Abstract
OBJECTIVES: To compare the pregnancy outcomes of luteal phase and follicular phase progestin-primed ovarian stimulation protocol with clomiphene citrate supplementation (LPPOS+CC and FPPOS+CC) in young women with diminished ovarian reserve (DOR). METHODS: A total of 483 women aged ≤35 years with DOR, who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI)/embryo transfer (ET) with controlled ovarian stimulation using LPPOS+CC (n=257) or FPPOS+CC (n=226) protocols during June 2018 and December 2021 at the First Affiliated Hospital of Wenzhou Medical University, were included in this retrospective study. The baseline characteristics, superovulation results, laboratory related indicators between the two groups, and the pregnancy outcomes of women who achieved at least one high-quality cleavage-stage embryo or good-morphology blastocyst were compared between the two groups. RESULTS: No statistically significant differences were identified between the groups with respect to age, duration of infertility, proportion of secondary infertility, previous failed cycles, body mass index, anti-Müllerian hormone, antral follicle count, basal luteinizing hormone level, basal progesterone level, number of oocytes retrieved, oocyte maturation rate, high-quality cleavage-stage embryo cycle rate, the percentage of women with profound pituitary suppression, live birth rate and preterm birth rate (all P>0.05). The LH levels on the day of trigger [4.0 (2.7, 5.3) vs. 5.1 (3.2, 7.2) IU/L], the percentage of women with LH levels of >10 IU/L on the trigger day (3.13% vs. 10.67%), and the two pronucleus (2PN) rate of ICSI oocytes (72.16% vs. 79.56%) were significantly lower in the LPPOS+CC group than those in the FPPOS+CC group (P<0.05 or P<0.01). The duration of stimulation [11 (9, 12) vs. 9 (8, 11) d], the consumption of total gonadotropin [2213 (1650, 2700) vs. 2000 (1575, 2325) IU], the progesterone levels on the day of trigger [1.3 (0.8, 2.9) vs. 0.9 (0.6, 1.2) ng/mL], the clinical pregnancy rate [61.88% vs. 46.84%], and implantation rate [42.20% vs. 31.07%] in the LPPOS+CC group were significantly higher than those in the FPPOS+CC group (all P<0.01). CONCLUSIONS: Compared to FPPOS+CC, the LPPOS+CC protocol appears to have better pregnancy outcomes for young women with DOR undergoing IVF/ICSI-ET.