First trimester fetal biometric assessment is very important for the accurate estimation of gestational age to conduct optimal antenatal care. The timings any antenatal diagnostic tests, elective C-section, induction of delivery for postdated pregnancies are based on gestational age. This is the first study to construct the first trimester Mongolian fetal standard biometry which is to answer the following questions; which widespread first trimester fetal nomogram is similar to Mongolian fetal biometry, are there any unique fetal characteristics in Mongolian ethnic groups. In accordance with inclusion and exclusion criteria 658 healthy women between 11-14+6 weeks of gestation examined on the following fetal biometric measurements: biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL). The study occurred between Jan 2013 to April 2014 Combined measurement of abdominal and vaginal examination was done. Physicians who worked for more than 10 years in the field of obstetrical ultrasound are required to do at least three measurements to get correct results.Statistical analysis was performed with SPSS-21, E-View, and Windows Excel. A regression model was developed with biometric measurements and was compared to widespread nomograms in the world.The obtained Mongolian first trimester standard fetal biometry was compared to Hadlock from Europe, M.A.Esetov from the same geographic region, Osaka from Asia, ASUM from the reference of Australia. BPD was 4-6mm longer, HC was 20-13mm longer than Hadlock but it was the same as others. FL was a bit shorter than Hadlock and ASUM but it was the same as Osaka and M.A.Esetov at 12-14+6 weeks of gestation. Difference with the obtained nomograms may be due to ethnic differences of the Mongolian fetal development. Current study shows that there are needs to use separate growth chart to estimate accurate gestational age for Mongolian population.

GoalThis study was performed to construct Mongolian ethnic specific crown-rump length (CRL)nomogram and to compare its ability to predict gestational age with previously published widelyused nomograms in the world.Materials and MethodsA regression model was developed for estimation of gestational age using CRL measurements of1170 singleton fetuses in the Mongolian population. Measurements were obtained by placing thecalipers of the ultrasound machine from the crown to the rump. The appropriateness of previouslyestablished widespread CRL nomograms for predicting the gestational age was assessed in theMongolian population to determine comparability between nomograms.ResultsCRL corresponds to other nomograms up to 9 weeks of gestational age. There is a 4-5mm differenceof Robinson Hadlock; 7mm of Osaka at 10-12 weeks but the same with Campbell, 4 mm long ofCampbell at 13 weeks.Conclusions:CRL measurements are used as a reliable method for estimation of the gestational age as well asa baseline for comparing gestational ages later. CRL corresponds to other widely used nomogramup to 9 weeks gestational age. There is a 3mm differences of M.A.Esetov, 4-5mm Robinson, andHadlock; 7mm of Osaka at 10-12 weeks but the same with Campbell, 4 mm long of Campbell at13 weeks. Difference with the established nomograms may be due to ethnic differences of theMongolian fetal development. After 13 weeks, CRL measurement is unreliable due to flexion of thefetus.

The double and triple test is a prenatal screening used to identify those pregnant women who shouldbe offered a diagnostic test to identify whether their fetus has an aneuploidy. It was first described in1988, but has largely been superseded by newer tests either conducted earlier in the first trimester(ie, the combined test, using ultrasound measurement of nuchal translucency, pregnancy-associatedplasma protein A, and human chorionic gonadotrophin [hCG]) or in the second trimester (ie, thetriple and quadruple test, using α-fetoprotein, hCG, uE3, and inhibin).These newer tests have been introduced because they offer greater detection and lower screenpositive results thereby enhancing diagnosis rates, while decreasing the risk of iatrogenic harmcaused by the invasive testing required when collecting suitable sample tissue. Both first andsecond trimester screening programs have been expanded to include risk assignment for trisomy18. Targeted screening algorithms have not been developed for chromosomal abnormalities otherthan Down syndrome and trisomy 18, although it has been suggested that a trisomy13 risk might becalculated. The construction of such algorithms would require recognition of a characteristic patternfor each condition using the appropriate combination of markers. It is likely, therefore, that the doubleand triple test will continue to be used in routine antenatal care for the foreseeable future.

BACKGROUND. In the world, infertility occurs in 10-15% of the total couples and male infertility accounts for 40-50% of the infertile cases. Infertility frequency in Mongolia is 8.7% in 2003 and 11.6% in 2013. According to the Child and Maternity hospital study, 25.6% of infertility is due to men. Microdeletions of the Y chromosome long arm are the most common molecular genetic causes of severe infertility in men. They affect three regions including azoospermia factors (AZFa, AZFb and AZFc), which contain various genes involved in spermatogenesis. OBJECTIVES. The aim of the present study is to investigate the relationship between sexual hormones and AZF microdeletion on Y chromosome in Mongolian infertile men with azoospermia and severe oligozoospermia. MATERIAL AND METHODS. Through a cross sectional study, 50 infertile men were examined for Y chromosome microdeletions from January 2018 to August 2018. We determined hormone level, testis biopsy and microdeletions of the Y chromosome using six loci of 3 regions of the AZF gene were investigated by multiplex polymerase chain reaction. Semen analysis was performed on samples obtained by self-masturbation at the hospital after 2-7 days of sexual abstinence. Reproductive hormone level in serum including total testosterone, follicular stimulating hormone (FSH), and LH is measured at time 8 am to 11 am. If sperm is not recovered, testicular biopsy was performed on the patient. All collected datas were evaluated with Statistical Package for Social Sciences (SPSS, version 22.0). RESULTS. The rate of microdeletion was 4.0% (2 out of 50 patients). The deletion was on AZFa in the first patient, AZFc in the second patient. The patients with Y chromosome microdeletion had azoospermia. AZFa deleted patient has sertoli cell only syndrome in testis biopsy with FSH 58.0 mIU/ml, LH 12.0 mIU/ml, total testosterone 5.0 ng/ml. AZFc deleted patient had FSH 23.85 mIU/ml, LH 13.01 mIU/ml, total testosterone 4.06 ng/ml. Serum FSH and LH levels were significantly higher in Y chromosome deleted group and FSH level was significantly lower in sperm-retrieved group on TESE. СONCLUSION. We determined 2 cases of Y chromosome microdeletion (4.0%) in infertile men. Serum FSH and LH levels were significantly higher in Y chromosome deleted group.