ESPE Abstracts

Background: Studies have shown that genetic variations in the FSH pathway (SNPs: FSHB −211G>T, FSHR −29G>A, and FSHR 2039A>G) affect peripubertal levels of serum FSH and age at pubertal onset in girls.Objective and hypotheses: Genetic variations in the FSH pathway reflect circulating levels of female reproductive hormones during the postnatal gonadotropin surge.Method: Blood samples were taken in girls of th...

Background: The anogenital distance (AGD) is defined as the distance from the anus to genital tubercle. AGD is an established method for sex determination of pups in rodents, and in animal studies, AGD is strongly affected by androgen exposure during fetal life. In accordance, human studies have reported reduced postnatal AGD following prenatal exposure to anti-androgenic agents, suggesting AGD to be a sensitive postnatal read out of in utero exposure...

Paternally inherited mutations in the DLK1 (delta-like non-canonical Notch ligand 1) gene cause central precocious puberty (CPP) with a metabolic phenotype, suggesting that DLK1 (Delta-like 1 homolog/Preadipocyte factor 1) may link pubertal timing with body composition. However, little is known about circulating DKL1 in normal and precocious puberty.Objective: To evaluate longitudinal changes in circulating DLK1 concentrations i...

Background: Age at onset of puberty exhibits a remarkable variation mirroring nutritional, environmental, socioeconomic and genetic factors. While large genome-wide association studies identified more than hundred genetic loci associated with age at menarche in girls, knowledge on loci associated with age at pubertal onset in boys is sparse. FSHB/FSHR genetic variants have been shown to affect pubertal timing in girls and reproductive parameters in men.<p class="a...

Background: Pubertal gynaecomastia is thought to be a clinical sign of an oestrogen-androgen imbalance, affecting up to 60% of boys. In most cases no underlying endocrinopathy can be identified. In boys, Anti-müllerian hormone (AMH) is produced by immature Sertoli cells and circulating level decreases as testosterone increases during pubertal maturation. In a previous cross sectional study we found significant lower levels of AMH in boys with pubertal gynaecomastia (Mieri...

Background: The male Hypothalamic-Pituitary-Gonadal (HPG) axis undergoes a transient activity phase during the first months of life with surging serum concentrations of reproductive hormones. Theoretically, the hormonal surge could represent a passive postnatal feedback to the withdrawal from the high sex steroid levels in pregnancy. However, we believe that minipuberty rather represents an active, tightly genetically-regulated biological process. We therefore...

Background: In minipuberty, the male hypothalamic-pituitary-gonadal (HPG) axis is transiently activated triggering a surge in reproductive hormones causing growth of the genitalia. Longitudinal individual growth of the infant penis during minipuberty and associations to the HPG axis and IGF-I have not been thoroughly assessed.Aim: To describe the development of penile length and width as well as their relation to serum c...

Background: The circulating steroid metabolome in boys undergoes significant changes during infancy reflecting functional and structural rearrangements of the adrenal glands as well as the transient activity of the hypothalamic–pituitary–gonadal axis, also called minipuberty. Studies investigating the serum steroid metabolome dynamics during infancy in a longitudinal manner are however sparse.Objective: We ai...

Background: The anogenital distance (AGD) is a well-known measure in rodents used to distinguish male and female pubs. Likewise, AGD display sex-specific differences in humans. It is considered a postnatal readout of early androgen exposure in fetal life. Thus, in postnatal life AGD is longer in boys than in girls, reduced in infants born with cryptorchidism and hypospadias as well as in boys exposed to anti-androgenic agents in fetal life. However, little is ...

Background: Growth in infancy is considered primarily to be regulated by nutrition and insulin, whereas less is known about the influence of IGF-I, reproductive hormones and other factors of importance. Recently, paternally inherited genetic defects of DLK1 (Delta-like 1 homolog) were found in girls with central precocious puberty (CPP) with a metabolic phenotype. In addition, low maternal serum DLK1 concentrations were significantly lower in pregnant women wh...