Fetal penile length

Prenatal phthalate exposure and fetal penile length and width

BACKGROUND

Phthalates are endocrine-disrupting chemicals with anti-androgenic qualities and studies reported associations between prenatal phthalate exposure and infant genitalia. This study investigated whether increased prenatal phthalate exposure is associated with decreased fetal penile measures.

METHODS

Data was from the New York University Children's Health and Environment Study (2016-2019). Maternal urinary concentrations of 16 phthalate metabolites were quantified at <18 weeks gestation as a proxy for fetal exposure (n = 334 male pregnancies). We retrospectively measured penile length and width using ultrasounds conducted 18-24 weeks gestation (n = 173 fetuses). Associations of maternal urinary levels of phthalates with fetal penile length and width were determined using linear regression models.

RESULTS

57.2% of women were Hispanic, 31.8% Non-Hispanic White, 6.4% Asian, 2.3% Non-Hispanic Black, and 2.3% multiple races. Mean maternal age was 32 years (standard deviation [SD] = 5.7). Mean penile length was 7.13 mm (SD = 1.47) and width was 6.16 mm (SD = 0.87). An inverse relationship was observed between maternal levels of mono-ethyl phthalate and fetal penile length, and mono-(7-carboxy-n-heptyl) phthalate and penile width, though estimates were small and not significant when considering correction for multiple comparisons.

CONCLUSIONS

In our cohort we found no clinically meaningful associations between early pregnancy phthalate exposure and fetal penile length or width.

IMPACT

First-trimester phthalate metabolites were assessed in pregnant women in New York City. Penile length and width were retrospectively measured on clinically assessed ultrasounds conducted ≥18 weeks and <24 weeks of gestation. In this cohort, no clinically meaningful associations were observed between first-trimester prenatal phthalate exposure and fetal penile length. This study contributes to the limited but growing research on the impact of prenatal phthalate exposure on male fetal genital development. The results emphasize that there may not be a clear association between prenatal phthalate exposure and fetal penile length and width, and further research on this topic may be required.

Prenatal androgen exposure and sex-typical play behaviour: A meta-analysis of classic congenital adrenal hyperplasia studies

Thousands of non-human mammal experiments have demonstrated that early androgen exposure exerts long-lasting effects on neurobehavioural sexual differentiation. In humans, females with classic congenital adrenal hyperplasia (CAH) are exposed to unusually high concentrations of androgens prenatally, whereas prenatal concentrations of androgens in males with CAH are largely normal. The current meta-analysis included 20 independent samples and employed multi-level meta-analytic models. Consistently across all 7 male-typical and female-typical play outcomes, in the expected directions, the present study found significant and large average differences between control males and control females (gs = 0.83-2.78) as well as between females with CAH and control females (gs = 0.95-1.08), but differences between males with CAH and control males were mostly negligible and were non-significant for 6 of the 7 outcomes (gs = 0.04-0.27). These meta-analytic findings suggest that prenatal androgen exposure masculinises and defeminises play behaviour in humans. Broader implications in relation to sex chromosomes, brain development, oestrogens, socio-cognitive influences, other aspects of sex-related behavioural development, and gender nonconformity are discussed.

Predictive value of ultrasound in prenatal diagnosis of hypospadias: hints for accurate diagnosis

OBJECTIVES

This study aims to assess the diagnostic accuracy of targeted ultrasound examination in prenatal diagnosis of hypospadias and to evaluate the predictive values of defined ultrasonographic findings of hypospadias.

METHODS

The cases diagnosed with hypospadias in our fetal medicine center were identified on an electronic database. The ultrasound reports, images and hospital records were reviewed retrospectively. The predictive value of prenatal ultrasound diagnosis and the predictive values of each sonographic finding were assessed according to the postnatal clinical examinations.

RESULTS

Thirty-nine cases were diagnosed with hypospadias on ultrasound during the 6 years. Nine fetuses with missing postnatal examination records were excluded. Twentytwo of the remaining fetuses had their prenatal diagnosis of hypospadias confirmed in postnatal examinations, indicating a 73.3 % positive predictive value. Normal external genitalia was detected in postnatal examinations of three fetuses. Five fetuses were diagnosed with other external genital abnormalities, including micropenis (n=2), clitoromegaly (n=2), and buried penis with bifid scrotum (n=1) in postnatal examinations. The positive predictive value of prenatal ultrasound for any external genital abnormality was 90 %.

CONCLUSIONS

Although the positive predictive value of ultrasound for genital anomalies is satisfying, it is slightly lower for the specific diagnosis of hypospadias. This reflects overlapping ultrasound findings of different external genitalia anomalies. Standardized, systematic evaluation of the internal and external genital organs, karyotyping and genetic sex determination are essential to achieve a precise prenatal diagnosis of hypospadias.

Relationship among anogenital distance, adrenal gland volume, and penile length and width at 22-36 weeks of pregnancy

OBJECTIVES

The subject of current work was to determine the relationship of fetal ultrasonographic biomarkers, including anogenital distance (AGD), adrenal gland volume, and penile length and width in mothers with male fetuses at 22-36 weeks of gestation for the assessment of the effect of fetal adrenal gland producing androgens on the male anogenital structures that are exposed to androgen effects as anogenital region and penis.

METHODS

This study is a prospective cross-sectional study conducted in our hospital's outpatient perinatal care unit. One hundred and seventy pregnant women with a male fetus aged 22-36 weeks of gestation were included in the study. The fetal adrenal gland length, width, and depth for the calculation of adrenal volume, AGD, and penile length and width were measured for each participant. The Pearson coefficients were calculated to assess the correlation among these parameters.

RESULTS

The adrenal gland volume had a meaningful, positive moderate relationship with both the AGD (r=0.60) and penile length and width (r=0.57 and r=0.59, respectively; p<0.001). The AGD had a positive, strong correlation with the penile length and width (r=0.74 and r=0.76, respectively; p<0.001).

CONCLUSIONS

The fetal adrenal gland as one of the androgen sources of the fetus is an influencer of the development of the anogenital and penile region. The findings of the current study support that the adrenal gland considerably affects the masculinization of male fetuses, since there were remarkable correlations among the AGD, adrenal gland volume, and penile length and width.

No relationship between prenatal or early postnatal androgen exposure and autistic traits: evidence using anogenital distance and penile length measurements at birth and 3 months of age

BACKGROUND

Autism is more prevalent in males than in females. Hypotheses related to the extreme male brain theory of autism suggest that heightened androgen exposure during early development contributes to autistic traits. Whilst prior research focused mostly on the prenatal period, the current study tests the influences of androgen exposure during both the prenatal and the early postnatal periods on autistic traits during childhood.

METHODS

Anthropometric measures that are putative biomarkers of early androgen exposure were employed. Anogenital distance (AGD) was measured at birth and 3 months of age in boys and girls. Penile length at birth and 3 months of age was also measured in boys. When the children were 9-13 years old, a parent-reported questionnaire (the 10-item children's version of the Autism Spectrum Quotient; AQ-10 Child) was used to assess autistic traits in 97 boys and 110 girls.

RESULTS

There were no significant associations between any of the AGD or penile length measures and scores on the AQ-10 Child in boys, girls or the entire sample.

CONCLUSIONS

The current study provides the first test of whether early measurements of AGD and/or penile length predict subsequent autistic traits. The current findings do not support a relationship between prenatal or early postnatal androgen exposure and autistic traits. The current study augments prior research showing no consistent relationship between early androgen exposure and autistic traits.

Open-legs axial plane: A standardized methodology and reference values for fetal genital biometry in mid-trimester ultrasound

BACKGROUND

Evaluation of the external genitalia is an important part of prenatal ultrasound. However, there is no standardized methodology that includes biometric measurements and normative data to be able to carry out this evaluation.

OBJECTIVE

To develop a standardized methodology for fetal genital biometry and obtain reference values for use in mid-trimester ultrasound.

STUDY DESIGN

A prospective cross-sectional study was used. 273 male and 253 female fetuses of normal, singleton pregnancies at 18 to 22 weeks were included. Measurements of fetal penis length, penile width and transverse scrotal diameter in male fetuses and bilabial diameter in female fetuses were performed by transabdominal ultrasound. Reference values were calculated for each gestational week.

RESULTS

Realization of the open-legs axial plane is described as a working methodology. Normative data for penile length, penile width, transverse scrotal diameter and bilabial diameter are defined, including mean, minimum and maximum values, range, and 5th, 10th, 90th and 95th percentiles.

CONCLUSIONS

We have provided a standardized methodology using the open-legs axial plane, which would integrate the main measurements. In addition with the normative data constructed from their use, we hope to be able to improve the external genitalia assessment and diagnosis of genital anomalies in mid-trimester ultrasound.

Sonographic measure techniques of fetal penile length

Postnatal penile length is a reliable, standardized, and widely used marker for the diagnosis of genitourinary pathology, as well as genetic and hormonal disorders. In contrast, prenatal diagnosis has not been developed equally and there is a lack of relevant literature. Our objective is to review the studies on fetal penile length, and apply findings to clinical practice. Although the most used technique is the outer penile length, there is no consensus regarding the appropriate technique for prenatal measurement. Several reports have provided reference data with high correlation. However, important issues like poor correlation with post-natal measures or presence of confounding variables are still present. Diagnosis of both a micropenis and macropenis can indicate related pathologies, and this information may benefit parental counseling and facilitate fetal management. Therefore, it is necessary to carry out prospective studies that provide reliable normative data.

Discordant fetal sex on NIPT and ultrasound

Prenatal diagnosis of sex discordance is a relatively new phenomenon. Prior to cell-free DNA testing, the diagnosis of a disorder of sexual differentiation was serendipitous, either through identification of ambiguous genitalia at the midtrimester morphology ultrasound or discovery of genotype-phenotype discordance in cases where preimplantation genetic diagnosis or invasive prenatal testing had occurred. The widespread integration of cfDNA testing into modern antenatal screening has made sex chromosome assessment possible from 10 weeks of gestation, and discordant fetal sex is now more commonly diagnosed prenatally, with a prevalence of approximately 1 in 1500-2000 pregnancies. Early detection of phenotype-genotype sex discordance is important as it may indicate an underlying genetic, chromosomal or biochemical condition and it also allows for time-critical postnatal treatment. The aim of this article is to review cfDNA and ultrasound diagnosis of fetal sex, identify possible causes of phenotype-genotype discordance and provide a systematic approach for clinicians when counseling and managing couples in this circumstance.

A review of penile elongation surgery

Penile elongation surgery is less commonly performed in the public sector, but involves a collaborative approach between urology and plastic surgery. Congenital and acquired micropenis are the classic surgical indications for penile elongation surgery. The goal of intervention in these patients is to restore a functional penis size in order to allow normal standing micturition, enable satisfying sexual intercourse and improve patient quality of life. Many men seeking elongation actually have normal length penises, but perceive themselves to be small, a psychologic condition termed 'penile dysmorphophobia'. This paper will review the anatomy and embryology of congenital micropenis and discuss both conservative and surgical management options for men seeking penile elongation therapy.

In utero gratification behaviour in male fetus

Fetal masturbation has been described previously once in utero but only as a description of an action. Masturbation is well described in infancy and early childhood when they discover that this practice can give them pleasure. Our letter proves that it could begin in utero as a 'gratification behaviour'. We have shown this pattern clearly by using a volumetric rendering mode study. © 2016 John Wiley & Sons, Ltd.

Sonographic Assessment of the Fetal Penile Development

The intrauterine diagnosis of micropenis is an important clue in the discernment of some syndromes and hormonal deficiencies. In this study, we tried to establish reference ranges for the fetal penile length and penile width. This prospective cross-sectional study included 179 healthy singleton male fetus pregnancies that were between 17 and 37 weeks of gestation. Of these pregnancies, the fetal penile length and width were measured using trans-abdominal ultrasound. The correlation coefficients of gestational age with penile measurements were calculated. We observed that as the gestational age increased both the penile length and width increased (p < .0001, correlation coefficients R(2) = 0.854 and R(2) = 0.883; respectively). Reference values of the penile length in the Turkish Population were similar to previously evaluated populations including English, American and Israeli populations. The penile width measurement is a convenient way to diagnose micropenis, but penile width measurement alone might miss some penile abnormalities including chordee and hypospadias.

Modifications of erectile tissue components in the penis during the fetal period

BACKGROUND

The penile erectile tissue has a complex microscopic anatomy with important functions in the mechanism of penile erection. The knowledge of such structures is necessary for understanding the normal physiology of the adult penis. Therefore, it is important to know the changes of these penile structures during fetal development. This study aims to analyze the development of the main components of the erectile tissue, such as collagen, smooth muscle fibers and elastic system fibers, in human fetuses.

METHODOLOGY/PRINCIPAL FINDINGS

We studied the penises of 56 human fetuses aged 13 to 36 weeks post-conception (WPC). We used histochemical and immunohistochemical staining, as well as morphometric techniques to analyze the collagen, smooth muscle fibers and elastic system fibers in the corpus cavernosum and in the corpus spongiosum. These elements were identified and quantified as percentage by using the Image J software (NIH, Bethesda, USA). From 13 to 36 WPC, in the corpus cavernosum, the amount of collagen, smooth muscle fibers and elastic system fibers varied from 19.88% to 36.60%, from 4.39% to 29.76% and from 1.91% to 8.92%, respectively. In the corpus spongiosum, the amount of collagen, smooth muscle fibers and elastic system fibers varied from 34.65% to 45.89%, from 0.60% to 11.90% and from 3.22% to 11.93%, respectively.

CONCLUSIONS

We found strong correlation between the elements analyzed with fetal age, both in corpus cavernosum and corpus spongiosum. The growth rate of these elements was more intense during the second trimester (13 to 24 WPC) of gestation, both in corpus cavernosum and in corpus spongiosum. There is greater proportional amount of collagen in the corpus spongiosum than in corpus cavernosum during all fetal period. In the corpus spongiosum, there is about four times more collagen than smooth muscle fibers and elastic system fibers, during all fetal period studied.

Micropenis: etiology, diagnosis and treatment approaches

Micropenis is a medical diagnosis based on correct measurement of length. If stretched penile length is below the value corresponding to - 2.5 standard deviation of the mean in a patient with normal internal and external male genitalia, a diagnosis of micropenis is considered. Micropenis can be caused by a variety of factors including structural or hormonal defects of the hypothalamic-pituitary-gonadal axis. It can also be a component of a number of congenital syndromes. For the etiological evaluation, endocrinologic tests are important. This article reviews the etiology, diagnosis, treatment and management of micropenis.

Development of the penis during the human fetal period (13 to 36 weeks after conception)

PURPOSE

We analyzed the development of the area of the penis and erectile structures (corpora cavernosa and corpus spongiosum) and the thickness of the tunica albuginea during the fetal period (13 to 36 weeks after conception) in humans to establish normative patterns of growth.

MATERIALS AND METHODS

We studied 56 male human fetuses at 13 to 36 weeks after conception. We used histochemical and morphometric techniques to analyze the parameters of total penile area, area of corpora cavernosa, area of corpus spongiosum, and thickness of tunica albuginea in the dorsal and ventral regions using ImageJ software (National Institutes of Health, Bethesda, Maryland).

RESULTS

Between 13 and 36 weeks after conception the area of the penis varies from 0.95 to 24.25 mm2. The area of the corpora cavernosa varies from 0.28 to 9.12 mm2, and the area of the corpus spongiosum varies from 0.14 to 3.99 mm2. The thickness of the tunica albuginea varies from 0.029 to 0.296 mm in the dorsal region and from 0.014 to 0.113 mm in the ventral region of the corpora cavernosa.

CONCLUSIONS

We found a strong correlation between the total penile area, corpora cavernosa and corpus spongiosum with fetal age (weeks following conception). The growth rate was more intense during the second trimester (13 to 24 weeks of gestation) compared to the third trimester (25 to 36 weeks). Tunica albuginea thickness also was strongly correlated with fetal age and this structure was thicker in the dorsal vs ventral region.

Reference values for fetal penile length and width from 22 to 36 gestational weeks

OBJECTIVE

Current reference range values for fetal penile growth are based on length measurements. However, methodologies for measuring penile length differ among studies and from the standard technique used in children. We propose that the measurement of penile width may aid in its evaluation. The aim of the study was to create normograms for penile length and width.

METHODS

A prospective cross-sectional design was used. One hundred male fetuses at 22 to 36 gestational weeks were included. On ultrasound examination, penile length was measured from tip to base, where the penis joins the scrotum. Penile width was measured at the widest point across the penis. Reference values for the 5th and 95th percentiles were calculated for each gestational week.

RESULTS

There was a good correlation between gestational age and penile length (R(2) = 0.606) and width (R(2) = 0.683). The percentile of fetal weight estimation independently affected penile length and width. The interobserver correlation coefficient was 0.939 for length and 0.909 for width.

CONCLUSION

Reference range values of fetal penile length and width are presented for 22 to 36 weeks of gestation. These values correlate to gestational age and estimated fetal weight percentile. These reference range measurements may help the evaluation of suspected micropenis.

Penile biometry on prenatal magnetic resonance imaging

OBJECTIVE

In view of the implementation of magnetic resonance imaging (MRI) as an adjunct to ultrasonography in prenatal diagnosis, this study sought to demonstrate normal penile growth on prenatal MRI.

METHODS

This was a retrospective study of MRI of 194 male fetuses (18-34 weeks' gestation) with normal anatomy or minor abnormalities. On sagittal T2-weighted MRI sequences, we measured penile length from the glans tip to the scrotal edge (outer length) and from the glans tip to the symphyseal border (total length). Descriptive statistics, as well as correlation and regression analysis, were used to evaluate penile length in relation to gestation. T-tests were calculated to compare mean outer/total length on MRI with published ultrasound data.

RESULTS

Mean length values, including 95% CIs and percentiles, were defined. Penile length as a function of gestational age was expressed by the following regression equations: outer mean length = - 5.514 + 0.622 × gestational age in weeks; total mean length = - 8.865 + 1.312× gestational age in weeks. The correlation coefficients, r = 0.532 and r = 0.751, respectively, were statistically significant (P < 0.001). Comparison of outer penile length on MRI with published ultrasound penile length data showed no significant differences, while total penile length on MRI was significantly greater than ultrasound penile length (P < 0.001).

CONCLUSION

Our MRI results provide a reference range of fetal penile length, which, in addition to ultrasonography, may be helpful in the identification of genital anomalies. Outer penile length on MRI is equivalent to penile length measured on ultrasound, whereas total length is significantly greater.

Sonographic measurement of corpus spongiosum in male fetuses

OBJECTIVE

To establish a nomogram of the corpus spongiosum dimensions in male fetuses and to evaluate its correlation with penile length. These references can be useful when fetal genital anomalies are suspected, particularly to distinguish micropenis from concealed penis cases.

METHOD

A cross-sectional prospective study was conducted on 486 fetuses of normal singleton pregnancies between 18 and 40 weeks. Corpus spongiosum length, penile length, penile diameter and scrotal diameter were measured by one operator. All measurements were analyzed according to gestational age.

RESULTS

The four measurements were studied as a function of gestational age. Median values, 3(rd) and 97(th) percentiles were determined using regression curves. A correlation between penile length and corpus spongiosum length (r(2) = 0.845) was observed.

CONCLUSION

We established measurements of the length of fetal corpus spongiosum and a correlation between the former and the penile length. These references can be useful when fetal genital anomalies are suspected.

Normal growth and development of fetal external genitalia demonstrated by sonography

PURPOSE

Our aim in this retrospective sonographic study was to describe the normal growth and development of fetal external genitalia.

METHODS

We reviewed the sonograms of anatomically normally fetuses, obtained over a 5-year period, and measured transverse scrotal diameter or penile length in male fetuses and bilabial diameter in female fetuses. Transverse scrotal diameter was measured from the midpoint of the lateral scrotal wall to the midpoint of the opposite lateral wall; penile length, from the base of the shaft to the tip; and bilabial diameter, from the midpoint of the lateral labial margin to the midpoint of the opposite lateral labial margin.

RESULTS

We examined sonograms from 1,182 fetuses and measured transverse scrotal diameter in 304 and penile length in 494 male fetuses and bilabial diameter in 384 female fetuses. The fetuses ranged from 14 to 41 weeks' menstrual age. Transverse scrotal diameter, penile length, and bilabial measurements were highly correlated with menstrual age (r = 0.941, r = 0.860, and r = 0.898, respectively). We found that growth of fetal external genitalia is similar to that for other parameters of fetal growth, such as biparietal diameter and femur length.

CONCLUSIONS

The results of this study may be helpful in understanding the natural course of the growth and development of fetal external genitalia. In addition, the data we gathered may be useful in combination with other biometric data for estimating fetal age and may help in detecting abnormalities in the fetal external genitalia.