Abstract: Objective：To study the ovarian response and IVF/ICSI-ET outcome of the long GnRH-a protocol in those patients with base LH＜2 IU/L, so as to explore the correlation of LH as a single index and ovarian reserve. Methods：Those patients undergoing IVF/ICSI-ET with the base FSH＜10 IU/L from January 2014 to March 2017 were enrolled. According to the age and the base LH level, those patients were divided into four groups, the group A: age ≤35 years [25～35 years old, the average age (28.86±3.10)] and base LH＜2 IU/L (n=88); the group B: age ≤35 years [25～35 years old, the average age (28.48±3.72)] and base LH 2～5 IU/L (n=226); the group C: age ＞35 years [36～42 years old, the average age (38.54±2.84)] and base LH＜2 IU/L (n=24); the group D: age ＞35 years[36～42 years old, the average age (37.64±2.40)] and base LH 2～5 IU/L (n=58). The superovulation rate, the quantity and quality of embryo, and the pregnancy rate were compared. Results：The base LH level and LH levels on the down-regulated day and Gn starting day in the group A were significantly lower than those in the group B (P＜0.05), while the total dose of Gn in the group A was higher than the group B (However, P＞0.05). The E2 level on the day of hCG injection, the number of ≥14 mm follicles, the retrieved oocyte number, the number of 2PN and the number of high quality embryos in the group A were significantly lower than those in the group B (all P＜0.05). The FSH/LH ratio in the group A was 4.06. The base LH level and LH levels on the down-regulated day and Gn starting day in the group C were significantly lower than those in the group D (P＜0.05), while the total dose of Gn in the group C was higher (However, P＞0.05). There were no significant differences in the E2 level on the day of hCG injection, the number of ≥14 mm follicles, the retrieved oocyte number, the number of 2PN and the number of high quality between the group A and group B (all P＞0.05). The FSH/LH ratio in the group C was 4.23. Interestingly, there were no significantly differences in the LH level on the day of hCG injection, the rate of biochemical pregnancy and the rate of clinical pregnancy between the group A and group B, or between the group C and group D (both P＞0.05). Conclusions：The age ≤35 and base LH＜2 IU/L, as two parameters of ovarian reserve function, can be used as clinical references of ovarian stimulation protocols.
【Keywords】  

Key words: Superovulation, Follicle stimulating hormone, Luteinizing hormone, Estrogens, Fertilization in vitro, Embryo transfer