ChapterⅠ:IADPSG criteria does not completely justifies the diagnosis of GDM,neither its contribution significantly decreasesthe incidenceof Macrosomia.　　Objective:The aim of thisstudy was to knowif;the patient with low glucose intolerancein IADPSG criteria justifies thediagnosis of GDM and toexplore the contribution of GDM and gestational weight gain in fetal macrosomia.　　Methods:Two different studies related to GDM wereincluded. In the first study, 48 random patients who were diagnosed with GDM in 24-31 weeks of pregnancy by OGTT (IADPSG cut offvalues) wereselected on the basis of lesserdegree of glucose intolerance. These patients underwent second OGTT within 2-3 weeks of first test. Out of 48 patients, 18 had normal OGTT after 2ndtest. These 18 patients, throughout their gestational period were observed closely and compared with the normal,30 pregnant patient (control group).　　In second study,first 150 LGA babies(birth weight>4000gm) reported in our hospital, vaginally delivered overa period of 6 monthswere collected. Out of these 150 babies, 41 had GDM mothersout of which 38 had excess weight gain during pregnancyand 109 were normal pregnancies out of which 103 had excess weight gain than recommended.GWG was expressed in absolute terms and relative to published recommendations (11-16kg in non-obese women; 5-9kg in obese women).Body mass index and weight gain during the pregnancy of both the groups were compared using student’sT-test.　　Results:For the first test, the gestational period of the case group was normal and outcome of the baby was no different than that of control group. The mean values of all the data of control group and case group were compared. T-test gave values more than 5％ (P>0.05) suggesting that there is no significant difference between the means of compared categories. Although the 75 gm OGTT with IADPSG criteria is considered the most reliable test in diagnosis of GDM, in our study we found 37.5% of the patient failed to reproduce the same result with the second test with all of them having normal maternal and fetal outcome without any diet control or treatment forGDM.　　For the second test, In 150 macrosomia babies,141 had gain more weight then recommendedduring the pregnancy irrespective of GDM.Themean BMI of GDM mothers and normal pregnancy mothershad no significant difference,suggesting that fetal macrosomia is much more dependent on the weight gain by mother during pregnancy rather thanjustGDM.　　Conclusions:More patients with lesser degree of glucose intolerance is being diagnosed and treated as GDM on the basis of only one positive result of OGTT, with single positive value (IADPSG cut off criteria). This has increased the possibility of many being diagnosedand treated without exact maternal and fetal benefits.While the babiesborn to the women with excessgestational weight gain has higher risk of macrosomiathanjust GDM alone.　　ChapterⅡ: The effects of Chinese second-child policy on the second pregnancy complications: a population study of 919 cases.　　Objective:The implementation of second child policy in china has resulted in the increase number of unplanned second pregnancy and childbirth. In this study, we have discussed how the legalization of second childbirth in china after decades of one child policy hasincreased the factors complicating the second pregnancy and childbirth. The factors, which are most likely to be responsible for second pregnancy complications, were evaluated, with a view tominimizethe risk of complications in the future.　　Methods:919 women were included in the study. Firstly, patients were divided into three groups: according to length of intra pregnancy interval<5 years, 5-9 years and>10 years. These groups were compared for the increased risk in second pregnancy and childbirth complication usingchi square test.Secondly, the multiple risk factors for complicated second birth and complicated second pregnancy wasmodeledusing logistic regression. These factors included total number of abortions, number of abortion during IPI, previous methods of delivery, previous birth complications and previous pregnancy complications.　　Results:Pregnancy complications rate in < 5 group was significantly lower than that of the other two groups (P=0.007, and P=0.000). Pregnancy outcomes were affectedby Age (P=0.048; 95% CI. [1-1.079]), total two abortions (P=0.032; 95% CI. [1.045-2.718]), total five abortions (P=0.039;95% CI. [1.064 12.244]), two miscarriages in intra pregnancy interval (P=0.042; 95% CI. [1.021 2.988]); three miscarriages in intra pregnancy interval (P=0.039; 95% CI. [1.043-5.431]).　　Conclusions:The women who had their second child with the Intra Pregnancy Interval of more than 5 years, with the age more than 35 years and with the multiple number of abortions, were the ones who were mostly affected by the second pregnancy and childbirth complications.