BACKGROUND
In recent years, infertility, which affects human development and health, has become a global medical and sociological problem. Assisted reproductive technologies have been developed for more than 40 years. In recent decades, assisted reproduction techniques have evolved. However, even when good quality embryos are selected for transfer to the uterus, the implantation rate remains low.
OBJECTIVE
The aim of this study was to investigate whether the FSH (follicle-stimulating hormone) / LH (Luteinizing hormone) ratio correlates with ovarian response in a cross-sectional retrospective study of a population with normal levels of anti-Müllerian hormone (AMH) .
METHODS
This was a retrospective cross‐sectional study with data obtained from medical records from March 2019 to December 2019 at the reproductive center in the Affiliated Hospital of Southwest Medical University. The relationship between FSH/LH and ovarian response was analyzed using smoothed curve fitting to find the threshold or saturation point for the population with mean AMH level (1.1<AMH<6μg/L). The enrolled cases were divided into two groups according to AMH threshold or saturation. Cycle characteristics, cycle information and cycle outcomes were compared. The increase in FSH/LH with the relationship between low ovarian responses and cycle outcomes was analyzed among the two groups.
RESULTS
A total of 428 patients who met the inclusion criteria were enrolled in this study. The median age of the patients was 31 years and the median duration of infertility was 3 years. The median AMH and AFC were 4.06ug/L and 8, respectively. The clinical pregnancy rate in this study was 28%. OSI and age (rs=- 0.115, p=0.017), FSH (rs=- 0.267, p < 0.001), FSH/LH (rs=- 0.203, p < 0.001), total Gn dose (rs=- 0.551, p < 0.001), total Gn days (rs=- 0.319, p= 0.004), transferred embryos ( rs=- 0.037, p=0.448), LH level on HCG day (rs=-0.041, p= 0.397), and p level on HCG day (rs=- 0.134, p= 0.006) were significantly and negatively correlated. OSI was also significantly and positively correlated with AMH (rs=0.340, P<0.001), AFC (rs=0.223, P<0.001), retrieved oocytes (rs=0.789, P<0.001) and MII eggs (rs=0.099, P=0.040). The OSI value decreases with the FSH/LH level increase found by a smoothed curve in the group with AMH<1.1ug/L. Analysis of the threshold and saturation levels yielded an optimal saturation point of 2.3. Age, BMI, AFC, AMH, FSH, LH, E2, Gn total dose, and retrieved oocytes were statistically significant. Age, BMI, FSH, and total Gn dose were significantly higher in the FSH/LH＞3.group than in the FSH/LH < 3.5 group(P＜0.05). AFC, AMH, LH, and E2 were significantly lower in the FSH/LH＞3.5 group than in the FSH/LH<3.5 group (P＜0.05). The retrieved oocytes, MII eggs, E2, and P on HCG day were lower than those in the FSH/LH<3 group (P<0.05).
CONCLUSIONS
We conclude that increased FSH/LH in the AMH normal group reduces the ovarian response to exogenous Gn. Meanwhile, FSH/LH of 3.5 was found to be a useful diagnostic threshold for assessing ovarian response in people with normal AMH levels. Ovarian sensitivity index (OSI) can be used as an indicator of ovarian response in assisted reproductive technology (ART) treatment.