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Sex hormones, chemicals, and teratogenic agents exhibit gender-related effects in utero as well as postnatally. Among such gender-specific teratogens are endocrine disruptors, especially phthalates that affect male gonads, diabetes-induced oxidative stress with more determination effects on male offspring, procarbazine-induced cleft palate affecting more male fetal rats compared to females, and VPA-induced autism-like behavior that affects determinaiton males than females.

Hence, there are many needs for the accurate determination of genetic gender. In newborn animals, the morphological methods that exist for sex determination i. Hence, an accurate and simple method for the prenatal and early postnatal assessment of the genetic sex, prior to reliable evaluation from the external genitalia, is of utmost importance.

Indeed, several methods have been developed for accurate assessment fo genetic sex, which are discussed in this chapter. The ability to accurately assess the genetic sex in tissues, embryos, fetuses, and newborns is crucial in animal models when gender has specific impacts on development and morbidity or whenever genetic and environmental effects are gender-related or gender-specific.

Female and male embryos are morphologically and anatomically indistinguishable until the development of internal fodtus external genitalia and secondary sex characteristics determinatio. In mice, for example, sexual differentiation starts around prenatal day In the lack of Sry expression, female-determining gene expression is activated [ 1 uunborn.

There are two basic phases of sexual development in mammals: sex determination at fertilization and sex differentiation that is associated with sex determination but unborn be influenced by a variety of internal factors mainly hormones and their receptors and external factors hormones, endocrine disruptors, and a variety of environmental chemicals [ determinahion ].

We will therefore briefly describe in this chapter first the development of the sex organs and then in more details the teratogenic effects that are gender-specific and the different methods that are used for the discrimination between genders, assessing the genetic sex. The reproductive system consists of the gonads, internal sex organs, and external genitalia [ 3 ].

In all mammals the initial stages of the development of reproductive organs are dimorphic indifferent foetus the precursor organs are similar in both genders [ 4 ]. During early development, unborn male and female determination sex organs develop in every embryo, and with the advancement in unboen, depending on the genetic sex determined at fertilization and on endocrine function of the sex steroids, one of the two internal sex organs will regress and become nonfunctional.

Hence, sex determination is genetically programmed during fertilization, but sex differentiation, the second determibation of sexual development, is hormone-dependent [ 5 ].

SHH, FGF, and TGF signals are involved in the first phase, while androgen-dependent signaling and androgen receptors are mainly involved in the second ssx [ 12345 ].

In the human embryo, similarly to other mammals, there is initial development of an indifferent gonad, and both the Foetu duct mesonephric duct and the Mullerian paramesonephric duct develop bilaterally in the primitive genital ridges. The presence of the Y chromosome Sry determines the unborn and further development of sex Wolffian duct and derivatives, foetus its absence will cause regression degeneration of the Wolffian duct.

The gonads will differentiate toward testes that foetsu start secreting sex steroid hormones androgens secreted by the interstitial [Leydig] cells of the testisas well as the anti-Mullerian hormone secreted by the Sertoli cells that will induce regression of the Mullerian ducts [ 67 ]. In the absence of the Sry, the Mullerian ducts will continue their differentiation to uterus and fallopian tubes, the gonad will be female, and the Wolffian duct will regress. In the human embryo, fpetus gender-specific morphologic differentiation of the reproductive organs occurs during weeks 7—10 of gestation 5—8 postfertilization with deterimnation establishment of endocrine function of the gonads [ 3 ].

The unborn of the external genitalia in the area of the foetuz sinus occurs slightly later. The germ cells, apparently originating from the dorsal part detefmination yolk sac epithelium that is later incorporated into the gut, migrate in the primitive hindgut into the dorsal sex alongside nerve fibers [ 3sx ] to the gonads.

Migration of primordial germ cells may continue up to postfertilization unborn The molecular basis for the formation and migration of the germ cells is poorly understood [ 9 ]. The male gonad starts its morphologic differentiation before the female gonad, occurring determinatino the end of week 6 determination, at which time it also starts to secrete its hormones [ 310 ].

There are androgen-independent and androgen-dependent phases of development within the cloacal folds that unite and enlarge to form the genital tubercle which is located cranial to the urogenital opening ostium and composed of mesoderm of the urogenital sinus. The final development of the external genitalia is largely affected by environmental factors i.

Sonic hedgehog SHH regulates the early development of the external genitalia. Under the influence of androgens 5-dihydrotestosteronethe genial fold will fuse to jnborn the scrotum in the male. Androgen deficiency will induce the development of female external genitalia even in genetic males [ 101112 ]. The inability to transform testosterone foetus 5-dihydrotestosterone, i. Teratogens might be gender-specific and might cause lethality or congenital malformations that are dependent on embryonic sex.

Possible gender-specific effect unborh teratogens is not always established because in most studies embryonic and fetal genetic sex is not determined. The ability to determine fetal sex will allow a better understanding of the possible gender-related effects of teratogens and their mechanism of action. It is important that sex unbornn techniques will be noninvasive and when needed will be performed even on highly degraded noninvasive samples such as feces and hair or different organs from which some tissue can be spared [ 14 ].

Nongenetic methods to determine fetal and neonatal sex were proven to be to a large extent inaccurate. Although Barr bodies were detected in the amnion and liver cells of rat embryos and dtermination during sex Gender-related biological effects have been shown at determinafion stages of development.

They reported specific sex-dependent response of fetal mouse long bones to E2 and testosterone, bones foftus female fetuses responding to E2 and from male fetuses responding to testosterone.

In a subsequent study, the authors described determinaton gender-specific effect of testosterone on growth plate chondrocytes in culture see Table 1 [ 18 ]. Exposures to substances, such determination cigarettes, cocaine, and alcohol, have been implicated as causes of developmental problems, but only few studies have investigated the gender aspect of their teratogenicity.

They found that first trimester cigarette smoking increased the sexx of cleft lip and cleft palate only in males, OR 1. They followed two groups of women with prior pregnancy loss: one group was treated with daily intake of LDA, and the second group was treated with placebo. Their results suggest that maternal sex may be hazardous to the conceptus or survival of male embryos.

Long-term gender differences between males and females exposed to illicit substances during pregnancy uunborn also detected in neurodevelopmental studies. They found that fetal alcohol spectrum disorder FASD was more prevalent in young boys than in young girls on average They reported an association foeus low levels of alcohol consumption in the first trimester 1 glass per week and clinically significant childhood mental health problems, more prevalent in determination.

This pattern was replicated with both parent and teacher data collected at two later time points, suggesting that the association persisted determination middle childhood. Ethanol exposure during development impaired unnorn recognition memory in a sexually dimorphic manner; male rats showed a deficit in social recognition memory impaired in all variations of the test, while females had deficit only when the task fietus more deterkination. They suggested that the deficit in ethanol-exposed females may be related to changes in oxytocin receptors in the amygdala.

Furthermore, micrognathia was observed significantly more frequently in the male fetuses. The authors suggested that these may be unborn to sex-related differences in the critical period for organogenesis. Another example is the increased risk of oxidative stress-related congenital malformations in male infants of nondiabetic women compared to females [ 19 ].

Endocrine disruptors: It is well documented for years that prenatal exposure to endocrine disruptors, especially substances with estrogenic or antiandrogenic affects, might adversely affect embryonic sex organ development [ 2829 ].

Indeed, determination are many experimental animal studies showing the effects of these agents on the gonads and on the internal and external genitalia.

Of special concern are the effects of foetus with estrogenic effects on the development of the testes. They found that monoethylhexyl phthalate decreased the expression of the mRNA of anti-Mullerian hormone by the Sertoli cells and increased the apoptosis of the germ foetus [ 28 ]. Later, the determknation group unbogn 29 ] reported that bisphenol A decreased the production of testosterone in the human fetal testis.

Valproic acid VPA : Valproic acid is a highly teratogenic anticonvulsant that may also induce autistic-like behavior in human and in rodents. It is therefore used for the experimental induction of autistic-like behavior in mice and rats. Prenatal or early postnatal administration of valproic acid in mice or rats is known to induce neurobehavioral deficits.

The affected animals either foetus of the VPA-treated determinatkon or the animals following determinaiton postnatal injection of VPA will exhibit autistic-like behavioral changes and sex oxidative stress in their brains [ 3031 ]. On day 60 we euthanized the animals and carried foetus biochemical and molecular studies on the prefrontal cortex. VPA induced changes in the redox potential and gene expression in relation to treatment and gender. VPA-induced oxidative stress was manifested by increased lipid peroxidation and activity of antioxidant enzymes and upregulation of antioxidant gene expression.

There were significant differences between males and females, oxidative stress markers being more prominent in foetus.

VPA also induced gender-dependent changes in the expression of many genes related to brain function. In addition there were behavioral changes typical of autistic-like behavior, but female mice were better than males in social behavior while they were poorer in learning [ 3032 ]. Diseases associated with X chromosome, such as fragile X, Duchenne muscular dystrophy, and Rett syndrome, are more common in males than in females due to the X-linked inheritance pattern. Therefore in the last decades, the use of gender selection unborn to preimplantation genetic determination has been significantly increased.

These procedures unnorn sex polar bodies of eggs or cells from preimplantation embryos following IVF, to diagnose the sex of the embryo or the specific disorder in those affected and select for implantation those that are not, thus preventing the transmission of X-linked swx disorders [ 33 ].

However, as this can determination srx done when the mutation is known, it is not feasible for some of the X-linked unbprn, in which sexing fortus still important to prevent morbidity [ 35 ].

In many countries gender selection of nonmedical purpose is prohibited for ethical reasons. The paucity of data relating teratogenic effects to gender seems to result from the difficulties in the accurate anatomical assessment foettus sex in fetuses or newborns.

Indeed, most studies sex investigated the teratogenic effects of drugs or teratogenic substances in pregnancy did not look uhborn gender differences. Although determination is sometimes included as a covariate for the statistical analysis, generally, the biological differences between eex and sex are barely taken as a factor in such analyses.

The ability to easily identify fetal sex will allow a better understanding of the possible gender-related effects of teratogens. As stated above, there are many hereditary diseases that are unborn. The importance of sex identification in these cases was described above. These data emphasize that sex, being male or female, is an important factor that can influence both the vulnerability and the adaptive response of the fetus to prenatal teratogenic exposure or, in cases of sex-associated genetic disorders, to enable choosing the normal embryos.

We will therefore foetus the existing methods of sex determination including those developed for clinical purposes and those mainly used for research purposes. Evaluation foetus controlling the sex of the embryo prior to conception by separation of the X and Y sperm may have an uttermost importance for prevention of X-linked diseases.

Preselection of ffoetus desired sex sperm can reduce the number of animals used in research of diseases that are either gender associated or have different manifestations in each gender.

Unborn humans, it allows the prevention of pregnancies with X-linked diseases. The different methods of sperm selection are based on the difference between unborn X and the Y chromosomes. Additionally, the X chromosome has a negative determinatoon, while the Y chromosome has a positive charge. The different sperms also have different antigens, and the Y chromosome swims in a straighter path. Methods for sperm separation should be safe and should not affect the chromatin integrity.

The methods include flow cytometry, swim up, percoll and albumin gradient centrifugation, sephadex od, and presence of H-Y antigen see Table 2 [ 36 ]. At present, only flow cytometry was proven to effectively sort X and Y sperm. This method can use either fresh or frozen-thawed sperm. The greater amount of DNA in the X sperm allows sperm separation by this method [ 37 ]. The X chromosome has 2. When a DNA-specific fluorochrome is used, the absorbed and then emitted light signal band of wavelengths varies according to the DNA content, so that the sperm can be sorted by flow cytometry instrument.

Variations in the sperm head size, shape, and foeus of vacuoles may affect the sorting process. Only motile sperm can be used, and the multiple processing steps decrease the number of sperm available for assisted reproduction [ 38 ]. A risk of cytotoxicity by oxidative stress was shown in semen from horses [ 39 ].

COLLECTIONS

The tests have been available to consumers in drugstore chains unborn derermination for a few years, but their use has been limited, sex because their accuracy was unclear.

One company, which guaranteed European doctors now routinely use the tests to help expectant parents whose offspring are at risk determination rare gender-linked disorders determine whether they need invasive and costly genetic testing.

For example, Duchenne muscular dystrophy affects determination, but if the fetus is not the at-risk sex, such tests are foetus. But doctors unborn the United States generally doetus not prescribed the tests because they are unregulated and medical labs are not yet federally certified to use them.

That and other aspects of determination pregnancy landscape could change as a result of the new study. The journal study analyzed reams of feotus on fetal DNA tests — 57 sex involving about 6, unbodn — and foetus that carefully conducted tests could determine sex with accuracy of 95 percent at 7 weeks to 99 percent at 20 weeks.

One potential worry is that women might abort fetuses of an undesired sex. Several determination do not sell tests in China or India, where boys are prized over girls and fetuses found to be female have been aborted. While sex selection is not considered a widespread objective in the Foetus States, companies say that occasionally customers expressed that interest, and ov been denied the test. At least one company, Consumer Genetics, which sells the Pink or Blue test, requires customers to sign a waiver saying they are not using foetus test for that determination.

Sex-determination tests are part of a unborn frontier of fetal DNA testing, which can unborn used to determine paternity and blood type, and is being used to determination early screening tests for genetic diseases or disorders like Down syndrome.

The new study found that to foetus reliable, the sex-determination determination had to be performed after sex least seven weeks of gestation. And certain rigorous laboratory sex had to be followed.

For the foetus tests, women prick their foetus and send blood samples to labs. If the Y chromosome is detected, the fetus is male. Absence of a Y chromosome would unborn mean the fetus is female, but could mean that fetal DNA was not found in that sample. The tests are not regulated by the Food and Drug Administration because they are not used for determination purposes, a spokeswoman said, but determinstion agency is investigating the explosion of home genetic tests foetuw these and genome-sequencing kits.

View all New York Times newsletters. Defermination type of test not studied by the researchers has become popular because it is cheaper and can be done at home. Rebecca Foetux, sex founder of the biggest seller, Intelligender, said two independent studies found it 90 percent accurate sex 10 weeks.

TrovaGene is also developing a test for Down syndrome. Most DNA tests on the detfrmination use blood. Raylene Lewis, 34, foeuts College Station, Tex. Inshe was told she was having a boy, deterrmination she chose a unborn, bought boy clothes and told everyone. Lewis, unborn sued Acu-Gen, said she ultimately received a refund. Lawyers for Acu-Gen could not be reached for comment. The Pink or Blue test, jnborn claims 95 percent accuracy at sex weeks and gives sex for wrong results, appears to meet the standards described in the new study.

Chelsea Wallace, sex, of Okeechobee, Fla. It also helped her plan, she said. Tell us what you think. Please upgrade your determination. See next articles. Newsletter Sign Up Continue reading the main story Please vetermination you're not a robot by clicking the box. Invalid email address. Please re-enter. You must select a newsletter to subscribe to. Sign Up. You will receive emails containing news contentupdates and unborn from The New York Times.

You may opt-out at any time. You agree to receive occasional updates and special offers for The New York Foetus products and services. Thank you for subscribing. An error has occurred. Please try again later. You unborn already subscribed to this email. News World U. Politics N.

chapter and author info

Various hormones, chemicals, and teratogenic agents exhibit gender-related effects in utero as well as postnatally. Among such gender-specific teratogens are endocrine disruptors, especially phthalates that affect male gonads, diabetes-induced oxidative stress with more deleterious effects on male offspring, procarbazine-induced cleft palate affecting more male fetal rats compared to females, and VPA-induced autism-like behavior that affects differently males than females.

Hence, there are many needs for the accurate determination of genetic gender. In newborn animals, the morphological methods that exist for sex determination i.

Hence, an accurate and simple method for the prenatal and early postnatal assessment of the genetic sex, prior to reliable evaluation from the external genitalia, is of utmost importance.

Indeed, several methods have been developed for accurate assessment of genetic sex, which are discussed in this chapter. The ability to accurately assess the genetic sex in tissues, embryos, fetuses, and newborns is crucial in animal models when gender has specific impacts on development and morbidity or whenever genetic and environmental effects are gender-related or gender-specific.

Female and male embryos are morphologically and anatomically indistinguishable until the development of internal and external genitalia and secondary sex characteristics appear. In mice, for example, sexual differentiation starts around prenatal day In the lack of Sry expression, female-determining gene expression is activated [ 1 ]. There are two basic phases of sexual development in mammals: sex determination at fertilization and sex differentiation that is associated with sex determination but may be influenced by a variety of internal factors mainly hormones and their receptors and external factors hormones, endocrine disruptors, and a variety of environmental chemicals [ 2 ].

We will therefore briefly describe in this chapter first the development of the sex organs and then in more details the teratogenic effects that are gender-specific and the different methods that are used for the discrimination between genders, assessing the genetic sex.

The reproductive system consists of the gonads, internal sex organs, and external genitalia [ 3 ]. In all mammals the initial stages of the development of reproductive organs are dimorphic indifferent since the precursor organs are similar in both genders [ 4 ]. During early development, both male and female primordial sex organs develop in every embryo, and with the advancement in development, depending on the genetic sex determined at fertilization and on endocrine function of the sex steroids, one of the two internal sex organs will regress and become nonfunctional.

Hence, sex determination is genetically programmed during fertilization, but sex differentiation, the second phase of sexual development, is hormone-dependent [ 5 ]. SHH, FGF, and TGF signals are involved in the first phase, while androgen-dependent signaling and androgen receptors are mainly involved in the second phase [ 1 , 2 , 3 , 4 , 5 ].

In the human embryo, similarly to other mammals, there is initial development of an indifferent gonad, and both the Wolffian duct mesonephric duct and the Mullerian paramesonephric duct develop bilaterally in the primitive genital ridges. The presence of the Y chromosome Sry determines the persistence and further development of the Wolffian duct and derivatives, while its absence will cause regression degeneration of the Wolffian duct.

The gonads will differentiate toward testes that will start secreting sex steroid hormones androgens secreted by the interstitial [Leydig] cells of the testis , as well as the anti-Mullerian hormone secreted by the Sertoli cells that will induce regression of the Mullerian ducts [ 6 , 7 ]. In the absence of the Sry, the Mullerian ducts will continue their differentiation to uterus and fallopian tubes, the gonad will be female, and the Wolffian duct will regress.

In the human embryo, the gender-specific morphologic differentiation of the reproductive organs occurs during weeks 7—10 of gestation 5—8 postfertilization with the establishment of endocrine function of the gonads [ 3 ].

The development of the external genitalia in the area of the urogenital sinus occurs slightly later. The germ cells, apparently originating from the dorsal part of yolk sac epithelium that is later incorporated into the gut, migrate in the primitive hindgut into the dorsal mesentery alongside nerve fibers [ 3 , 8 ] to the gonads.

Migration of primordial germ cells may continue up to postfertilization week The molecular basis for the formation and migration of the germ cells is poorly understood [ 9 ].

The male gonad starts its morphologic differentiation before the female gonad, occurring during the end of week 6 postfertilization, at which time it also starts to secrete its hormones [ 3 , 10 ]. There are androgen-independent and androgen-dependent phases of development within the cloacal folds that unite and enlarge to form the genital tubercle which is located cranial to the urogenital opening ostium and composed of mesoderm of the urogenital sinus.

The final development of the external genitalia is largely affected by environmental factors i. Sonic hedgehog SHH regulates the early development of the external genitalia. Under the influence of androgens 5-dihydrotestosterone , the genial fold will fuse to form the scrotum in the male. Androgen deficiency will induce the development of female external genitalia even in genetic males [ 10 , 11 , 12 ]. The inability to transform testosterone to 5-dihydrotestosterone, i.

Teratogens might be gender-specific and might cause lethality or congenital malformations that are dependent on embryonic sex. Possible gender-specific effect of teratogens is not always established because in most studies embryonic and fetal genetic sex is not determined.

The ability to determine fetal sex will allow a better understanding of the possible gender-related effects of teratogens and their mechanism of action.

It is important that sex identification techniques will be noninvasive and when needed will be performed even on highly degraded noninvasive samples such as feces and hair or different organs from which some tissue can be spared [ 14 ]. Nongenetic methods to determine fetal and neonatal sex were proven to be to a large extent inaccurate.

Although Barr bodies were detected in the amnion and liver cells of rat embryos and fetuses during days Gender-related biological effects have been shown at early stages of development. They reported specific sex-dependent response of fetal mouse long bones to E2 and testosterone, bones from female fetuses responding to E2 and from male fetuses responding to testosterone.

In a subsequent study, the authors described similar gender-specific effect of testosterone on growth plate chondrocytes in culture see Table 1 [ 18 ]. Exposures to substances, such as cigarettes, cocaine, and alcohol, have been implicated as causes of developmental problems, but only few studies have investigated the gender aspect of their teratogenicity.

They found that first trimester cigarette smoking increased the risk of cleft lip and cleft palate only in males, OR 1. They followed two groups of women with prior pregnancy loss: one group was treated with daily intake of LDA, and the second group was treated with placebo.

Their results suggest that maternal inflammation may be hazardous to the conceptus or survival of male embryos.

Long-term gender differences between males and females exposed to illicit substances during pregnancy were also detected in neurodevelopmental studies. They found that fetal alcohol spectrum disorder FASD was more prevalent in young boys than in young girls on average They reported an association between low levels of alcohol consumption in the first trimester 1 glass per week and clinically significant childhood mental health problems, more prevalent in girls.

This pattern was replicated with both parent and teacher data collected at two later time points, suggesting that the association persisted into middle childhood.

Ethanol exposure during development impaired social recognition memory in a sexually dimorphic manner; male rats showed a deficit in social recognition memory impaired in all variations of the test, while females had deficit only when the task was more challenging. They suggested that the deficit in ethanol-exposed females may be related to changes in oxytocin receptors in the amygdala.

Furthermore, micrognathia was observed significantly more frequently in the male fetuses. The authors suggested that these may be attributed to sex-related differences in the critical period for organogenesis. Another example is the increased risk of oxidative stress-related congenital malformations in male infants of nondiabetic women compared to females [ 19 ]. Endocrine disruptors: It is well documented for years that prenatal exposure to endocrine disruptors, especially substances with estrogenic or antiandrogenic affects, might adversely affect embryonic sex organ development [ 28 , 29 ].

Indeed, there are many experimental animal studies showing the effects of these agents on the gonads and on the internal and external genitalia.

Of special concern are the effects of substances with estrogenic effects on the development of the testes. They found that monoethylhexyl phthalate decreased the expression of the mRNA of anti-Mullerian hormone by the Sertoli cells and increased the apoptosis of the germ cells [ 28 ]. Later, the same group [ 29 ] reported that bisphenol A decreased the production of testosterone in the human fetal testis.

Valproic acid VPA : Valproic acid is a highly teratogenic anticonvulsant that may also induce autistic-like behavior in human and in rodents. It is therefore used for the experimental induction of autistic-like behavior in mice and rats. Prenatal or early postnatal administration of valproic acid in mice or rats is known to induce neurobehavioral deficits.

The affected animals either offspring of the VPA-treated dams or the animals following early postnatal injection of VPA will exhibit autistic-like behavioral changes and increased oxidative stress in their brains [ 30 , 31 ]. On day 60 we euthanized the animals and carried out biochemical and molecular studies on the prefrontal cortex. VPA induced changes in the redox potential and gene expression in relation to treatment and gender.

VPA-induced oxidative stress was manifested by increased lipid peroxidation and activity of antioxidant enzymes and upregulation of antioxidant gene expression. There were significant differences between males and females, oxidative stress markers being more prominent in females. VPA also induced gender-dependent changes in the expression of many genes related to brain function.

In addition there were behavioral changes typical of autistic-like behavior, but female mice were better than males in social behavior while they were poorer in learning [ 30 , 32 ]. Diseases associated with X chromosome, such as fragile X, Duchenne muscular dystrophy, and Rett syndrome, are more common in males than in females due to the X-linked inheritance pattern.

Therefore in the last decades, the use of gender selection due to preimplantation genetic diagnosis has been significantly increased. These procedures test the polar bodies of eggs or cells from preimplantation embryos following IVF, to diagnose the sex of the embryo or the specific disorder in those affected and select for implantation those that are not, thus preventing the transmission of X-linked genetic disorders [ 33 ].

However, as this can only be done when the mutation is known, it is not feasible for some of the X-linked diseases, in which sexing is still important to prevent morbidity [ 35 ]. In many countries gender selection of nonmedical purpose is prohibited for ethical reasons. The paucity of data relating teratogenic effects to gender seems to result from the difficulties in the accurate anatomical assessment of sex in fetuses or newborns.

Indeed, most studies that investigated the teratogenic effects of drugs or teratogenic substances in pregnancy did not look for gender differences. Although gender is sometimes included as a covariate for the statistical analysis, generally, the biological differences between males and females are barely taken as a factor in such analyses. The ability to easily identify fetal sex will allow a better understanding of the possible gender-related effects of teratogens.

As stated above, there are many hereditary diseases that are gender-specific. The importance of sex identification in these cases was described above. These data emphasize that gender, being male or female, is an important factor that can influence both the vulnerability and the adaptive response of the fetus to prenatal teratogenic exposure or, in cases of sex-associated genetic disorders, to enable choosing the normal embryos.

We will therefore describe the existing methods of sex determination including those developed for clinical purposes and those mainly used for research purposes. TrovaGene is also developing a test for Down syndrome.

Most DNA tests on the market use blood. Raylene Lewis, 34, of College Station, Tex. In , she was told she was having a boy, and she chose a name, bought boy clothes and told everyone. Lewis, who sued Acu-Gen, said she ultimately received a refund. Lawyers for Acu-Gen could not be reached for comment. The Pink or Blue test, which claims 95 percent accuracy at seven weeks and gives refunds for wrong results, appears to meet the standards described in the new study.

Chelsea Wallace, 23, of Okeechobee, Fla. It also helped her plan, she said. Tell us what you think. Please upgrade your browser. See next articles. Newsletter Sign Up Continue reading the main story Please verify you're not a robot by clicking the box. Invalid email address. Please re-enter. Abstract Background: Pregnant women have been curious about the sex of their unborn child.

Materials and Methods: A prospective prenatal sonographic sex determination study on consecutive consenting pregnant women aged years in a private hospital in Benin between August and October Results: The sensitivity Conclusion: Prenatal sonographic sex determination has a high sensitivity index. Keywords: Accuracy, gender determination, prenatal gender, prenatal sex, sex determination, sonographic sex, ultrasound sex. Open in a separate window.

Figure 1. Figure 2. Figure 3. Table 1 Cross-tabulation of the sex as detected during obstetric scans against the actual sex at birth. Table 2 Binary classification tests for ultrasonic detection of male and females sexes respectively. First-trimester determination of fetal gender by ultrasound.

Ultrasound Obstet Gynecol. Pajkrt E, Chitty LS. Prenatal gender determination and the diagnosis of genital anomalies. BJU Int. The use of three-dimensional ultrasound for fetal gender determination in the first trimester. Br J Radiol. Profile of women seeking foetal gender at ultrasound in a Nigerian obstetric population.

Mubuuke AG. An exploratory study of the views of Ugandan women and health practitioners on the use of sonography to establish fetal sex. Pan Afr Med J. The sagittal sign. An early second trimester sonographic indicator of fetal gender. J Ultrasound Med. Natsuyama E. Sonographic determination of fetal sex from twelve weeks of gestation. Am J Obstet Gynecol. Stocker J, Evens L. Fetal sex determination by ultrasound.

Obtet Gynecol. Hypospadias mimicking female genitalia on early second trimester sonographic examination. J Clin Ultrasound. Acta obstet Gynecol Scand. Three-dimensional multiplanar ultrasound for fetal gender assignment: value of the mid-sagittal plane.

Sonographic determination of fetal gender. Can ultrasonography replace amniocentesis in fetal gender determination during the early second trimester? Fetal sex determination by ultrasound scan in the second and third trimesters.

Obstet Gynecol. Sonographic determination of fetal gender before 25 weeks gestation. Ultrasound determination of fetal sex. Birnholz JC. Determination of fetal sex.

N Engl J Med. Syrian women's perceptions and experiences of ultrasound screening in pregnancy: Implications for antenatal policy. Reprod Health Matters. The sonographic identification of fetal gender from 11 to 14 weeks of gestation.

sex determination of unborn foetus

Prenatal sex discernment is the prenatal testing for discerning the unborn of a fetus before birth. Prenatal sex discernment can be performed by preimplantation genetic diagnosis before conception, but this method may not always be classified as prenatal sex discernment because it's performed even before implantation.

Unborn sex determination has caused the Child foetus ratio to go down unborn alarming rates, in India, which is also another factor that led to its banning. On May 1st, sex determination and sex-selective abortion were prohibited. Doctors are forbidden by the state from revealing the sex of unborn babies in an sex to stop prospective parents from finding out the gender of their child and potentially abort or sex babies.

From Wikipedia, the free determination. This determination is about prenatal sex discernment in humans. For foetus uses, see Sex determination. See also: Female infanticide in India. See also: Female infanticide in China. BBC Determination Online. June Ultrasound Obstet Gynecol. Retrieved Categories : Prenatal sex discernment. Sex categories: All articles with unsourced statements Articles with unsourced statements from January Namespaces Article Talk. Views Read Edit View foetus.

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Prenatal sex discernment is the prenatal testing for discerning the sex of a fetus before birth. Prenatal sex determination was banned in India in , under the Pre-conception and Prenatal Diagnostic Techniques (Prohibition of Sex. In the absence of a Y chromosome, the fetus will undergo female This is because of the presence of the sex-determining.

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sex determination of unborn foetus

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sex determination of unborn foetus

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