Measurement Of Fetal Genital Parameters And Prenatal Ultrasonic Evaluation Of Abnormal External Genitalia

Objective: The main results were as follows:(1)using two-dimensional and three-dimensional ultrasound to observe the anterior and posterior diameter of uterus,thickness of clitoris,length of male fetus urethra,and to explore the relationship between the measured values and gestational weeks,and the mean values of the measured values in different gestational weeks.The standard deviation and 95% confidence interval can be used to help diagnose fetal sex and development abnormality.(2)by studying 16 fetuses whose fetal genital abnormalities were suspected by prenatal ultrasound,the ultrasound images and other results of postpartum or induced labor were compared.To study the ultrasonographic features of fetal sex dysplasia.Methods:(1)From September 2017 to January 2019,normal fetuses were examined by prenatal ultrasound in our hospital.The gestational weeks ranged from 19 to 37 weeks,and the number of cases per gestational week ranged from 8 to 15,male fetus and female fetus: a report of 200 cases,with a total of 400 cases.GE Voluson E8 and E10 ultrasonic diagnostic instruments(2-D convex array probe,2-5 MHz frequency,transabdominal three-dimensional volumetric imaging probe,frequency 4-8MHz)were used.Admission criteria: 1.Single pregnancy;2.Pregnant women before pregnancy menstruation(28-30 days);3.No diabetes mellitus,hypertension and other complications;4.Pregnant women have done down screening,non-invasive DNA,No significant abnormality was found in any of the amniocentesis tests.5.There was no family history of hereditary diseases.The anteroposterior diameter and clitoris thickness of normal female fetus and the length of male fetal urethral sponge were measured by two-dimensional ultrasound(hereinafter referred to as urethral length).The TUI and VCI mode were used when the boundary of the viscera was not clear.Store the data and leave a picture.Spss22.0 software was used to analyze the changes of uterine diameter and clitoris thickness in female fetus and the length of urethra of male fetus with gestational week.(2)16 cases of suspected abnormal genitalia : Focus on scanning the fetus’ s external genitals whether there are testis.Whether the inner urethral linear echo of the penis reaches the top of the tortoise head,the external genital ambiguity can not be determined by observing whether there is a uterus in the pelvic cavity,and collecting data and leaving a picture at the same time.Results: Among the 371 fetuses,188 were female(display rate 94%)and 183 were male(display rate 91.5%).The uterine diameter and clitoris thickness of 188 female fetuses and the length of urethral cavernous body of 183 male fetuses varied linearly with gestational weeks.By linear regression analysis,the linear equations were established as follows: Y1(mm)= 0.44X-4.82(Gestational age is an independent variable X,fetal uterine diameter is dependent variable Y1),Y2(mm)= 0.25X-1.69(Gestational age is an independent variable X.Fetal clitoris thickness as dependent variable Y2),Y3(mm)= 1.99X-20.68(Gestational age is an independent variable X,the length of fetal urethral is dependent variable Y3).At the same time,the mean value,standard deviation and 95% confidence interval were provided for each gestational week fetus.(2)of the 16 suspected cases of abnormal external genitalia,2 cases were normal female fetuses,2 cases were female pseudohermaphroditism,and 1 case was bladder valgus.2 cases were simple hypospadias,1 case was hypospadias with bilateral cryptorchidism,1 case was valgus of cloacal cavity,7 cases were penis scrotum transposition with hypospadias.Through the combination of two and three dimensions,the sonographic features of fetal sex dysplasia are obtained: the fetal external genitalia are blurred and the fetal sex can not be accurately distinguished;the fetal penis Urethral linear echo interrupted,not reaching the end of the penis,the end of the penis is abnormal,the end of the obtuse;scrotal division,short penis located in the middle of the split scrotum,"tulip" sign;can be combined with other abnormalities.Conclusion: When the external genitalia of the fetus are ambiguous and unable to distinguish the sex of the fetus,the display of the fetus’ s uterus and testis,the length of the fetal urethra and so on can provide very important information.The anterior and posterior diameter of uterus,thickness of clitoris and length of urethra of male fetus were linearly correlated with gestational weeks.