Relationship Between Serum Luteinizing Hormone Levels With The Ovarian Response And Pregnancy Outcomes In Vitro Fertilization-Embryo Transfer

Objective By detecting serum LH levels in patients at different points in the IVF/ICSI-ET treatment cycle,we investigated the relationship between serum LH and its trend with ovarian response and pregnancy outcome,and then provided a theoretical basis for improving the clinical pregnancy rate and cumulative pregnancy rate in IVF/ICSI-ET.Methods 664 infertility patients who underwent IVF/ICSI-ET for pregnancy at Reproductive Medicine Center of the Genaral Hospital of Ningxia Medical University from 2018.09 to 2022.09were collected.According to the basal LH levels from low to high,they were divided into three groups:group A1（first 25%of the interval,166 cases）,group A2（25%～75%of the interval,332cases）,and group A3（second 25%of the interval,166 cases）;Three groups were divided according to LH on the day of Gn initiation:group B1,group B2,and group B3（same method as above）;Three groups according to LH on the day of HCG injection:group C1,group C2,and group C3（same method as above）;The patients were divided into two groups according to the change of LH on the day of HCG injection and on the day of Gn initiation:elevated trend group（377 cases）and decreased trend group（287 cases）;According to the pregnancy outcome,they were divided into two groups:pregnancy group（205 cases）and non-pregnancy group（227 cases）.Ovarian reserve function,ovarian response,laboratory indices,pregnancy and obstetric outcomes were compared in each group separately.Using SPSS 26.0 statistical software,the measurement data were expressed as±s,the F test was used for comparison among the three groups,and the t test was used for comparison between two groups;the count data were described as%,and theX²test was used for comparison between groups.P<0.05 was considered a statistically significant difference.Results（1）The serum AMH and b LH levels and the number of AFC in group A1 were observably lower than those in groups A2 and A3（all P<0.001）,while the follicular output rate and the b FSH/b LH ratio in group A1 were significantly higher than those in groups A2 and A3（all P<0.001）.（2）The number of follicles with follicle diameter≥14/16/18mm on the day of HCG injection was significantly higher in group B3 than in groups B1 and B2（P<0.001,P<0.05,P<0.05,respectively）,but the blastocyst formation rate was notably lower in group B3 than in groups B1 and B2（P<0.01）.（3）The number of follicles with follicle diameter≥14/16/18mm on the day of HCG injection in the C3 group was memorably higher than those in the C1 and C2groups（P<0.001,P<0.01,P<0.01,respectively）,but the blastocyst formation rate in the C3 group was lower than that in the C1 and C2 groups（P<0.01）.（4）The E₂level on the HCG injection day and early miscarriage rate（3.83%vs 9.14%）were significantly lower in the elevated trend group than in the decreased trend group（P<0.01,P<0.05,respectively）,while the blastocyst formation and carrying rate（31.91%vs 21.32%）were higher than in the decreased trend group（both P<0.05）,and the clinical pregnancy rate（51.49%vs.42.64%,P=0.067）was also higher.（5）Endometrial thickness on the day of transfer was significantly higher in the pregnant group than in the non-pregnant group（P<0.01）.Conclusion（1）Serum basal LH levels and follicular output rate were helpful to assess ovarian reserve function,while follicular output rate could also predict ovarian response.（2）High LH levels in the controlled ovarian hyperstimulation cycles could attain more mature follicles but result in lower blastocyst formation rate.（3）Those with elevated LH levels on the day of HCG injection compared with those on the day of Gn initiation had lower E₂levels and miscarriage rates,for them,controlled ovarian hyperstimulation was relatively safer and they had a better pregnancy outcomes.（4）The trend of rise or fall of serum LH level during the controlled ovarian hyperstimulation cycles can be used as one of the indicators to predict pregnancy outcome in IVF/ICSI-ET.