Objective:To evaluate the cumulative live birth rate (CLBR) of mild stimulation and conventional stimulation in Poseidon 4 group for progestin-primed ovarian stimulation protocols (PPOS).Methods:It was a single-center, retrospective cohort study. The study included the first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles in the Reproductive Center of the Third Affiliated Hospital of Zhengzhou University from January 2017 to March 2020, and included patients met the criteria of Poseidon 4 group and accepted PPOS. According to the different starting dosage of gonadotropin (Gn), it was divided into mild stimulation group and conventional stimulation group. In mild stimulation group, Gn starting dosage was 150 U, and in conventional stimulation group Gn starting dosage was 300 U. The primary outcome measure was CLBR. Secondary observation indicators were No. of oocytes retrieved, No. of two pronuclei (2PN), No. of available embryos, No. of high-quality embryos and cumulative pregnancy rate. Results:A total of 1 334 cycles met the inclusion and exclusion criteria. After 1∶3 propensity score matching (PSM) model, 116 cycles of mild stimulation and 348 cycles of conventional stimulation were included for analysis. The total dosage of Gn used in the conventional ovarian stimulation group was significantly higher than that in the mild stimulation group [2 700.00 (2 400.00, 3 300.00) U vs. 1 500.00 (918.75, 2 456.25) U, P<0.001]. The number of oocytes retrieved [3.00 (2.00, 4.00)], 2PN [2.00 (1.00, 3.00)], available embryos [1.00 (1.00, 2.00)] and high-quality embryos [1.00 (0.00, 1.00)] in the conventional stimulation group were significantly higher than those in the mild stimulation group [2.00 (1.00, 3.00), P<0.001; 1.00 (1.00, 2.00), P=0.002; 1.00 (0.00,2.00), P=0.002; 0.00 (0.00, 1.00), P=0.025]. There was no statistical difference in the cumulative pregnancy rate between mild stimulation and conventional stimulation [15.52% (18/116) vs. 19.54% (68/348), P=0.334]. The CLBR of the mild stimulation group was 11.21% (13/116), and the CLBR of the conventional stimulation group was 14.08% (49/348), with no significant difference between the two groups ( P=0.431). Conclusion:Conventional stimulation increased the dosage of Gn used, and the number of oocytes retrieved and available embryos were more than those in mild stimulation, but the CLBR was similar between the two protocols. Therefore, mild stimulation is also an important clinical option for patients with low ovarian prognosis.

Objective:To evaluate the cumulative live birth rate (CLBR) of mild stimulation and conventional stimulation in Poseidon 4 group for progestin-primed ovarian stimulation protocols (PPOS).Methods:It was a single-center, retrospective cohort study. The study included the first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles in the Reproductive Center of the Third Affiliated Hospital of Zhengzhou University from January 2017 to March 2020, and included patients met the criteria of Poseidon 4 group and accepted PPOS. According to the different starting dosage of gonadotropin (Gn), it was divided into mild stimulation group and conventional stimulation group. In mild stimulation group, Gn starting dosage was 150 U, and in conventional stimulation group Gn starting dosage was 300 U. The primary outcome measure was CLBR. Secondary observation indicators were No. of oocytes retrieved, No. of two pronuclei (2PN), No. of available embryos, No. of high-quality embryos and cumulative pregnancy rate. Results:A total of 1 334 cycles met the inclusion and exclusion criteria. After 1∶3 propensity score matching (PSM) model, 116 cycles of mild stimulation and 348 cycles of conventional stimulation were included for analysis. The total dosage of Gn used in the conventional ovarian stimulation group was significantly higher than that in the mild stimulation group [2 700.00 (2 400.00, 3 300.00) U vs. 1 500.00 (918.75, 2 456.25) U, P<0.001]. The number of oocytes retrieved [3.00 (2.00, 4.00)], 2PN [2.00 (1.00, 3.00)], available embryos [1.00 (1.00, 2.00)] and high-quality embryos [1.00 (0.00, 1.00)] in the conventional stimulation group were significantly higher than those in the mild stimulation group [2.00 (1.00, 3.00), P<0.001; 1.00 (1.00, 2.00), P=0.002; 1.00 (0.00,2.00), P=0.002; 0.00 (0.00, 1.00), P=0.025]. There was no statistical difference in the cumulative pregnancy rate between mild stimulation and conventional stimulation [15.52% (18/116) vs. 19.54% (68/348), P=0.334]. The CLBR of the mild stimulation group was 11.21% (13/116), and the CLBR of the conventional stimulation group was 14.08% (49/348), with no significant difference between the two groups ( P=0.431). Conclusion:Conventional stimulation increased the dosage of Gn used, and the number of oocytes retrieved and available embryos were more than those in mild stimulation, but the CLBR was similar between the two protocols. Therefore, mild stimulation is also an important clinical option for patients with low ovarian prognosis.