Fetus


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fetus

 [fe´tus] (L.)
the developing young in the uterus, specifically the unborn offspring in the postembryonic period, which in humans is from the third month after fertilization until birth. See also embryo. 

The stages of growth of the fetus are fairly well defined. At the end of the first month it has grown beyond microscopic size. After 2 months it is a little over 2.5 cm long, its face is formed, and its limbs are partly formed. By the end of the third month it is 8 cm long and weighs about 30 g; its limbs, fingers, toes, and ears are fully formed, and its sex can be distinguished.

After 4 months the fetus is about 20 cm long and weighs over 200 g. The mother can feel its movements, and usually the health care provider can hear its heartbeat. The eyebrows and eyelashes are formed, and the skin is pink and covered with fine hair called lanugo. By the fifth month the fetus's body is covered with a cheeselike substance (vernix caseosa), which serves to protect it in its watery environment. By the end of the fifth month it is 30 cm long, weighs 450 g, and has hair on its head. At the end of the sixth month it is 35 cm long and weighs 900 g, and its skin is very wrinkled.

After 7 months the fetus is 40 cm long and weighs over 1.3 kg, with more fat under its skin. In the male, the testes have descended into the scrotum. By the end of the eighth month it is 45 cm long, may weigh 2.3 kg, and has a good chance of survival if it is born at that time. At the end of 9 months, the average length of a fetus is 50 cm and the average weight is 3.2 kg. adj., adj fe´tal.
calcified fetus a dead fetus that has become calcified in utero; called also lithopedion.
fetus in fe´tu a small, imperfect fetus, incapable of independent life, contained within the body of another fetus.
harlequin fetus an infant with a severe and dramatic form of congenital ichthyosis, manifested by hyperkeratosis with rigid skin; death usually occurs in the first six weeks of life.
mummified fetus a dead fetus that is dried up and shriveled.
fetus papyra´ceus a dead fetus flattened by being pressed against the uterine wall by a living twin.
parasitic fetus in unequal twins, an incomplete minor fetus attached to a larger, more completely developed fetus (the autosite).

fe·tus

, pl.

fe·tus·es

(fē'tŭs, fē'tŭs-ez), Avoid the incorrect plural feti.
1. The unborn young of a viviparous animal following the embryonic period.
2. In humans, the product of conception from the end of the eighth week of gestation to the moment of birth.
[L. offspring]

fetus

(fē′təs)
n. pl. fe·tuses
1. The unborn young of a viviparous vertebrate having a basic structural resemblance to the adult animal.
2. In humans, the unborn young from the end of the eighth week after conception to the moment of birth, as distinguished from the earlier embryo.

fetus

Obstetris
1. The unborn child developing in the uterus–after the embryonic stage, circa age 7 to 8 wks to birth.
2. The product of conception from the time of implantation until delivery; if the delivered or expelled fetus is viable, it is designated an infant. See Harlequin fetus, Nonviable fetus. Cf Embryo.

fe·tus

, pl. fetuses (fē'tŭs, -ĕz)
1. The unborn young of a viviparous animal after it has taken form in the uterus.
2. In humans, the product of conception from the end of the eighth week to the moment of birth.
Synonym(s): foetus.
[L. offspring]

fetus

The developing individual from about the eighth or tenth week of life in the womb until the time of birth. The fetus has all the recognizable external characteristics of a human being. At 10 weeks, the fetus measures about 2.5 cm from the crown of the head to the rump. The face is formed but the eyelids are fused together. The brain is in a primitive state, incapable of any meaningful form of consciousness. By 3 months, the fetus is about 5 cm long (crown to rump) and by 4 months it is about 10 cm long. In the 6th month, the fetus is up to 20 cm long and weighs up to 800 g. Survival outside the womb at this stage is unlikely. Most fetuses over 2 000 grams do well if properly managed in an INCUBATOR. From the Latin fetus , an offspring. The common spelling ‘foetus’ is incorrect and is used only by journalists who should know better.

Fetus

The term used to describe a developing human infant from approximately the third month of pregnancy until delivery. The term embryo is used prior to the third month.

fe·tus

, pl. fetuses (fē'tŭs, -ĕz) Avoid the incorrect plural feti.
In humans, product of conception from the end of the eighth week of gestation to the moment of birth.
[L. offspring]

Patient discussion about Fetus

Q. Is chicken pox dangerous to my fetus? I am pregnant and have never had chicken pox before. My daughter is 2 years old and has not had chicken pox before and hasn't been vaccinated against it either. If she does catch chicken pox can this be dangerous to me or the fetus?

A. perhaps it will be then useful if the chicken pox would appear that you have then a separate room if necessary (quarantine).
i advice you also to inform yourself and build your own opinion with this link-page:

before you would like to go on with any vaccination, you should check out this very long list of links:

http://www.aegis.ch/neu/links.html

at the bottom you will also find links in english. vaccinations in general are very disputable/dubious and it is probably time that we learn about it.

Q. Is an X- Ray dangerous to my fetus? I fell down while I am pregnant and was sent to the ER. I was given an x- ray there, is the radiation dangerous to my fetus?

A. As far as I know one x-ray cannot harm your fetus since there is not enough radiation there to harm it. If you are worried consult a Doctor.

Q. Can the fetus hear through the womb? My wife wants to play music to our baby and put earphones on her pregnant stomach so he can hear it. Can he really hear the music?

A. Yes, he can hear. Studies show that from the 5th month of pregnancy, nice and calm music can sooth the fetus. You can expose your baby to sounds, music and different tunes throughout your pregnancy.

More discussions about Fetus
References in periodicals archive ?
Teratogenesis may be viewed as differential growth disturbances of some tissues, resulting in the failure of the fetus to maintain its normal expected growth potential for any of the gestational periods (United Nations, 1977).
fetus is primarily associated with extraintestinal, systemic illness which may relapse or persist for years [1,12].
"The fetus, in many cases, dies just as a human adult or child would: It bleeds to death as it is torn apart limb by limb.
This practice decreases the risk of the sensitization of Rh negative mothers to produce anti-D when pregnant with an Rh positive fetus from 16% to only 0.14%.
But Amerini holds that the embryo is, right front its conception, "in the process of becoming a human being." That is, according to his interpretation of Aquinas, the fetus is not yet a human person, but it is in the process of becoming one.
It was concluded that in both superfoetation cases, female fetus was premature and underdeveloped whereas males were live and fully mature.
She had a sonograph at 22 weeks of gestation showing twin gestation with one viable fetus BPD-53 mm, FL-37 mm, maturity of 22 weeks, and a non-viable fetus with absent cardiac activity with an FL-24 mm, maturity of 16 weeks; single placenta anterior in upper uterine segment; and no gross malformations in the viable fetus.
A concerned citizen alerted the barangay watchmen in the area about the fetus.
fetus with markers of reptile origin was reported in 2004 (9).
According to a senior officer, it took the police around two hours to lift the corpse of the seven-month-old fetus from the woman's residence in the Free Zone.
Scientists have captured the images of the fetus in motion by 4D ultrasound.
ISLAMABAD -- In a rare case of medical history, a four month old fetus was found inside body of a two month girls.