Objective: The objective of this study was to investigate the prevalence, risk factors, diagnostic approaches, treatment strategies, and associated complications of gestational diabetes mellitus (GDM). Methodology: This study employed a cross-sectional observational design conducted in a clinical setting. The population consisted of pregnant women aged 18 and above, attending antenatal clinics in healthcare facilities. A total of 300 participants were selected using purposive sampling. The inclusion criteria included pregnant women between 24 and 28 weeks of gestation with no prior history of type 1 or type 2 diabetes. Data were collected through structured interviews, medical record reviews, and laboratory tests, including blood glucose measurements and oral glucose tolerance tests. Descriptive and inferential statistical methods were used for data analysis. Results: The study found that the prevalence of gestational diabetes was higher in women over the age of 35, women with obesity, and those with a family history of diabetes. Ethnic disparities were observed, with Hispanic women showing the highest prevalence of GDM. Insulin therapy was identified as the most effective treatment, with 90% of women achieving blood glucose control. Lifestyle interventions, such as diet control and exercise, were also beneficial, although slightly less effective than insulin therapy. The study also identified common complications of GDM, including macrosomia, neonatal hypoglycaemia, and an increased likelihood of caesarean sections. Conclusion: The study concluded that gestational diabetes is a significant health concern with profound implications for both maternal and fetal health. Early screening, targeted interventions, and a multidisciplinary approach to treatment are crucial in managing the condition and preventing complications. The findings underscore the importance of addressing risk factors such as obesity, age, and ethnicity in the prevention and management of GDM. Further research is needed to explore the long-term outcomes for both mothers and their children.