Decidual

Decidua
Details
Precursor	Endometrium
System	Reproductive system
Identifiers
Latin	Decidua
TA98
TH	{{#property:P1694}}
TE	{{#property:P1693}}
FMA	{{#property:P1402}}
Anatomical terminology

The decidua is the modified mucous membrane of the endometrium (lining of the uterus) that forms in preparation for pregnancy. It is a critical component in the support of the developing embryo in mammals during early gestation. The decidua forms after the ovulation phase when the endometrial cells undergo significant changes, both morphologically and functionally, in a process known as decidualization.

Structure

The decidua is divided into three distinct layers during pregnancy:

• Decidua basalis - the part directly under the implantation site of the embryo, which later develops into the maternal part of the placenta.
• Decidua capsularis - the part overlying the embryo, expanding as the embryo and gestational sac grow.
• Decidua parietalis - all other remaining parts of the decidua, lining the rest of the uterus.

Function

The primary function of the decidua is to protect and nutritionally support the embryo. It secretes a variety of hormones and other factors that are essential for maintaining the pregnancy. The decidua also plays a role in the immune tolerance of the fetus, a crucial factor for a successful pregnancy.

Clinical Significance

Abnormalities in decidualization can lead to pregnancy complications such as ectopic pregnancy, miscarriage, and preeclampsia. The study of the decidua is important in understanding and potentially treating these conditions.

See Also

• Endometrium
• Pregnancy
• Placenta
• Embryo