The study's purpose is to see how useful WHO guidelines are for detecting gestational diabetes (GDM) in pregnant women, as well as how effective they are at minimizing negative repercussions for the mother and newborn in women under the age of 18. In a 35-year-old woman, there were no evident risk issues for GDM. The method used in this retrospective study is based on 1,360 pregnant women that gave birth and were tracked at the hospital in Istanbul University. All participating pregnant women between 24th to 28th week underwent the test for 75g Oral Glucose Tolerance. The WHO’s standard criteria that were already formalized were used to establish whether there was evidence of gestational diabetes in each case. The study included the test of oral glucose tolerance utilized to identify around 28% of pregnant women under 35 who had no risk issues related to GDM complications. The rate of primary caesarean sections in the group with GDM, was radically greater than that in the group without gestational diabetes. Premature birth has also been linked to GDM complications. The observations indicated that the admission to NICU, Neonatal critical care unit, was strongly associated to diagnosis of Gestational Diabetes Mellitus (GDM). In neonates, no substantial concerns with airway anomalies. There is a lot of variation in the groupings. The correlation between metabolic problems and gestational diabetes was moderate. According to the WHO’s criteria, childbearing women with no clear risk issues were identified with GDM. It was studied that treatment for these women may reduce their risk of neonatal and maternal hyperglycemia-related problems like caesarean section, polyhydramnios, premature delivery, NICU admission, LGA, and low infant mass.