Background: The endometrial thickness is an important determinant for the successful implantation and pregnancy. This research was aimed to evaluate relationship between the endometrial thickness with serum estradiol and progesterone levels in patients visited in Ob&Gyn clinic of Shahid Sadoughi hospital.

Material and Methods: Enrolled in the study were 440 patients visited in Ob&Gyn clinic of Shahid Sadoughi hospital between Jan. 2011 to Sep. 2012. Only patients with regular menstrual cycle were included in study. Patients with myoma, adenomyosis, endometrial polyps or other uterine anomaly, those who smoked, women with BMI greater than 30 and who were taking medications that could affect endometrial thickness were excluded. Endometrial thickness one day before and 5-7 days after ovulation was measured by using trans-vaginal ultrasonography. Also, serum estradiol and progesterone levels were measured in 5-7 days after ovulation. Data analysis was done through SPSS version 16 with using descriptive statistics and ANOVA.

Results: The mean age of patients was 27.37±4.44. Endometrial thicknesses were 9.80±0.80 and 10.13±1. one day before and 5-7 days after ovulution, respectively. 5% of patients had thin endometrium (<7 mm) in two measurements. Serum estradiol and progesterone levels were respectively 169.88±17.64 pg/ml and 7.32±6.93 mg/ml. There were no significant association between endometrial thickness and age, and also endometrial thickness and progesterone level. The same relation between endometrial thickness and estradiol serum level was observed only in age group of <20 years. (P=0.000)

Conclusion: The results showed that serum stradiol and progesterone levels can not be the determinants of endometrial thickness in women.