Stretch marks, also known as striae () or striae distensae,
are a form of
scar
A scar (or scar tissue) is an area of fibrous tissue that replaces normal skin after an injury. Scars result from the biological process of wound repair in the skin, as well as in other organs, and tissues of the body. Thus, scarring is a na ...
ring on the
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...
with an off-color hue. Over time they may diminish, but will not disappear completely. Striae are caused by tearing of the
dermis
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided i ...
during periods of rapid growth of the body, such as during
puberty
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a girl, the testes in a boy. ...
or
pregnancy
Pregnancy is the time during which one or more offspring develops ( gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins.
Pregnancy usually occurs by sexual intercourse, but ca ...
, in which they usually form during the
last trimester. Usually on the stomach, these striae also commonly occur on the breasts, thighs, hips, lower back, and buttocks. Pregnancy-related striae are known as ''striae gravidarum''. Striae may also be influenced by the
hormonal changes associated with puberty, pregnancy,
bodybuilding
Bodybuilding is the use of progressive resistance exercise to control and develop one's muscles (muscle building) by muscle hypertrophy for aesthetic purposes. It is distinct from similar activities such as powerlifting because it focuses ...
, or
hormone replacement therapy.
There is no evidence that creams used during pregnancy prevent stretch marks.
Once they have formed there is no clearly effective treatment, though various methods have been attempted and studied.
[
]
Signs and symptoms
Striae, or "stretch marks", begin as reddish or purple lesions
A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals.
Types
There is no designated classifi ...
, which can appear anywhere on the body, but are most likely to appear in places where larger amounts of fat are stored; the most common places are the abdomen
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...
(especially near the navel
The navel (clinically known as the umbilicus, commonly known as the belly button or tummy button) is a protruding, flat, or hollowed area on the abdomen at the attachment site of the umbilical cord. All placental mammals have a navel, although ...
), breasts, upper arms, underarms, back, thighs (both inner and outer), hips, and buttocks. Over time, they tend to atrophy
Atrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include mutations (which can destroy the gene to build up the organ), poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply t ...
and lose pigmentation. The affected areas appear empty, and are soft to the touch.
Stretch marks occur in the dermis
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided i ...
, the resilient middle tissue layer that helps the skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...
retain its shape. No stretch marks will form as long as there is support within the dermis; stretching plays a role in where the marks occur and in what direction they run, however, there are a number of contributing factors (see: "Causes", below) to their formation.
They can (but do not always) cause a burning and itching sensation, as well as emotional distress. They pose no health risk in and of themselves, and do not compromise the body's ability to function normally and repair itself, however, they are often considered a cosmetic nuisance. Young women are generally affected the most and often seek treatment for them from a dermatologist and following pregnancy
Pregnancy is the time during which one or more offspring develops ( gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins.
Pregnancy usually occurs by sexual intercourse, but ca ...
.
File:Squircle belly (19004951).jpg, Striae gravidarum in a pregnant woman at 38 weeks
File:Female Torso with Tiger Stripes (Stretch Marks) from Pregnancy.JPG, Stretch marks from pregnancy >1 year postpartum
File:StretchMark.jpg, Normal stretch marks in a teenage male
File:Stretch marks on female breast.jpg, Stretch marks in a female breast
File:Central Obesity 008.jpg, Striae distensae on an obese male
Causes
Stretch marks appear to be caused by stretching of the skin. This is especially true when there is an increase in cortisone an increase in cortisone levels can increase the probability or severity of stretch marks by reducing the skin's pliability. More specifically, it affects the dermis
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided i ...
by preventing the fibroblast
A fibroblast is a type of cell (biology), biological cell that synthesizes the extracellular matrix and collagen, produces the structural framework (Stroma (tissue), stroma) for animal Tissue (biology), tissues, and plays a critical role in wound ...
s from forming collagen
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole ...
and elastin
Elastin is a protein that in humans is encoded by the ''ELN'' gene. Elastin is a key component of the extracellular matrix in gnathostomes (jawed vertebrates). It is highly elastic and present in connective tissue allowing many tissues in the bod ...
fibers necessary to keep rapidly growing skin taut; this can create a lack of supportive material as the skin is stretched, and lead to dermal and epidermal
The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water relea ...
tearing, which in turn can produce scarring in the form of stretch marks. This is particularly the case when there is new tissue growth (which can interfere with the underlying physical support of the dermis or epidermis, by displacing the supportive tissue).
Examples of cases where stretch marks are common, also given by the Mayo Clinic, include weight gain (in the form of fat
In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food.
The term often refers spec ...
and/or muscle
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...
), pregnancy
Pregnancy is the time during which one or more offspring develops ( gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins.
Pregnancy usually occurs by sexual intercourse, but ca ...
, and adolescent growth spurts, though it is also noted that some medications, as well as other medical conditions and diseases, may increase the likelihood of stretch marks appearing. In the case of medication, the Clinic points to "corticosteroid
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involv ...
creams, lotions and pills and chronic use of oral or systemic steroid
A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...
s" as a common contributing factor. Medical conditions that can contribute to stretch marks include Ehlers-Danlos syndrome, Cushing's syndrome, Marfan syndrome
Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Those with the condition tend to be tall and thin, with long arms, legs, fingers, and toes. They also typically have exceptionally flexible joints a ...
, and "adrenal gland diseases".
Pregnancy
Pregnancy stretch marks, also known as ''striae gravidarum'', are a specific form of scarring of the skin of the abdominal area due to rapid expansion of the uterus
The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The uter ...
as well as sudden weight gain during pregnancy. About 90% of pregnant women are affected.
A number of additional factors appear to promote the appearance of stretchmarks: one study of 324 women, done just after they had given birth, demonstrated that low maternal age, high body mass index, weight gain over 15 kg (33 pounds) and higher neonatal birth weight were independently correlated with the occurrence of striae. Teenagers were found to be at the highest risk of developing severe striae.
These skin marks are symptoms of pregnancy caused by the tearing of the dermis
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided i ...
, resulting in atrophy
Atrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include mutations (which can destroy the gene to build up the organ), poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply t ...
and loss of rete ridges
Rete pegs (also known as rete processes or rete ridges) are the epithelial extensions that project into the underlying connective tissue in both skin and mucous membranes.
In the epithelium of the mouth, the attached gingiva exhibit rete pegs, wh ...
. These scars often appear as reddish or bluish streaks on the abdomen, and can also appear on the breasts and thighs. Some of these striae disappear with time, while others remain as permanent discolorations of the body.
Mechanical distension and rapidly developing areas of the body during pregnancy (such as the abdomen, breasts, and thighs) are most commonly associated with striae formation. Some have suggested that relaxin
Relaxin is a protein hormone of about 6000 Da first described in 1926 by Frederick Hisaw.
The relaxin family peptide hormones belong to the insulin superfamily and consists of seven peptides of high structural but low sequence similarity; rela ...
and estrogen
Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal acti ...
combined with higher levels of cortisol
Cortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone.
It is produced in many animals, mainly by the ''zona fasciculata'' of the adrenal cortex in the adrenal gland ...
during pregnancy can cause an accumulation of mucopolysaccharides, which increases water absorption of connective tissue
Connective tissue is one of the four primary types of animal tissue, along with epithelial tissue, muscle tissue, and nervous tissue. It develops from the mesenchyme derived from the mesoderm the middle embryonic germ layer. Connective tiss ...
, making it prime for tearing under mechanical stress. There also seems to be an association between higher body mass indices and in women with bigger babies and the incidence and severity of striae. Also, younger women seem to be at higher risk of developing striae during pregnancy.
The prevalence and severity of striae gravidarum varies among populations. The current literature suggest that in the general population of the US, there is a 50%-90% prevalence of striae associated with pregnancy, partly as a result of the normal hormonal changes of pregnancy and partly due to stretching of skin fibers. Many women experience striae gravidarum during their first pregnancy. Nearly 45% percent of women develop striae gravidarum before 24 weeks of gestation. Many women who develop lesions during the first pregnancy do not develop them during later pregnancies. Genetic factors such as genealogy
Genealogy () is the study of families, family history, and the tracing of their lineages. Genealogists use oral interviews, historical records, genetic analysis, and other records to obtain information about a family and to demonstrate kins ...
and race also seem to be predictive in the appearance of striae.
Prevention
Collagen and elastin are proteins in the skin that contribute to the skin's strength, resilience, flexibility, and help skin that has been stretched to recover its original state. Boosting the production of collagen and elastin helps prevent stretch marks from occurring. Stretch marks can also derive from nutritional deficiencies. Consuming foods that contribute to the skin's health, such as zinc-rich foods, foods high in vitamin A, C, D, and protein rich foods, can help suppress stretch marks. A systematic review has not found evidence that creams and oils are useful for preventing or reducing stretch marks in pregnancy. The safety in pregnancy of one ingredient, '' Centella asiatica'', has been questioned. Evidence on treatments for reducing the appearance of the scars after pregnancy is limited.
Treatment
There are no clearly useful treatments for stretch marks, although there are many different suggestions on how to remove them or lessen their appearance.
Various efforts that have been tried including laser treatments, glycolic acid, and microdermabrasion. Tretinoin
Tretinoin, also known as all-''trans'' retinoic acid (ATRA), is a medication used for the treatment of acne and acute promyelocytic leukemia. For acne, it is applied to the skin as a cream, gel or ointment. For leukemia, it is taken by mouth f ...
(0.1% w/w), which is a retinoid
The retinoids are a class of chemical compounds that are vitamers of vitamin A or are chemically related to it. Retinoids have found use in medicine where they regulate epithelial cell growth.
Retinoids have many important functions throughout t ...
, has found to be effective on early stretch marks in several studies. Hyaluronic acid also improves the appearance of stretch marks. Topical tretinoin is categorized by the FDA as a known teratogen (causing malformations in fetuses) in animals, without adequate human studies on safety in pregnancy.
Carboxytherapy
Carboxytherapy is a non-surgical cosmetic medicine treatment for dermatology. Carboxytherapy employs injections or transdermal application to infuse gaseous carbon dioxide below the skin into the subcutaneous tissue through a needle or skin. It has ...
is a known procedure; however, there is a lack of evidence to support how effective it is.
History
Since ancient times, pregnant women have sought remedies to prevent stretch marks during pregnancy. Both ancient Greeks
The Greeks or Hellenes (; el, Έλληνες, ''Éllines'' ) are an ethnic group and nation indigenous to the Eastern Mediterranean and the Black Sea regions, namely Greece, Cyprus, Albania, Italy, Turkey, Egypt, and, to a lesser extent, oth ...
and Romans used olive oil
Olive oil is a liquid fat obtained from olives (the fruit of ''Olea europaea''; family Oleaceae), a traditional tree crop of the Mediterranean Basin, produced by pressing whole olives and extracting the oil. It is commonly used in cooking: f ...
, while Ethiopians
Ethiopians are the native inhabitants of Ethiopia, as well as the global diaspora of Ethiopia. Ethiopians constitute several component ethnic groups, many of which are closely related to ethnic groups in neighboring Eritrea and other parts of ...
and Somalis
The Somalis ( so, Soomaalida 𐒈𐒝𐒑𐒛𐒐𐒘𐒆𐒖, ar, صوماليون) are an ethnic group native to the Horn of Africa who share a common ancestry, culture and history. The Lowland East Cushitic Somali language is the shared ...
used frankincense
Frankincense (also known as olibanum) is an aromatic resin used in incense and perfumes, obtained from trees of the genus ''Boswellia'' in the family Burseraceae. The word is from Old French ('high-quality incense').
There are several species o ...
.
Striae were first recognized by Roederer in 1773, and were later histologically described by Troisier and Ménétrier in 1889. In 1936, Nardelli made the first morphologically correct descriptions.
Terminology
Medical terminology
Medical terminology is a language used to precisely describe the human body including all its components, processes, conditions affecting it, and procedures performed upon it. Medical terminology is used in the field of medicine
Medical terminolog ...
for these kinds of markings includes striae atrophicae, vergetures, stria distensae, striae cutis distensae, lineae atrophicae, linea albicante, or simply striae.
References
External links
{{DEFAULTSORT:Stretch Marks
Abnormalities of dermal fibrous and elastic tissue
Human pregnancy
Obstetrics
Medical conditions related to obesity
Health issues in pregnancy
Pregnancy-related cutaneous conditions
Pathology of pregnancy, childbirth and the puerperium