Search

Objective: The relationship between sex hormone concentrations during childhood and birth weight (BW) is poorly understood. We aimed to investigate this relationship and the associations with anthropometric data at 5, 6, 7, 8, and 10 years of age in preterm boys. Design: A prospective longitudinal single‐centre study, including 58 boys with a BW of 1325–3320 g and gestational age (GA) of 32 + 2 to 36 + 6 weeks. Patients and Measurements: Data on GA, BW and anthropometric data between 5 and 10 years of age were recorded. Testicular development was assessed at 8 and 10 years of age. Serum concentrations of sex steroids were analysed with gas chromatography‐tandem mass spectrometry at 5–10 years and luteinizing hormone (LH) and follicle‐stimulating hormone (FSH) with immunoassays at 10 years of age. Results: At 8 years of age, testosterone and estrone correlated negatively with BW, (ρ = −0.35, p =.021) and (ρ = −0.34, p =.024), respectively. At 10 years of age, testosterone, dihydrotestosterone, estrone and estradiol correlated negatively with BW (ρ = −0.39, p =.010), (ρ = −0.38, p =.013), (ρ = −0.44, p =.003) and (ρ = −0.36, p =.019), respectively. Weight gain from birth correlated with testosterone at 5 years (ρ = 0.40, p =.002), 7 years (ρ = 0.30, p =.040), 8 years (ρ = 0.44, p =.003) and 10 years (ρ = 0.40, p =.008) of age. At 10 years of age, testosterone correlated with LH (ρ = 0.42, p =.006) and FSH (ρ = 0.33, p =.033) but not with testicular volume. Conclusions: Lower BW was associated with increased sex steroid concentrations from 8 years of age, independently of clinical signs of puberty. [ABSTRACT FROM AUTHOR]

Context: There is a lack of knowledge on longitudinal sex steroid patterns during infancy, especially for boys born preterm or with low birth weight (LBW). Objective: To find out whether LBW boys have a disturbed sex steroid profile during infancy. Design and setting: Population-based longitudinal study performed at Sahlgrenska University Hospital, Gothenburg, Sweden. Participants: Ninety-eight singleton boys (47 LBW) born at gestational age 32.0 to 36.9 weeks were included. Because of dropout, 83 of the boys were still in the study at 10 months' corrected age. Main outcome measures: Serum androgen and estrogen concentrations were analyzed by gas chromatography-tandem mass spectrometry and IGF-I was determined with radioimmunoassay in umbilical cord and at 0, 2, 5, and 10 months' corrected age. Results: Serum levels of androstenedione, estrone, and estradiol declined gradually from birth to 10 months corrected age. In both LBW boys and their counterparts, a surge was seen at 2 months' corrected age (3 months' chronological age) for testosterone, median (range) 6.5 (2.0-18.9) nmol/L, and in dihydrotestosterone 1.2 (0.4-4.3) nmol/L. At birth, LBW boys had higher median testosterone (0.7 vs 0.4 nmol/L, P = 0.019), and at 0 months' corrected age, both had higher testosterone (5.7 vs 3.5 nmol/L, P = 0.003) and dihydrotestosterone (1.2 vs 0.9 nmol/L, P = 0.006) than their counterparts. At 10 months' corrected age, catch-up in weight SD score from birth correlated with testosterone (rho = 0.27, P = 0.044) and androstenedione (rho = 0.29, P = 0.027). Conclusions: Moderately to late preterm LBW boys showed a disturbed sex hormone profile, with elevated concentrations of androgens in early infancy. [ABSTRACT FROM AUTHOR]

Highlights • A GC–MS/MS based method for quantification of sex steroids in children is presented. • Adrostenedione, dihydrotestosterone, testosterone, estrone, estradiol were analyzed. • The GC–MS/MS- based method was sensitive enough for use in pediatric applications. • Reference intervals were established in relation to sex and pubertal maturation. Abstract Background Androgen and estrogen determinations serve as important diagnostic markers in a variety of clinical conditions. However, one challenge is to enhance assay sensitivity for determination in the lowest range, such as in prepubertal children. We here present a recently developed gas chromatography–tandem mass spectrometry (GC–MS/MS) method for determination of androstenedione (A 4), dihydrotestosterone (DHT), testosterone (T), estrone (E 1), and estradiol (E 2) in children, which we have compared with the sensitive radioimmunoassays; E 2 extraction-RIA and T-RIA. Methods Steroids were extracted in ethyl acetate n-hexane solution from serum spiked with isotopically labeled internal standard and derivatized sequentially with pentafluorobenzyl bromide, pentafluorobenzyl hydroxylamine and pentafluoropropionic acid anhydride and analyzed by GC–MS/MS using a triple quadrupole mass spectrometer operated in negative chemical ionization mode. Leftover routine samples (n = 414) were used to evaluate the concordance between GC–MS/MS and RIAs and the validity of GC–MS/MS for pediatrics; of these samples, 101 were from seemingly healthy children. Pubertal stage was recorded for reference interval evaluation. Results Lower limit of detection for A 4 , T, DHT, E 1 , and E 2 were 0.1 nmol/L, 0.1 nmol/L, 27 pmol/L, 9 pmol/L, and 2 pmol/L, respectively. Good agreement was found between GC–MS/MS and T-RIA (r = 0.98) as well as between GC–MS/MS and E 2 extraction-RIA (r = 0.98, for E 2 concentrations above 14 pmol/L). In boys, T and DHT increased significantly from prepuberty throughout pubertal development, and in girls the same increase was observed for E 1 and E 2. The greatest increase in A 4 for both genders, as well as E 1 and E 2 in boys and T and DHT in girls, occurred in mid to late puberty. Conclusions We report the development of a GC–MS/MS method sensitive enough to accurately determine serum levels of androgens and estrogens in children. [ABSTRACT FROM AUTHOR]