors for estrogen, progesterone, growth hormone, and others.

Among its products are hormones commonly associated with other organs such as cortisol, CRF, GnRH, prolactin, and relaxin. Decidual prolactin is not under dopaminergic control.

Pregnancy protein 14 (PP-14), also called placental protein 12, and Insulin-like growth factor-binding protein 1(IGFBP1) appear to be specific products of the secretory and decidual lining.

Other factors released include interleukin-15 and vascular endothelial growth factor (VEGF). A reasonable understanding of the role and interplay of these hormones and factors has not been evolved.

Other

  • In case of an extrauterine pregnancy, the endometrium nevertheless becomes decidualized. A woman may shed the lining in the form of a decidual cast, which may be mistaken as a miscarriage, when, in fact, the ectopic still persists.
  • A decidual reaction can be observed in tissue of the peritoneum and ovary during a pregnancy, and represents a response of stromal tissue to progesterone.

Additional images

See also


Template:WH Template:WikiDoc Sources