Objective To observe and analyze the effects of fetus gestational weeks on efficiency of Down's screening during the second trimester, and to provide certain reference data clinically. Methods A total of 36515 puerpera who received prenatal screening during the second trimester were selected. They were assigned to 5 groups according to their gestational weeks, which were group of 15 gestational weeks(15 to 16+6), group of 16 gestational weeks (16 to 16+6), group of 17 gestational weeks(17 to 17+6), group of 18 gestational weeks (18 to 18+6) and group of 19 ges-tational weeks (19 to 20 weeks). Detection rate and false screening positive rate of infants with Down's syndrome were compared between different gestation weeks. Results Two cases of missed diagnosis were seen in puerpera in the group of 15 gestation weeks. Detection rate of Down's screening in the group of 16 weeks to 18 weeks was 100%. No diagnosed infants with Down's syndrome were seen in the group of 19 gestational weeks. The false positive rate therefore was 7.85%. The screening results were different during different gestational weeks. Detection rate during 16 to 18 gestation weeks was 100%, and false positive rate of screening was 4.36%. In the negative groups of screened puerpera, AFP level increased with the increase of gestational weeks, and HCG level decreased with the increase of gestational weeks. In the positive groups of screened puerpera,their AFP levels were all lower than those in the nega-tive groups,and there HCG levels were higher than those in the negative groups. Conclusion Efficiency of screening is high when Down's screening during the second trimester of pregnancy is carried out during 16 to 18 gestational weeks.

Objective To study the relationship between serum betatrophin and early growth of macrosomia.Method Full-term macrosomia born in the Maternity and Children's Branch of Ruian People's Hospital of Zhejiang Province from January to June 2018 followed up to 6 months and their mother were enrolled in the prospective case-control study as the fetal macrosomia group.The full-term infants appropriate for gestational age,who met all the above requirements were randomly enrolled in the AGA group in a 1∶1 ratio.Enzyme linked immunosorbent assay (ELISA) was used to detect the level of blood betatrophin at birth and 6 months respectively,and the relationship between serum betatrophin level and the growth and development of infants was analyzed.Result A total of 4 823 live births were delivered during the study period,308 of them were full-term macrosomia,the incidence was 6.4％.30 cases were included in the macrosomia group and the AGA group,respectively.The level of blood betatrophin at birth and 6 months in the macrosomia group were higher than that in the AGA Group [(1 088.3 ± 67.8) ng/L vs.(929.5 ± 81.0) ng/L,(1 057.1 ± 114.2) ng/L vs.(976.4 ±76.6) ng/L],and the differences were statistically significant (P ＜ 0.01).The incidence of overweight was 26.7％ (8/30) in the macrosomia group and 6.7％ (2/30) in AGA group at 6 months of age,the difference was statistically significant (P ＜ 0.05).The level of blood betatrophin in overweight infants was statistically significantly higher than that in non-overweight infants (P ＜ 0.001).There was a positive correlation (P ＜ 0.001) between the level of blood betatrophin at the age of 6 months and the weight,body length,Z-score of weight/body length,triglyceride level at birth and the age of 6 months,and the level of umbilical blood betatrophin.But it was not correlated to gender,feeding pattern,other components of blood lipid,blood glucose and insulin in the cord blood and mother's blood,and the level of blood betatrophin in mother's blood (P ＞ 0.05).Conclusion The betatrophin is involved in the regulation of infant growth and development,which is associated with the occurrence of overweight.