chorionic villi

(redirected from Chorionic villous)


pertaining to the chorion.
chorionic villi numerous branching projections from the external surface of the chorion that provide for exchange between the maternal and fetal circulation. Oxygen and nutrients in the maternal blood diffuse through the walls of the villi and enter the blood of the embryo or fetus. Carbon dioxide and waste products diffuse from blood in the fetal capillaries through the walls of the villi into the maternal blood. See also chorionic villus sampling.


 [vil´us] (L.)
a small vascular process or protrusion, as from the free surface of a membrane.
arachnoid villi microscopic projections of the arachnoid into some of the venous sinuses.
chorionic villi see chorionic villi.
intestinal villi multitudinous threadlike projections covering the surface of the mucous membrane lining the small intestine, serving as the sites of absorption of fluids and nutrients.
synovial villi slender projections from the surface of the synovial membrane into the cavity of a joint; called also haversian glands.

cho·ri·on·ic vil·li

vascular processes of the chorion of the embryo entering into the formation of the placenta.

cho·ri·on·ic vil·li

(kōr'ē-on'ik vil'ī)
Vascular processes of the chorion of the embryo entering into the formation of the placenta.

chorionic villi

The finger-like projections from the CHORION into the wall of the womb at the site at which the PLACENTA is developing. Since both the chorionic villi and the embryo are derived from the same fertilized ovum a sample of the former provides material for genetic studies of the latter. Chorionic villus sampling has become an important method of early pre-natal screening for genetic defects.

Chorionic villi

Microscopic, finger-like projections that emerge from the outer sac which surrounds the developing baby. Chorionic villi are of fetal origin and eventually form the placenta.
References in periodicals archive ?
With improved screening methods, there is a need for diagnostic tests such as a chorionic villous sample and amniocentesis to confirm or exclude aneuploidy.
Noninvasive Prenatal Sequencing - Successful sequencing of a human fetus through noninvasive means using amniocentesis or chorionic villous sampling which do not carry the risk of potentially harming the developing fetus.
While a positive test with this combination of markers is the optimal prediction, it still only indicates approximately one in 20 chance of having a Down-syndrome fetus, therefore chorionic villous sampling or amniocentesis is warranted to give a definitive prediction.
In this article the authors report on in vitro effects of p-NP on cytokine secretion in cultured chorionic villous explants from human placentas.
8) In conditions associated with maternal hypoperfusion the placenta may show perivillous fibrinoid deposition, subchorionic fibrinoid plaque, massive subchorial thrombosis, basal intervillous thrombus, intervillous lakes, retroplacental haematomas, maternal surface chorionic villous infarction and syncytial knots.
In our experience, the risk of maternal contamination in chorionic villous samples is remote with careful microscopic dissection to remove contaminating maternal decidua.
In some instances, multiple tissues from individual specimen were analyzed, including amniotic membrane, chorionic membrane, chorionic villous stroma, and trophoblast, as well as fetal tissues.
The breakthrough offers an opportunity for earlier prenatal screening than currently offered with amniocentesis or chorionic villous sampling (CVS) without the same risks for potentially harming a developing fetus.
METHODS: In vitro cultures of chorionic villous explants from human placenta in the first trimester of pregnancy were treated with p-NP ([10.
This is in accordance with the observed relationship between high tHcy and defective chorionic villous vascularization in mothers with recurrent early pregnancy loss (18).
Risk of mosaicism when placental mosaicism is diagnosed by chorionic villous sampling.
Examples of innovation include robotic surgery, chorionic villous sampling, vaginal birth after cesarean section, and continuous birth control pills to treat endometriosis.