While all babies have lanugo in the womb, not all babies are born with anything up top -- and mothers looking to know ahead of time whether their kid will be fuzzy-headed or bald may be able to use their own heartburn as a clue.
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Heartburn is a harbinger of a hairy baby Here's a horrifying fact about babies: Sometime in the second trimester of pregnancy, they develop a coat of fine hair all over their bodies, called lanugo -- and sometime in the third trimester, they shed it and eat it.
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Without the lanugo to anchor the vernix caseosa, these functions would be compromised.
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During human development, the lanugo grows on fetuses as a normal part of gestation, but it is usually shed and replaced by vellus hair at about thirty-three to thirty-six weeks of gestational age. As the lanugo is shed from the skin, it is normal for the hair to be consumed by the developing fetus, since it drinks from the amniotic fluid and urinates into its environment. As a result, lanugo contributes to the new-born baby's meconium. The presence of lanugo on new- borns is not necessarily a sign of premature birth, as it also seen on infants born at thirty-nine weeks of gestation (full term).
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Some authors have claimed that fetal whales also have lanugo. However, there is no supporting evidence for such claims.
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Some newborns have a fine, downy body hair called lanugo. It may be particularly noticeable on the back, shoulders, forehead, ears and face of premature infants. Lanugo disappears within a few weeks. Infants may be born with full heads of hair; others, particularly caucasian infants, may have very fine hair or may even be bald.
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Lanugo is also common on other animals. For example, seals and elephantsEcology of the Asian Elephant in Lowland Dry Zone Habitats of the Mahaweli River Basin, Sri Lanka Natarajan Ishwaran Journal of Tropical Ecology, Vol. 9, No. 2 (May, 1993), pp. 169-182The Hair, Paul MacKenzie, Elephant Information Repository websiteElephant Hair, Elephant Anatomy, Animal Corner website are often born with a covering of lanugo.
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Vellus hair is most easily observed on children and adult women, who generally have less terminal hair to obscure it. Vellus hair is not lanugo hair. Lanugo hair is a much thicker type of hair that normally grows only on fetuses. Vellus hair is differentiated from the more visible terminal or androgenic hair, which develops only during and after puberty, usually to a greater extent on men than it does on women.
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Bones are fully developed, but are still soft and pliable. Iron, calcium, and phosphorus become more abundant. Fingernails reach the end of the fingertips. The lanugo, or fine hair, begins to disappear, until it is gone except on the upper arms and shoulders.
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The hands were placed on the front of the thighs. The mummy lacked eyebrows and eyelashes, presumably due to its early gestational age, but light-coloured silky hairs (lanugo) were present on the head. The eyelids were slightly open. The remains of the umbilical cord was preserved to a length of .
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Lanugo functions as an anchor to hold the vernix caseosa on the skin. Together they protect the delicate fetal skin from being damaged by the amniotic fluid. The vernix caseosa also helps to prepare the fetus for life outside the womb. It provides lubrication for birth and contributes to thermoregulation, prevention of water loss, and innate immunity.
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They will also eat the ringed seal remains leftover from the polar bear kills. Greenland sharks and the occasional Atlantic walrus also may prey on ringed seals in the water. Pups have several behaviors that are adaptive responses to predation pressure. These include their time spent practicing diving, use of breathing holes, prolonged lanugo stage, and ability to hide in snow caves.
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Two young individuals in New York Aquarium, 1910 Caribbean monk seals had a long pupping season, which is typical for pinnipeds living in subtropical and tropical habitats. In Mexico, breeding season peaked in early December. Like other monk seals, this species had four retractable nipples for suckling their young. Newborn pups were probably about in length and weighed and reportedly had a sleek, black lanugo coat when born.
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During a lull in the warfare, Gustavus Adolphus hurried back to Stockholm to await the arrival of the baby. The birth was a difficult one. On 7 December, a baby was born with a fleece (lanugo), which enveloped it from its head to its knees, leaving only its face, arms and lower part of its legs free. Moreover, it had a large nose and was covered with hair.
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Meconium is the earliest stool of a mammalian infant. Unlike later feces, meconium is composed of materials ingested during the time the infant spends in the uterus: intestinal epithelial cells, lanugo, mucus, amniotic fluid, bile and water. Meconium, unlike later feces, is viscous and sticky like tar, its color usually being a very dark olive green; it is almost odorless.Persis Mary Hamilton, Basic Pediatric Nursing (Maryland Heights MO: Mosby, 1991), 82.
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It progresses through three stages: #Lochia rubra (or cruenta) is the first discharge, Composed of blood, shreds of fetal membranes, decidua, vernix caseosa, lanugo and membranes. It is red in color because of the large amount of blood it contains. It lasts 1 to 4 days after birth, before easing to light "spotting". #Lochia serosa is the term for lochia that has thinned and turned brownish or pink in color.
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Male and female South American sea lions, showing sexual dimorphism Almost all pinnipeds have fur coats, the exception being the walrus, which is only sparsely covered. Even some fully furred species (particularly sea lions) are less haired than most land mammals. In species that live on ice, young pups have thicker coats than adults. The individual hairs on the coat, known collectively as lanugo, can trap heat from sunlight and keep the pup warm.
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Vellus hair replaces lanugo hair on a human fetus at 36 to 40 weeks of gestation. The growth cycle of vellus hair is different from the growth cycle of terminal hair. At puberty, androgen hormones cause much of the vellus hair to turn into terminal hair and stimulate the growth of new hair in the armpit and the pubic area. In men, this change in vellus hair occurs on the face and the body.
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Lanugo is very thin, soft, usually unpigmented, downy hair that is sometimes found on the body of a fetal or new-born human. It is the first hair to be produced by the fetal hair follicles, and it usually appears around sixteen weeks of gestation and is abundant by week twenty. It is normally shed before birth, around seven or eight months of gestation, but is sometimes present at birth. It disappears on its own within a few weeks.
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Pups are born with a light brown, downy pelage (lanugo), until the first molt at weaning. Younger animals are marked by net- like, chocolate brown markings and flecks on the shoulders, sides and flanks, shading into the predominantly dark hind and fore flippers and head, often due to scarring from leopard seals. After molting, their fur is a darker brown fading to blonde on their bellies. The fur lightens throughout the year, becoming completely blonde in summer.
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At birth they pups are approximately 60-65 cm in length and weigh 4.5-5.0 kg. The pups are born with a white natal coat of blubber, known as the “lanugo,” that provides insulation until it sheds after 4-6 weeks. The pups nurse for as long as 2 months in stable shorefast ice, but for as little as 3-6 weeks in moving ice. During nursing, Arctic ringed seals spend about 50% of their time in the water, and practice developing deep diving skills.
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Adult males usually bear scars, most of them around the genital region. Weddell seal pups are born with a lanugo of similar coloration and they moult after 3–4 weeks; later, they turn a darker color similar to that of adults. The pups are around half the length of their mother at birth, and weigh 25–30 kg (55–66 lb). They gain around 2 kg (4.4 lb) a day, and by 6–7 weeks old they can weigh around 100 kg (220 lb).
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One male will occupy an area throughout the breeding season, and they will return to the same display area in consecutive years. Female harbour seals receive direct benefits from being in a lek, as the congregation of males into an area makes mate selection easier because females do not have to travel as far and it also helps to reduce exposure to predators. Spotted seal triad during the breeding season: lanugo-clad pup (left), mother (center), and attending male (right in water). Harbour seal males use underwater vocalizations and display dives within their aquatic territories, for both female attraction and male-male competition.
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The word meconium is derived from the Greek word mēkōnion meaning juice from the opium poppy as the sedative effects it had on the foetus were observed by Aristotle. Meconium is a sticky dark- green substance which contains gastrointestinal secretions, amniotic fluid, bile acids, bile, blood, mucus, cholesterol, pancreatic secretions, lanugo, vernix caseosa and cellular debris. Meconium accumulates in the foetal gastrointestinal tract throughout the third trimester of pregnancy and it is the first intestinal discharge released within the first 48 hours after birth. Notably, since meconium and the whole content of the gastrointestinal tract is located ‘extracorporeally,’ its constituents are hidden and normally not recognised by the foetal immune system.
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It tends to be more common in the restricting subtype of this disease, and is associated with numerous other dermatologic manifestations, such as brittle hair and nails, lanugo-like body hair, and xerosis. Although Alzheimer's disease has been associated with carotenoderma in some reports, most studies on serum carotenoids in these patients show that their levels of carotenoids and retinol are depressed, and may be associated with the development of dementia. A true association between Alzheimer's disease and carotenoderma is unclear at this time. There have been case reports in the literature of increased serum carotenoids and carotenoderma that is unresponsive to dietary measures, with a genetic defect in carotenoid metabolic enzymes proposed.
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For example, terminal hairs grow on the scalp and lanugo hairs are seen covering the bodies of fetuses in the uterus and in some newborn babies. The process of hair growth occurs in distinct sequential stages. The first stage is called anagen and is the active growth phase, telogen is the resting stage, catagen is the regression of the hair follicle phase, exogen is the active shedding of hair phase and lastly kenogen is the phase between the empty hair follicle and the growth of new hair. The function of hair in humans has long been a subject of interest and continues to be an important topic in society, developmental biology and medicine.
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