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Variation of sex differentiation
Published in Joseph S. Sanfilippo, Eduardo Lara-Torre, Veronica Gomez-Lobo, Sanfilippo's Textbook of Pediatric and Adolescent GynecologySecond Edition, 2019
Anne-Marie Amies Oelschlager, Margarett Shnorhavorian
Position of the anus in relation to the anal muscle complex: This is important to assess for anorectal malformations. Additionally, the anogenital distance can be measured from the center of the anus to the junction of smooth perineal skin and rugated skin of the posterior convergence of the fourchette. The average length is 1 cm in newborn females and 2 cm in newborn males.43
Testing for Reproductive Hazards from Dermal Exposure
Published in Francis N. Marzulli, Howard I. Maibach, Dermatotoxicology Methods: The Laboratory Worker’s Vade Mecum, 2019
Each litter should be examined on lactation day 0 as soon as possible after delivery to establish the number of live pups, the presence of gross anomalies, and the number of stillbirths. Pups found dead on day 0 should be examined to determine the cause of death. Each live pup should be counted, sexed, and weighed at birth (day 0), and on days 4, 7, 14, and 21 of lactation. The age of vaginal opening and preputial separation should be determined for F1 weanlings selected for mating. If there is a treatment-related effect in the F1 ratio or sexual maturation, anogenital distance should be measured on day 0 for all F2 pups.
Phthalates
Published in Dongyou Liu, Handbook of Foodborne Diseases, 2018
Although the studies examining the relationship between phthalates and their detrimental effects are much more numerous in animals than in humans, there has been increasing research looking at the effects in humans. One of the first studies examining the effect of perinatal exposure to phthalates in humans found reduced anogenital distance in males,59 confirming the findings as shown in animal studies.
Prenatal stress decreases sperm quality, mature follicles and fertility in rats
Published in Systems Biology in Reproductive Medicine, 2019
Diana García-Vargas, Lizbeth Juárez-Rojas, Susana Rojas Maya, Socorro Retana-Márquez
The exposure of pregnant female rats to stressors during the critical period of brain sexual differentiation (gestation days 14–21) can cause intense and long-term postnatal effects in progeny reproduction (Segarra et al. 1991). This is known as prenatal programming of the neuroendocrine system regulating reproduction (Evans et al. 2016). In males, demasculinization and feminization of sexual behavior has been observed (Ward 1972; Weinstock 2001; Gerardin et al. 2005). The demasculinization of sexual behavior in prenatally stressed males is related to the attenuation of the testosterone peak at gestational days 18 and 19 (Ward et al. 2003). Prenatal stress is also correlated with reduced anogenital distance, a decrease in plasma LH, FSH and testosterone levels, as well as delayed testicular descent (Pallarés et al. 2013). Also, an increase in the percentage of TUNEL- and active caspase-3 positive cells (apoptotic index) in testis has been observed (Chen et al., 2013). Whether the alterations in testicular cells affect sperm quality and male fertility remain to be assessed in prenatally stressed males.
Systematic review and quality ranking of studies of two phthalate metabolites and anogenital distance, bone health, inflammation, and oxidative stress
Published in Critical Reviews in Toxicology, 2019
Marina R. Sweeney, Keri G. O’Leary, Zsuzsanna Jeney, Megan C. Braunlin, Herman J. Gibb
A large number of reviews have been published on phthalates and various health outcomes in humans, including autism, reproductive systems, breast cancer, diabetes, and obesity (Goodman et al. 2014; Giulivo et al. 2016; Jeddi et al. 2016; Song et al. 2016). Anogenital distance (AGD), which is, generally, the distance between the anus and genitals, was most recently reviewed in 2014 (Kay et al. 2014). AGD is typically measured on infants, is longer for males, and has been studied in relation to testicular function and male fertility (Eisenberg and Lipshultz 2015). Several papers on AGD and phthalates have been published since 2014, warranting an updated review. Among the health outcomes for which data currently exist but that have not yet been reviewed are bone health, inflammation, and oxidative stress.
Anogenital distance and variability in semen parameters
Published in Systems Biology in Reproductive Medicine, 2018
José J. López-Espín, Consuelo Pérez-Palazón, Ana B. Maldonado-Cárceles, José D. Román-Arias, Jaime Mendiola, Alberto M. Torres-Cantero
Anogenital distance (AGD), the distance from the center of the anus to the genitals, is a sexually dimorphic phenotype in mammals being almost twice as long in males than females [Thankamony et al. 2009]. AGD has been recently associated to reproductive anomalies and male infertility [Eisenberg et al. 2011]. Studies in animals [Foster et al. 2001; Sharpe 2011] and human subjects [Mendiola et al. 2011; Eisenberg et al. 2012b; Dean and Sharpe 2013; Jain and Signal 2013; Thankamony et al. 2014] have shown that a shortened AGD was associated with cryptorchidism [Foster et al. 2001; Mendiola et al. 2011; Sharpe 2011; Eisenberg et al. 2012b; Dean and Sharpe 2013], hypospadias [Foster et al. 2001; Mendiola et al. 2011; Sharpe 2011; Eisenberg et al. 2012b; Hsieh et al. 2012; Dean and Sharpe 2013; Thankamony et al. 2014], lower serum testosterone levels [Foster et al. 2001; Mendiola et al. 2011; Dean and Sharpe 2013], decreased testis size [Dean and Sharpe 2013], lower penile length [Eisenberg et al. 2012a; Dean and Sharpe 2013; Thankamony et al. 2014], poor semen parameters [Eisenberg et al. 2011; Dean and Sharpe 2013; Mendiola et al. 2011], and non-obstructive azoospermia [Eisenberg et al. 2012b].