amniotic sac


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Related to amniotic sac: placenta, amniotic fluid, yolk sac

sac

 [sak]
a baglike organ or structure; see also bag, pocket, and pouch.
air s's (alveolar s's) the spaces into which the alveolar ducts open distally, and with which the alveoli communicate; see also lung.
amniotic sac the sac formed by the amnion, enclosing the fetus suspended in amniotic fluid; popularly known as the bag of waters.
conjunctival sac the potential space, lined by conjunctiva, between the eyelids and the eyeball.
endolymphatic sac the blind, flattened cerebral end of the endolymphatic duct.
hernial sac the peritoneal pouch that encloses protruding intestine.
lacrimal sac the dilated upper end of the nasolacrimal duct; see also lacrimal apparatus.
yolk sac the extraembryonic membrane connected with the midgut; in vertebrates below true mammals, it contains a yolk mass.
Yolk sac in a developing embryo. From Applegate, 2000.

amniotic sac

An amniotic fluid-filled, thin membranous sac, which surrounds the embryo of amniote vertebrates; it provides a fluid cushion, prevents dehydration and acts as a waste receptacle during embryonic development.

amniotic sac

amnion, bag of waters, membranes Obstetrics An amniotic fluid-filled thin membraned sac which surrounds the embryo of amniote vertebrates, and provides a fluid cushion, prevents dehydration, acting as a waste receptacle during embryonic development. See Amnion.

Amniotic sac

The membranous sac that surrounds the embryo and fills with watery fluid as pregnancy advances.
Mentioned in: Childbirth

Patient discussion about amniotic sac

Q. what does it mean when an ultrasound shows an empty amniotic sac and no baby?

A. This exact thing happened with my friend who is now 22 weeks with her first baby. She had 2 additional sacs - both empty - and the doctor said that the pregnancy had probably started out as triplets but that only one of the embryos had actually established and continued to grow.

Her doctor said it is very common for a woman to have more than one egg fertilize but that in most cases the pregnancy continues as a singleton only. She told my friend that the empty sacs would just disappear through time (which they did) and that they posed no danger to her baby.

More discussions about amniotic sac
References in periodicals archive ?
* A few signs of trouble include seeing feet up to the knee with no head, or hind feet presented first, and yellow discoloration of the fluid in the amniotic sac.
Still, to reach the fetus, the instruments must penetrate the amniotic sac, which cannot heal or easily be sewn shut because it is so fragile.
The researchers dubbed the new structure a post-implantation amniotic sac embryoid, or PASE.
Amniotic Band Syndrome (ABS), also known as ADAM (acronym for Amniotic Deformity, Adhesions, and Mutilations), is a rare condition consisting of a broad group of congenital malformations caused mainly by the rupture of the amniotic sac, which produces a series of alterations due to the appearance of fibrous mesodermal amniotic tissue bands [1].
This pigment mutilates infection-fighting immune system cells, enabling the bacteria--Group B Streptococcus--to quickly cross the placenta and invade the amniotic sac, a new study in monkeys shows.
"It was heartbreaking really - I was already worried that they were monoamniotic (where twins share an amniotic sac), and conjoined was the worstcase scenario.
A baby was successfully delivered while still inside its fully intact amniotic sac, the fluid-filled sac inside the womb that contains and protects the fetus, in a hospital in Spain last week.
In the days before Georgianna was born, medical staff spotted debris in the baby's amniotic sac. The girls were fraternal, so each had her own amniotic sac.
They discovered that baby Jessica had been born still inside her amniotic sac - a rare situation occurring in only one in 80,000 births.
Type I is caused by implantation of the amniotic sac on the scar with progression toward either the cervico-isthmic space or the uterine cavity.
It meant a difficult monochorionic monoamniotic (MoMo) pregnancy for mum Danielle, 28, from Stockton, who had to be monitored three times a day every day due to them sharing the same amniotic sac -although they did not realise they were mirrorimage until after the birth.
I always clean off the nose if the head is out and the amniotic sac is broken, so the kid doesn't aspirate fluid.