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There are around 300 million adolescent pregnancies worldwide, accounting for 11% of all births worldwide. Accumulating evidence demonstrates that many adverse perinatal outcomes are associated with adolescent pregnancies. However, how and why these abnormalities occur remain to be defined. In this study, pregnancy at different stages was compared between 25- and 30- day-old and mature female mice. We found that the litter size of adolescent pregnancy is significantly decreased from F1 to F3 generations compared to mature pregnancy. On days 8 and 12 of pregnancy, multiple abnormalities in decidual and placental development appear in F3 adolescent pregnancy. On days 5 and 8, uterine endoplasmic reticulum stress is dysregulated in F3 adolescent pregnancy. Embryo implantation and decidualization are also compromised in adolescent pregnancy. Many genes are abnormally expressed in adolescent estrous uteri. The abnormal endocrine environment and abnormal implantation from uterine immaturity may result in multiple pregnancy failures in adolescent pregnancy. The aim of this study is to shed light on human adolescent pregnancy.

Background: There are around 300 million adolescent pregnancies worldwide, accounting for 11% of all births worldwide. Accumulating evidence demonstrates that many adverse perinatal outcomes are associated with adolescent pregnancies. However, how and why these abnormalities occur remain to be defined. Methods: To compare uterine maturity, implantation, decidualization and placental development between 25-30 days old and 3 months old mature female CD-1 strain mice. Both in vivo mouse pregnancy and in vitro cell culture were used. Western blot, real time RT-PCR, immunostaining and immunofluorescence were used to study the progress of pregnancy during two groups.Results: We found the litter size of adolescent pregnancy is significantly decreased from F1 to F3 generations compared to mature pregnancy. On days 8 and 12 of pregnancy, multiple abnormalities in placental and decidual developments appear in F3 adolescent pregnancy. On days 5 and 8, uterine endoplasmic reticulum stress is dysregulated compared to mature pregnancy. Embryo implantation and decidualization are also compromised in adolescent pregnancy. Many genes are abnormally expressed in adolescent estrous uteri. Conclusion: The uterine immaturities and abnormal implantation may cause multiple pregnancy failures in adolescent pregnancy.

In order to achieve the fault diagnostic and degradation assessment of the electro-hydraulic servo valve, a system of prognostic and health management based on the data-driven approach for the electro-hydraulic servo valve is presented. FMMEA performed in this study considered the degree of sub-components in electro-hydraulic servo valve. In order to use only five parameters to assess the cause of degradation, a physical model of the EH servo valve was built up to simulate the failure modes. The simulation results are very useful because the methods can be applied to assess the cause of degradation such as leakage, jamming, clogging and so on.