Introduction: Hypertension complication during the pregnancy will lead to morbidity and fatality in pregnancy. Objective: The study was done to identify the differences of calculated creatinine clearance level between two groups of pregnant patients which were gestational and chronic hypertension patients from pregnancy to the postpartum period. Methods: A prospective cohort study was done from September 2015 to April 2016 on the Obstetrics __ampersandsignamp; Gynaecology Clinic of Hospital USM patients. A total of 10 pregnant mothers from gestational hypertension patients and 10 pregnant mothers from chronic hypertension patients who signed the consent form were included in the study. The patient__ampersandsignrsquo;s medical records were re-viewed. Patients with proteinuria __ampersandsigngt; 300mmHg, preeclampsia or eclampsia, on Angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs), and those who have present or history of diabetes, renal disease, liver disease, systemic lupus erythematosus, hepatitis, hyperaldosteronism, renal artery stenosis or thyrotoxicosis were excluded from the study. Blood for renal function test was collected at three phases. The collection was at the last trimester of pregnancy followed by six weeks and 12 weeks after labour. Repeated measure ANOVA was used to analyze the pattern of the calculated creatinine clearance between the groups from pregnancy to postpartum. Results: The pattern of calculated creatinine clearance is the difference between groups. In the gestational hypertension group, the calculated creatinine clearance was an increase from 6 weeks postpartum to 12 weeks. The pattern of calculated creatinine clearance still declined in the chronic hypertension group after 6 weeks postpartum. Conclusion: The women with previous hypertensive disorders during pregnancy should have a regular checkup especially on checking renal function test as it is one of the major causes of unintended of having renal disease.