Anogenital distance of women in relation to their mother’s gynaecological characteristics before or during pregnancy

A novel triad for the diagnosis of endometriosis, the short anogenital distance combines with high endometrial BCL2 and low endometrial FASL

OBJECTIVE

To investigate the anogenital distance from the upper verge of the anus to the posterior fourchette (AGDAF ), FASL, and BCL2 combination as a reliable and non-invasive tool for the diagnosis of endometriosis.

METHODS

This study included 100 women with endometriosis and 50 women without endometriosis as the control group. All cases underwent history taking, body mass index (BMI) measurement, AGD measurement, and FASL and BCL2 immunohistochemical staining of the eutopic endometrial tissue.

RESULTS

This study included 150 women divided into endometriosis and control groups. Endometriosis cases significantly had shorter AGDAF , 22.9 ± 2.6 mm, compared with the control group, 27.3 ± 3.5 mm (P < 0.001). Lower FASL and higher BCL2 expression were associated with endometriosis (P < 0.001). The combined measurement of AGDAF (cut-off point 24.55 mm) with FASL and BCL2 was associated with endometriosis (P < 0.001). The combined diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of AGDAF , FASL, and BCL2 were 83%, 78%, 87.3%, and 69.6%, respectively. The area under the curve was greater for AGDAF , FASL, and BCL2 in combination than for individual measurements.

CONCLUSION

Combining short AGDAF with high BCL2 and low FASL is a highly sensitive, non-invasive diagnostic tool for endometriosis.

Longer anogenital distance in female fetus of diabetic and obese pregnant women

OBJECTIVE

Previous studies revealed that prenatal exposure to androgen excess such as polycystic ovary syndrome (PCOS) is associated with offspring's anogenital distance (AGD) length, and AGD is a biomarker of intrauterine androgen exposure. This study aims to investigate a possible relationship of fetal AGD with maternal diabetes and obesity, and to evaluate whether AGD predicts the fetal androgen exposure related to diabetes and obesity in female fetus. This study is the first to focus on the relationship between offspring's AGD and maternal diabetes and obesity.

MATERIALS AND METHODS

This is a prospective study investigating 218 pregnant women (125 in control group and 93 in study group). Fetal AGD was measured from the center of anus to the posterior convergence of the fourchette by ultrasound. Multivariate linear regression analysis was applied to assess the association of the fetal AGD length with maternal diabetes and obesity.

RESULTS

The control patients had significantly shorter fetal AGD (mean:10.7 mm, P < 0.001) compared to diabetic, obese and diabetic obese patients (mean: 12.6 mm, 12.8 mm and 12.9 mm, respectively). The results of regression analysis showed that both maternal diabetes and obesity were significantly correlated with longer AGD in female fetus. The results confirmed also that offspring's AGD measurement in utero by ultrasound is feasible and reliable.

CONCLUSION

The study findings suggest that both maternal diabetes and obesity are associated with intrauterine androgenic milieu during pregnancy, and fetal AGD may be used as a biomarker to predict this effect. This may provide important advantages in terms of early detection of reproductive system abnormalities related to prenatal androgen exposure.

Prenatal Origins of Endometriosis Pathology and Pain: Reviewing the Evidence of a Role for Low Testosterone

Endometriosis is a polygenic, estrogen-dependent, inflammatory disorder of uncertain aetiology associated with pain, infertility and reduced quality of life. While the positive association between endometriosis and estrogen is established, a suite of recent studies has demonstrated an inverse association between the presence of endometriosis lesions and levels of testosterone both prenatally and postnatally. The following narrative review provides new insights into the roles of testosterone in the aetiology, diagnosis, and management of endometriosis and associated symptoms, especially pain. A relatively short anogenital distance (AGD) is indicative of lower levels of testosterone during fetal development. A shorter AGD has recently been correlated with both a higher risk of developing endometriosis in adult life, and with known correlates of endometriosis including earlier onset of reproductive cycling, lower ovarian follicle number, lower postnatal testosterone, and premature ovarian insufficiency. During adult life, lower levels of testosterone are positively associated with key comorbidities of endometriosis, including days per month of pelvic pain and increased pain sensitivity. Biochemically, lower levels of testosterone are associated with higher levels of pro-inflammatory IL-1β and lower levels of β-endorphin. In rodents, prenatal administration of testosterone to females reduces their pain sensitivity in adulthood. The emerging convergent links of endometriosis with low prenatal and postnatal testosterone provide evidence of a centrally mediated effect beginning in early prenatal development, and persisting through adult life, with notable effects on pain sensitivity. They generate a novel conceptual framework for understanding, studying and treating this disorder, whereby endometriosis is mediated by a combination of high estrogen in endometrial tissue with low systemic and ovarian testosterone.

Effect of anogenital distance on stress urinary incontinence

Background

To clarify the effect of anogenital distance (AGD) on stress urinary incontinence (SUI) in female patients.

Methods

Charts of patients who admitted to urogynecology polyclinic between December 2020 and February 2021 were analyzed retrospectively. The AGD parameters including anogenital distance from the anus to the clitoris (AGDAC), anogenital distance from the anus to the fourchette (AGDAF) and genital hiatus (GH) were measured. To identify effect of ADG parameters on SUI, patients were divided into the two subgroups (patients with SUI and without SUI). Demographic characteristics of patients and perineal anatomy measurement were compared between groups.

Results

Totally, 256 female patients met study inclusion criteria. In comparison of patients with and without SUI, demonstrated that age, weight, height, and BMI were similar between groups (p = 0.200, p = 0.455, p = 0.131, and p = 0.215, respectively). The AGDAF was measured 22.6 mm in patients with SUI and 25.5 mm in patients without SUI (p = 0.014). In contrast, AGDAC was significantly longer in patients with SUI (81.1 mm vs. 72.2 mm, p = 0.001). Also, GH was significantly longer in patients with SUI (p = 0.016). Multivariate logistic regression analysis revealed that one mm increment in AGDAC and GH, is associated with 1.108- and 1.038-fold time of SUI development risk, respectively (p = 0.001 and p = 0.004). In contrast, decrease in AGDAF is resulted with significantly higher risk for SUI (p = 0.001).

Conclusion

The present study demonstrated that shorter AGDAF, and longer AGDAC and GH were resulted with significantly higher incidence of SUI. Considering the ease and non-invasiveness of anogenital distance measurement, an important implication of the results of current study is that it is a measurement that can be easily performed during routine gynecological and obstetric examinations as a suitable tool for use in the prediction of women who will develop stress incontinence in the future.

Foetal Sonographic Anogenital Distance Is Longer in Polycystic Ovary Syndrome Mothers

Anogenital distance (AGD) is a biomarker for the prenatal hormonal environment. Androgen excess is a key element in polycystic ovary syndrome (PCOS). The aim of this study was to assess the sonographic foetal AGD in a population of PCOS mothers in comparison to the general population. Foetal AGD was measured prospectively by 2D ultrasound in PCOS mothers and compared to prenatal AGD nomograms. The results were interpreted regarding maternal and foetal characteristics. The mean sonographic foetal AGD centile measurement in PCOS mothers was significantly longer in comparison to the general population (86.04% ± 18.22; p < 0.001). Estimated foetal weight and birthweight were appropriate for gestational age and did not correlate with AGD. Sonographic foetal AGD was significantly longer in PCOS diabetic mothers and in those who conceived following assisted reproduction treatments when compared to the general population (p < 0.001). Our results support the role of AGD as a biomarker of the prenatal hormonal environment and provide evidence for the hyperandrogenic effect in PCOS pregnancies on foetal androgenic status and genitalia development.

Anogenital distance in newborn infants conceived by assisted reproduction and natural conception

RESEARCH QUESTION

Does anogenital distance (AGD) differ in newborn infants conceived through assisted reproduction technology (ART) compared with those conceived naturally?

DESIGN

This case-control study looked at anthropometric and anogenital measurements in 247 male and 200 female newborns born after ART (n = 121) or natural conception (n = 326), within 24 h of birth. Anogenital measurements included distance from the centre of the anus to the anterior clitoris (AGDAC) and to the posterior fourchette (AGDAF) in female infants, and from the centre of the anus to the posterior base of the scrotum (AGDAS) and to the anterior base of the penis (AGDAP) in male infants.

RESULTS

ART mothers were older, more likely to be nulliparous and delivered by Caesarean section at an earlier gestational week. AGDAS of male infants was approximately twice the AGDAF of female infants (17.6 ± 5.0 versus 9.1 ± 3.6 mm). AGDAF in female infants conceived by ART compared with those conceived naturally was not significantly different (8.8 ± 3.6 versus 9.3 ± 3.6 mm; P = 0.404). AGDAC were also comparable for both groups (27.4 ± 6.3 versus 27.7 ± 7.1 mm; P = 0.770). In male infants, no significant difference was seen between ART and natural conception groups in terms of AGDAS (17.4 ± 4.6 versus 17.7 ± 5.2 mm, P = 0.742) and AGDAP (37.5 ± 6.6 versus 38.0 ± 6.7 mm, P = 0.589). When adjusted for gestational age, weight, length and head circumference, mode of conception was not associated with differences in any of the anogenital measurements.

CONCLUSIONS

AGD measurements in infants conceived by ART are no different from those of infants conceived naturally.

Review of the Effects of Perinatal Exposure to Endocrine-Disrupting Chemicals in Animals and Humans

Maternal exposure to endocrine-disrupting chemicals (EDCs) is associated with long-term hormone-dependent effects that are sometimes not revealed until maturity, middle age, or adulthood. The aim of this study was to conduct descriptive reviews on animal experimental and human epidemiological evidence of the adverse health effects of in utero and lactational exposure to selected EDCs on the first generation and subsequent generation of the exposed offspring. PubMed, Web of Science, and Toxline databases were searched for relevant human and experimental animal studies on 29 October 29 2018. Search results were screened for relevance, and studies that met the inclusion criteria were evaluated and qualitative data extracted for analysis. The search yielded 73 relevant human and 113 animal studies. Results from studies show that in utero and lactational exposure to EDCs is associated with impairment of reproductive, immunologic, metabolic, neurobehavioral, and growth physiology of the exposed offspring up to the fourth generation without additional exposure. Little convergence is seen between animal experiments and human studies in terms of the reported adverse health effects which might be associated with methodologic challenges across the studies. Based on the available animal and human evidence, in utero and lactational exposure to EDCs is detrimental to the offspring. However, more human studies are necessary to clarify the toxicological and pathophysiological mechanisms underlying these effects.

Ovarian response is associated with anogenital distance in patients undergoing controlled ovarian stimulation for IVF

STUDY QUESTION

Is the length of the anogenital distance (AGD) a biomarker of ovarian reserve and response to controlled ovarian stimulation (COS)?

SUMMARY ANSWER

Shorter AGD is associated with presence of poor ovarian response.

WHAT IS KNOWN ALREADY

Organ development during prenatal life is influenced by the prevailing intrauterine environment, and it has been suggested that nutritional, environmental and toxic factors could affect ovarian reserve set prenatally. AGD is a biomarker of prenatal-hormonal environment and observational studies have shown an association between its length and reproductive parameters in both sexes.

STUDY DESIGN, SIZE, DURATION

This was a prospective cohort study of 437 women treated with IVF/ICSI conducted in a tertiary-care university hospital between January and December 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All women underwent their first COS for IVF/ICSI and reached criteria for oocyte retrieval. Based on the number of oocytes obtained, patients were divided into three groups: poor responders (≤3 oocytes) (n = 50), normoresponders (4-15 oocytes) (n = 332) and high responders (>15 oocytes) (n = 55). Before retrieval, the following patient data were recorded: age, body mass index (BMI), ovarian reserve markers (anti-Müllerian hormone [AMH], antral follicle count [AFC] and follicular stimulation hormone [FSH]), cause of infertility, total doses of gonadotropins used and ovarian sensitivity index (OSI). Patients with previous pregnancies, polycystic ovary syndrome (PCOS), endometriosis and previous ovarian or genital surgery were excluded. Anthropometric biomarkers of AGDAC (anus-clitoris) and AGDAF (anus-fourchette) were measured in all patients under sedation on the day of retrieval and before proceeding to oocyte pick-up. Multiple linear regression analyses were used to examine the association between both AGD and ovarian reserve markers, the total units of gonadotropins used, the number of oocytes obtained and the OSI. Logistic regression was used to predict poor response in COS for IVF/ICSI, while accounting for confounders such as age and BMI.

MAIN RESULTS AND THE ROLE OF CHANCE

Baseline FSH, AMH, AFC and age were significantly different among the three groups of ovarian response, as were the units of gonadotropin used, and the ovarian sensitivity index (OSI) (P < 0.001). Both AGDAC and AGDAF measurements were positively correlated with AMH levels (r = 0.38 and r = 0.21; P < 0.05), AFC (r = 0.41 and r = 0.20; P < 0.05), the OSI (r = 0.24 and r = 0.19; P < 0.05) and the number of oocytes retrieved (r = 0.29 and r = 0.28, respectively; P < 0.05). Conversely, there was a negative correlation between both AGD measurements and the doses of gonadotropins used (r= -0.19 and r= -0.15; P < 0.05). The area under the curve (AUC) for prediction of poor response of AGDAC was 0.70 (95% CI 0.66, 0.75), which was comparable to the classic ovarian reserve markers, such as AFC and AMH. AGDAF showed a significantly worse predictive capacity for poor ovarian response (AUC 0.60 [95% CI 0.55, 0.60]) than AMH and AFC.

LIMITATIONS, REASONS FOR CAUTION

The population used for the study was a highly selected group of infertile women who underwent COS for IVF, so the findings of this research may not be applicable for general population. Besides, measurement or selection biases might have been possible and must be considered.

WIDER IMPLICATIONS OF THE FINDINGS

The findings of this study suggest that in utero exposure to certain hormonal environments could affect the ovarian reserve set prenatally.

STUDY FUNDING/COMPETING INTEREST(S)

None. The authors have no competing interests to declare.

Anogenital distance is determined during early gestation in humans

STUDY QUESTION

Does cord blood androgen level obtained at birth affect the AGD in human newborns?

SUMMARY ANSWER

In human newborns, though males have a significantly longer AGD compared to females (as early as 22 weeks of gestation) the AGD is not affected by androgen levels at birth in both the sexes.

WHAT IS KNOWN ALREADY

Animal studies have reported a critical time period in early fetal life, termed the masculinization programming window (MPW) during which AGD is fixed by in utero androgen action and is unaffected by testosterone levels later during gestation. Thus, AGD may serve as a lifelong biomarker of androgen exposure during this window. This MPW is hypothesized to occur in humans at 8-14 weeks of gestation during which AGD is fixed. The effect of androgens (testosterone) on AGD after the MPW in humans is not known. Furthermore, altered AGD has been associated with various human reproductive health disorders in both males and females.

STUDY DESIGN, SIZE, DURATION

A prospective descriptive cohort study was performed using data from randomly selected neonates (n = 205) born at a single center over a period of 1 year (August 2015 to August 2016).

PARTICIPANTS/MATERIALS, SETTING, METHODS

AGDs in male (n = 117) and female infants (n = 88) together with penile width, glans girth and stretched penile length were measured by trained caregivers. Gestation ranged from 22 to 41 weeks and infants were examined within 24 h of birth (within 48-72 h in very sick preterm infants after clinical stabilization). AGD-1 was measured from the center of the anus to the posterior base of scrotum in males or to the posterior fourchette in females. AGD-2 was measured from the center of the anus to the anterior base of the penis in males or to the clitoris in females. Sex steroid hormones (testosterone, 17-OH progesterone (17-OHP) and androstenedione) were measured in serum prepared from umbilical cord blood samples taken at birth, using liquid chromatography-tandem mass spectrometry.

MAIN RESULTS AND THE ROLE OF CHANCE

Males had a significantly lower gestational age (mean ± SD; 34.6 ± 4.9 versus 36.1 ± 4.1 weeks, P = 0.04), and a significantly longer AGD-1 (mean ± SD; 21.6 ± 6.0 versus 12.7 ± 3.8 mm, P < 0.001) and AGD-2 (41.9 ± 8.7 versus 33.9 ± 7.1 mm, P = 0.004) compared to female infants, respectively. The cord serum testosterone levels were significantly higher for male than female infants [median, interquartile range; 13.0 (7.3, 20.5) versus 4.1 (2.5, 5.9), ng/dl, P < 0.001]. There was no difference in levels of 17-OHP (P = 0.697) or androstenedione (P = 0.601) between the two sexes. On multiple regression analysis after adjusting for potential confounders, none of the AGD's in both males and females correlated with any sex steroid hormonal levels. We also provide normative charts for penile length, penile width and glans girth in preterm and term infants.

LIMITATIONS, REASONS FOR CAUTION

No data were collected on family history of genital malformation, infertility or hormonal disorders, parental endocrine-disrupting chemical exposure or diet pattern, any of which might have influenced the AGD and/or sex steroid hormone levels in the offspring.

WIDER IMPLICATIONS OF THE FINDINGS

Our results suggest that AGD in humans, like animals, is fixed in early gestation (likely during the hypothesized MPW) and is unaffected by androgen levels thereafter. Thus, AGD can serve as a biomarker of in utero androgen action during early gestation (likely 8-14 weeks) in humans. As such, causes of human newborn and adult reproductive health disorders, such as endocrine disruptors, should be explored during early gestation. However, further larger studies are needed to help corroborate these findings.

STUDY FUNDING/COMPETING INTERESTS

No specific funding was obtained for this study, and all authors have no conflict of interest to declare.

Assessment of anogenital distance as a diagnostic tool in polycystic ovary syndrome

RESEARCH QUESTION

Is anogenital distance (AGD) a useful clinical tool for predicting polycystic ovarian syndrome (PCOS) and its main National Institutes of Health (NIH) phenotypes?

DESIGN

Case-control study conducted between September 2014 and May 2016 at the Department of Obstetrics and Gynecology of the University Clinical Hospital 'Virgen de la Arrixaca' in the Murcia region (south-eastern Spain). One hundred and twenty-six cases of PCOS and 159 controls without PCOS were included. AGD measurements were taken from the anterior clitoral surface to the upper verge of the anus (AGD_AC), and from the posterior fourchette to the upper verge of the anus (AGD_AF). Parametric and non-parametric tests and receiver operating characteristic (ROC) curves were used to assess associations between AGD and the presence of PCOS and its phenotypes.

RESULTS

AGD_AC, but not AGD_AF, was associated with PCOS and all its phenotypes (P-values < 0.001 to 0.048). The highest area under the curve (0.62; 95% confidence interval 0.55 to 0.71) was obtained for all PCOS with AGD_AC with a sensitivity and specificity of 50.0% and 73.0%, and positive and negative predictive value of 59.0% and 64.4%, respectively.

CONCLUSIONS

AGD_AC could moderately discriminate the presence of PCOS and may be a useful clinical tool.

Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse (POP) Quantification System

Anogenital distance (AGD) is a sexually dimorphic attribute, twice longer in males than in females, and a marker of intrauterine hormonal environment. Interest in AGD measurements is increasing due to mounting evidence on their potential clinical implications. A parallel set of perineal measurements, the Pelvic Organ Prolapse Quantification System (POP-Q), include similar, but not exactly the same, landmarks: the perineal body (PB) and the genital hiatus (GH) lengths. However, clinical reproducibility of both perineal measurements and their usefulness to describe perineal anthropometry needs to be elucidated. To our knowledge, there is no publication in video format showing the methodology of these measurements. The main objective of this work is to show how to properly perform perineal anthropometry, including measurements of the AGD in its two variants [anoclitoral (AGDAC) and anofourchette (AGDAF)], genital hiatus (GH) and perineal body (PB). Moreover, we explored if there were differences in these measurements in women with and without Pelvic Organ Prolapse (POP). We research whether the anthropometric characteristics of the perineum, such as AGD (which is determined prenatally), may be altered in these women and be an independent etiological factor for pelvic floor dysfunction. We show two different ways of measuring perineal lengths, as they might be quite comparable. Our suggestion is that unifying perineal measurements could be useful for clinical and biomedical investigation. More studies are needed in order to compare GH and PB measurements and its AGD counterparts to analyze which procedures are more reproducible with less intra and interobserver variability.

Clustering of PCOS-like traits in naturally hyperandrogenic female rhesus monkeys

Study question

Do naturally occurring, hyperandrogenic (≥1 SD of population mean testosterone, T) female rhesus monkeys exhibit traits typical of women with polycystic ovary syndrome (PCOS)?

Summary answer

Hyperandrogenic female monkeys exhibited significantly increased serum levels of androstenedione (A4), 17-hydroxyprogesterone (17-OHP), estradiol (E2), LH, antimullerian hormone (AMH), cortisol, 11-deoxycortisol and corticosterone, as well as increased uterine endometrial thickness and evidence of reduced fertility, all traits associated with PCOS.

What is known already

Progress in treating women with PCOS is limited by incomplete knowledge of its pathogenesis and the absence of naturally occurring PCOS in animal models. A female macaque monkey, however, with naturally occurring hyperandrogenism, anovulation and polyfollicular ovaries, accompanied by insulin resistance, increased adiposity and endometrial hyperplasia, suggests naturally occurring origins for PCOS in nonhuman primates.

Study design, size, duration

As part of a larger study, circulating serum concentrations of selected pituitary, ovarian and adrenal hormones, together with fasted insulin and glucose levels, were determined in a single, morning blood sample obtained from 120 apparently healthy, ovary-intact, adult female rhesus monkeys (Macaca mulatta) while not pregnant or nursing. The monkeys were then sedated for somatometric and ultrasonographic measurements.

Participants/materials, setting, methods

Female monkeys were of prime reproductive age (7.2 ± 0.1 years, mean ± SEM) and represented a typical spectrum of adult body weight (7.4 ± 0.2 kg; maximum 12.5, minimum 4.6 kg). Females were defined as having normal (n = 99) or high T levels (n = 21; ≥1 SD above the overall mean, 0.31 ng/ml). Electronic health records provided menstrual and fecundity histories. Steroid hormones were determined by tandem LC-MS-MS; AMH was measured by enzymeimmunoassay; LH, FSH and insulin were determined by radioimmunoassay; and glucose was read by glucose meter. Most analyses were limited to 80 females (60 normal T, 20 high T) in the follicular phase of a menstrual cycle or anovulatory period (serum progesterone <1 ng/ml).

Main results and the role of chance

Of 80 monkeys, 15% (n = 12) exhibited classifiable PCOS-like phenotypes. High T females demonstrated elevations in serum levels of LH (P < 0.036), AMH (P < 0.021), A4 (P < 0.0001), 17-OHP (P < 0.008), E2 (P < 0.023), glucocorticoids (P < 0.02-0.0001), the serum T/E2 ratio (P < 0.03) and uterine endometrial thickness (P < 0.014) compared to normal T females. Within the high T group alone, anogenital distance, a biomarker for fetal T exposure, positively correlated (P < 0.015) with serum A4 levels, while clitoral volume, a biomarker for prior T exposure, positively correlated (P < 0.002) with postnatal age. Only high T females demonstrated positive correlations between serum LH, and both T and A4. Five of six (83%) high T females with serum T ≥2 SD above T mean (0.41 ng/ml) did not produce live offspring.

Large scale data

N/A.

Limitations, reasons for caution

This is an initial study of a single laboratory population in a single nonhuman primate species. While two biomarkers suggest lifelong hyperandrogenism, phenotypic expression during gestation, prepuberty, adolescence, mid-to-late reproductive years and postmenopause has yet to be determined.

Wider implications of the findings

Characterizing adult female monkeys with naturally occurring hyperandrogenism has identified individuals with high LH and AMH combined with infertility, suggesting developmental linkage among traits with endemic origins beyond humans. PCOS may thus be an ancient phenotype, as previously proposed, with a definable pathogenic mechanism(s).

Study funding/competing interest(s)

Funded by competitive supplement to P51 OD011106 (PI: Mallick), by P50 HD028934 (PI: Marshall) and by P50 HD044405 (PI: Dunaif). The authors have no potential conflicts of interest.

Investigation of anogenital distance as a diagnostic tool in endometriosis

An association between anogenital distance (AGD) and endometriosis has been reported, suggesting that AGD may be a useful clinical tool in endometriosis. The predictive ability of AGD of women in discriminating presence and type of endometriosis was examined. A case-control study was conducted at the University Hospital 'Virgen de la Arrixaca', Murcia, Spain, between 2014 and 2015. A total of 114 participants diagnosed with endometriosis using ultrasound findings and 105 controls were recruited. Two AGD measurements were obtained: one from the anterior clitoral surface to the upper verge of the anus (AGD_AC), and another one from the posterior fourchette to the upper verge of the anus (AGD_AF). Parametric and non-parametric tests andreceiver operator characterstic analyses were used to determine relationships between AGD and presence of endometriosis and subgroups (ovarian endometriomas or deep infiltrating endometriosis [DIE]). The AGD_AF, but not AGD_AC, was associated with presence of endometriomas, DIE (P-values, <0.001-0.02), or both. The highest area under curve (0.91; 95% CI 0.84 to 0.97) was obtained for the DIE subgroup with the AGD_AF measurement, with a sensitivity and specificity of 84.4% and 91.4%, respectively. AGD_AF can therefore efficiently discriminate the presence of DIE and may be a useful clinical tool.

Comparison of the anogenital distance and anthropometry of the perineum in patients with and without pelvic organ prolapse

OBJECTIVES

To determine whether there are differences in the anthropometric measures of the perineum for women with symptomatic pelvic organ prolapse who are candidates for surgery, with or without urinary incontinence, and for patients without pelvic floor dysfunction. The main objective was to measure the anogenital distance in its 2 variants: anoclitoral and anofourchette. The anogenital distance appears to be determined prenatally and is influenced by the intrauterine hormonal environment. The secondary objective was to measure the length of the genital hiatus, the perineal body and the distance between the 2 ischial tuberosities.

MATERIAL AND METHODS

An observational case-control study was conducted with 58 patients. The cases (n=22) were patients with stages >II 2 in the Baden-Walker classification system. The controls were patients with normal pelvic floors. Measurements were performed with a digital calliper. The patients' tocogynecological history, lifestyle habits and risk factors were recorded.

RESULTS

The case patients had a significantly shorter anogenital anofourchette distance than that of the control patients (P=.001), a significantly longer anogenital anoclitoral distance than the control patients (P=.0001) and a significantly longer genital hiatus length than the control patients (P=.02).

CONCLUSIONS

This was an observational study with a small sample. We cannot determine whether the difference in these distances are caused by or are the result of this disease. Given that the anogenital distance appears to be determined prenatally, we question whether this changed distance could be a risk factor for developing pelvic floor dysfunction.

Endometriomas and deep infiltrating endometriosis in adulthood are strongly associated with anogenital distance, a biomarker for prenatal hormonal environment

STUDY QUESTION

Is the length of the anogenital distance (AGD), a biomarker of the in-utero prenatal hormonal environment, associated with the presence of endometriomas and deep infiltrating endometriosis (DIE)?

SUMMARY ANSWER

Shorter AGD is associated with presence of endometriomas and DIE.

WHAT IS KNOWN ALREADY

It is debated whether hormonal exposure to estrogens in utero may be a risk factor for endometriosis in adulthood. AGD is a biomarker of prenatal hormonal environment and observational studies have shown an association between AGD and reproductive parameters in both sexes.

STUDY DESIGN, SIZE, DURATION

This case–control study of 114 women with endometriosis (endometriomas and/or DIE) and 105 controls was conducted between September 2014 and May 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Cases were attending the Endometriosis Unit of the Hospital. Prevalent as well as incident cases, diagnosed by transvaginal ultrasound (TVUS), were included. Controls were women without endometriosis attending the gynecological outpatient clinic for routine gynecological exams. Participants completed health questionnaires, followed physical and gynecological examinations, including TVUS. Measurements from the anterior clitoral surface to the upper verge of the anus (AGD_AC), and from the posterior fourchette to the upper verge of the anus (AGD_AF) were obtained in all subjects. Unconditional multiple logistic regression was used to estimate the association between AGD measurements and presence of endometriomas and/or DIE while accounting for important confounders and covariates, including age, body mass index, vaginal delivery or episiotomy.

MAIN RESULTS AND THE ROLE OF CHANCE

AGD_AF was related to presence of endometriomas and/or DIE. For all cases of endometriosis (endometriomas and DIE), women in the lowest tertile of the AGD_AF distribution, compared with the upper tertile, were 7.6-times (95% CI 2.8–21.0; P-trend < 0.001) more likely to have endometriosis. With regard to DIE, women with AGD_AF below the median, compared with those with AGD_AF above the median, were 41.6-times (95% CI 3.9–438; P-value = 0.002) more likely to have endometriosis.

LIMITATIONS, REASONS FOR CAUTION

In case–control studies, information and selection bias has to be ruled out. Physicians conducting the measurement were blind to the status of the patients. Controls came from the same population as the cases. We adjusted for known and suspected confounders and covariates, but the possibility of residual confounding or chance findings should always be considered. As with all observational studies, causal inference is limited.

WIDER IMPLICATIONS OF THE FINDINGS

This study suggests that endometriosis, especially the DIE, might have a prenatal origin that may be traced back to the hormonal milieu in which the fetus develops.

STUDY FUNDING/COMPETING INTEREST

This work was supported by the Ministry of Economy and Competitiveness, ISCIII (AES), grant no. PI13/01237 and the Seneca Foundation, Murcia Regional Agency of Science and Technology, grant no. 19443/PI/14. The authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

Not applicable.

The fetal ovary exhibits temporal sensitivity to a 'real-life' mixture of environmental chemicals

The development of fetal ovarian follicles is a critical determinant of adult female reproductive competence. Prolonged exposure to environmental chemicals (ECs) can perturb this process with detrimental consequences for offspring. Here we report on the exposure of pregnant ewes to an environmental mixture of ECs derived from pastures fertilized with sewage sludge (biosolids): a common global agricultural practice. Exposure of pregnant ewes to ECs over 80 day periods during early, mid or late gestation reduced the proportion of healthy early stage fetal follicles comprising the ovarian reserve. Mid and late gestation EC exposures had the most marked effects, disturbing maternal and fetal liver chemical profiles, masculinising fetal anogenital distance and greatly increasing the number of altered fetal ovarian genes and proteins. In conclusion, differential temporal sensitivity of the fetus and its ovaries to EC mixtures has implications for adult ovarian function following adverse exposures during pregnancy.

Human anogenital distance: an update on fetal smoke-exposure and integration of the perinatal literature on sex differences

STUDY QUESTION

Do sex and maternal smoking effects on human fetal anogenital distance (AGD) persist in a larger study and how do these data integrate with the wider literature on perinatal human AGD, especially with respect to sex differences?

SUMMARY ANSWER

Second trimester sex differences in AGD are broadly consistent with neonatal and infant measures of AGD and maternal cigarette smoking is associated with a temporary increase in male AGD in the absence of changes in circulating testosterone.

WHAT IS KNOWN ALREADY

AGD is a biomarker of fetal androgen exposure, a reduced AGD in males being associated with cryptorchidism, hypospadias and reduced penile length. Normative fetal AGD data remain partial and windows of sensitivity of human fetal AGD to disruption are not known.

STUDY DESIGN, SIZE, DURATION

The effects of fetal sex and maternal cigarette smoking on the second trimester (11–21 weeks of gestation) human fetal AGD were studied, along with measurement of testosterone and testicular transcripts associated with apoptosis and proliferation.

PARTICIPANTS/MATERIALS, SETTING METHODS

AGD, measured from the centre of the anus to the posterior/caudal root of penis/clitoris (AGD_app) was determined in 56 female and 70 male morphologically normal fetuses. These data were integrated with current literature on perinatal AGD in humans.

MAIN RESULTS AND THE ROLE OF CHANCE

At 11–13 weeks of gestation male fetal AGD_app was 61% (P< 0.001) longer than in females, increasing to 70% at 17–21 weeks. This sexual dimorphism was independent of growth characteristics (fetal weight, length, gonad weight). We confirmed that at 14–16 weeks of gestation male fetal AGD_app was increased 28% (P < 0.05) by in utero cigarette smoke exposure. Testosterone levels were not affected by smoking. To develop normative data, our findings have been integrated with available data from in vivo ultrasound scans and neonatal studies. Inter-study variations in male/female AGD differences lead to the conclusion that normalization and standardization approaches should be developed to enable confidence in comparing data from different perinatal AGD studies.

LIMITATIONS, REASONS FOR CAUTION

Sex differences, and a smoking-dependent increase in male fetal AGD at 14–16 weeks, identified in a preliminary study, were confirmed with a larger number of fetuses. However, human fetal AGD should, be re-assessed once much larger numbers of fetuses have been studied and this should be integrated with more detailed analysis of maternal lifestyle. Direct study of human fetal genital tissues is required for further mechanistic insights.

WIDER IMPLICATIONS OF THE FINDINGS

Fetal exposure to cigarette smoke chemicals is known to lead to reduced fertility in men and women. Integration of our data into the perinatal human AGD literature shows that more work needs to be done to enable reliable inter-study comparisons.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by grants from the Chief Scientist Office (Scottish Executive, CZG/1/109 & CZG/4/742), NHS Grampian Endowments (08/02), the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement no 212885 and the Medical Research Council, UK (MR/L010011/1). The authors declare they have no competing interests, be it financial, personal or professional.