The Trends And Characteristics Of Urine Gonadotropin And Sex Hormones In Healthy Children Aged 0-6 Years

Background: Disease of sexual development abnormalities in children(such as precocious puberty and gonadal dysplasia)have caused more and more attention.Serum gonadotropin(Gn)and sex hormones are commonly used laboratory indicators for diagnosing and monitoring curative effects of sexual development disorders in children.However,due to the pulsatile secretion of gonadotropin(Gn)and the large fluctuation of blood sex hormone secretion,random blood collection can only reflect the level of hormones at a certain moment in the body.At the same time,due to the invasiveness of blood collection,it greatly affects the compliance of children and their parents.Urinary gonadotropin(UGn)and urinary sex hormones can reflect the average level of hormones in the body for a certain period of time.The detection of UGn and urinary sex hormones can reflect the functional status of the hypothalamic-pituitary-gonadal axis(HPGA)more accurately than the detection of serum Gn and serum sex hormones.At the same time,Due to its non-invasive and convenient characteristics,urine retention can greatly improve the compliance of children and parents.In recent years,immunochemical chemiluminescence(ICMA)has been used to detect UGn and urinary sex hormones in children with sexual development disorders,and the value has been highlighted.However,little research has been done on the trends and characteristics of UGn and urinary sex hormones changes in healthy children aged 0-6 years.Objective: The first morning urine samples were collected from healthy children aged 0-6 years,urine gonadotropin and sex hormones were determined by immunochemical chemiluminescence,observe the trends and characteristics of urine gonadotropin and sex hormones,and provide preliminary research data for epidemiological investigation and clinical application of of mini-puberty and precocious puberty.Methods: From May 2016 to October 2017,healthy children aged 0 to 6 years old(have no signs of sexual development)from Mashan and Hudai Town communities in Binhu District,Wuxi City,Jiangsu Province were included in this study.According to the Chinese standards of growth of children aged 0-18 years and Tanner staging standards,Children with height ranging from-2 SD to 2 SD together with no developmental characteristics were divided into 12 groups.The first morning urine samples were collected.Urine luteinizing hormone(ULH)and urine follicle stimulating hormone(UFSH)were determined by ICMA,besides,urine estriol(UE3),urine estradiol(UE2),urine testosterone(UT)and urine progesterone(UPro)were determined by ICMA.All the results were showed as median(25th-75 th percentiles).Observe the trends and characteristics of them.Results:(1)A total of 920 children(471 boys and 449 girls)were included.They were divided into 12 groups by age.There were 76,71,59,73,50,73,85,72,88,91,91 and 91 cases in ~3 month,3 month~,6 month~,8 month~,1yr~,1.5 yr~,2 yr~,2.5 yr~,3 yr~,4 yr~,5 yr~,and 6 yr~ group,respectively.(2)The detection rates of ULH in boys and girls was 14.86%(70/471)and 22.94%(103/449)respectively,and the detection rates of UFSH in boys and girls was 99.15%(467/471)and 99.33%(446/449)respectively.The detection rates of UE3 was 96.39%(454/471)and 95.54%(429/449),and the detection rates of UE2 was 99.79%(470/471)and 99.78%(448/449)respectively.The detection rate of boy's UT was 95.12%(448/471).The detection rate of girl's UPro was 97.99%(440/449).(3)The trend of UFSH showed no obvious regularity with age.ULH,ULH/Cr and UFSH/Cr all showed a decreasing trend with increasing age.ULH decreased slowly from 1yr~ group,ULH/Cr and UFSH/Cr decreased slowly from 6 month~ group.(4)The trend of Girl's UFSH showed no obvious regularity with age,ULH/Cr decreased slowly from 2 yr~ group and UFSH/Cr decreased slowly from 5 yr~ group.(5)The trends of UE2,UE3 and UT in boys have no obvious regularity with age,while UE3/Cr,UE2/Cr and UT/Cr all showd a decreasing trend with increasing age.UE2/Cr decreased slowly from 1.5 yr~ group.UE3/Cr and UT/Cr both decreased slowly from 6 month~ group.(6)The trends of UE2,UE3 and UPro in girls have no obvious regularity with age,while UE3/Cr,UE2/Cr and UPro/Cr all showd a decreasing trend with age.UE3/Cr,UE2/Cr and UPro/Cr decreased slowly from 2 yr~ group,6 months ~ group and 3 yr~ group respectively.Conclusion:(1)Children aged 0~6 years old had a decreasing trend of UGn/Cr and urine sex hormones with increasing age,and had the characteristics of gender and hormone.(2)Except small infants,ULH levels in children aged 0 to 6 years were low,and the age and gender characteristics of their levels and trends need to using ICMA testing equipment with a higher detection sensitivity to further study.