Serum Estradiol Levels During Controlled Ovarian Hyperstimulation among in Vitro Fertilized Women in Gaza Strip

Abstract

Background: Estradiol (E2) is the second predominant steroid sex hormone produced mainly by the ovary, placenta, and in smaller amounts by the adrenal cortex. There are two peaks of secretion: one just before ovulation and one during the mid-luteal phase. Estrogens facilitate the growth of the ovarian follicles and increase the motility of the uterine tubes. Currently, controlled ovarian hyperstimulation (COH) is monitored by serum E2 levels which are believed to primarily detect functional activity of follicles. Objective: To assess serum estradiol levels during COH in vitro fertilization (IVF) women from Gaza Strip. Methods: This is a prospective descriptive study. A meeting interview was used for filling in the questionnaire. E2 was determined by using enzyme linked immunosorbent assay in 75 women undergoing IVF at Al-Basma Fertility Center in Gaza City. The number of oocytes and embryos were recorded for each female and the occurrence of pregnancy was followed for three months. Obtained data were computer analyzed using SPSS statistical package version 18. Results: The mean age of the study population was 29.2±5.9 years. Questionnaire interview showed that the cause of infertility was mostly referred to husbands. More than half of women seeking IVF had no children and had repeated IVF. The mean E2 level before IVF program was 35.5 pg/ml. However, during IVF program, E2 level increased markedly registering a value of (1889 pg/ml). The highest level of E2 (2194.4 pg/ml) during IVF program was recorded at age group 26-35 years. The number of total retrieved oocytes was significantly decreased with increasing age with means of 10.95±3.83, 9.33±5.66 and 5.77±5.57, at age groups ≤25, 26-35 and >35 years, respectively (F=3.932 and p=0.024). The ovarian response was better with age 26.7±5.02 compared to other age groups (9-16 oocytes, F=6.773 and p=0.001). The mean number of mature oocytes increased in the different responders as: 2.0±0.8, 5.9±1.5, 8.2±2.4 and 13.4±3.7 in poor, normal, good and high responders, respectively (F=61.065 and p=0.000). When related to age, IVF outcome showed that the chance of IVF success increased with decreased age (positive pregnancy at 26.7±4.1 years, F=4.278 and p= 0.018). The maximum number of total and mature oocytes was recorded in women who achieved positive pregnancies (11.5±5.3 and 8.4±3.8 oocytes, respectively, P=0.004). The mean age (27.8±4.9 years), the numbers of total and mature oocytes, and embryo were significantly increased with increased levels of E2, showing a good response at E2 level=1000-2000 pg/ml. Correlation coefficient revealed that the number of mature oocytes showed significant negative and positive correlations with age and number of embryo, respectively (r=-0.276, p=0.017 and r=0.890, P=0.000). Conclusion: At E2 level 1000-2000 pg/ml and a mean age of 27.8±4.9 years, good ovarian response, number of embryo and high chance of pregnancy could be achieved. Consequently, for women to undergo a more likely successful IFV program, it is recommended to optimize E2 level at 1000-2000 pg/ml.