Decidua

The uterine lining that forms the maternal part of the placenta.

Last updated 5 November 2026

The decidua is the modified mucosal lining of the uterus that forms each month in preparation for pregnancy. It is shed when no fertilized egg is present and, during pregnancy, forms the maternal part of the placenta. The decidua remains throughout gestation and is expelled after birth together with the placenta.

Quick Facts

Layers of decidua basalis

three morphologically distinct layers: stratum compactum
stratum spongiosum
stratum basalis

Fibrinoid layer names

Rohr's layer and Nitabuch's layer

Predominant leukocyte type

large endometrial granular leukocytes (uterine natural killer cells, CD56 bright)

Specific products

IGFBP1 (placental protein 12) and PAEP (glycodelin)

Facts from the source article.

Did You Know?

After ovulation, the endometrial lining becomes hypertrophic and vascular under the influence of estrogen and progesterone.
In animals with hemochorial placentation, the endometrium undergoes decidualization following implantation.
If implantation does not occur, the secretory lining is absorbed (estrous cycle) or shed (menstrual cycle).

More in Obstetrics

Delayed cord clamping (DCC)Doppler fetal monitor Early postnatal hospital discharge Echogenic intracardiac focus Etiology, Concept and Prophylaxis of Childbed Fever Ferguson reflex Fetal head Fetal heart rate Fetal heart tones Final maturation induction Obstetrics Outline of obstetrics

Sources

Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.

Wikipedia: Decidua (CC BY-SA 4.0).
Word definitions: the Codexery glossary, each quoted from its Wikipedia article.

Spotted an error? Know more?

Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced

Comments

Loading…

Open in the interactive codex →