Additional luteal support might improve IVF outcomes in patients with low progesterone level in middle luteal phase following a GnRH agonist protocol.

AIM: The purpose of the study was to explore the efficacy of additional luteal support (ALS) for patients with low progesterone (P4) level in the middle luteal phase. METHODS: A retrospective study of 1401 women who underwent their first in vitro fertilization (IVF) treatment with a GnRH agonist protocol was analyzed. Patients were divided into five groups according to P4 level in the middle luteal phase (group I>40ng/mL, group II 31-40 ng/mL, group III 21-30 ng/mL, group IV 11-20 ng/mL and group V 0-10 ng/mL. Besides routine luteal support, the group V was offered with additional oral dydrogesterone 10 mg twice daily to HCG test (ALS group). RESULTS: After a multiple regression analysis, a similar higher hCG positive rate, clinic pregnancy rate and lower early pregnancy loss rate were achieved in group I and group V. In contrast to group I, group IV demonstrated significant lower HCG positive rate (OR = 0.65 [0.43; 0.99], p = .05), lower clinic pregnancy rate (OR = 0.60 [0.41; 0.88], p < .01) and significant higher early pregnancy loss rate (OR = 1.80 [1.08; 2.99], p = .02). The group III also resulted in significant lower clinic pregnancy rate (OR = 0.56 [0.36; 0.87], p = .01). The live birth rate tended to be higher in group I and group V but without a significant difference. CONCLUSION: Following agonist protocol, additional luteal support might improve IVF outcomes in patients with low serum P4 level in the middle luteal phase.

A novel modified ultra-long agonist protocol improves the outcome of high body mass index women with polycystic ovary syndrome undergoing IVF/ICSI.

In an attempt to evaluate the effectiveness of a novel modified ultra-long agonist (ULA) protocol on polycystic ovary syndrome (PCOS) patients undergoing in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI), a retrospective study of 499 women employed with either ULA or conventional long agonist (LA) protocol was analyzed. In high BMI group (>25 kg/m²), the ULA protocol yielded significant higher clinic pregnancy rate (PR) (70.2% versus 50.8%, p < 0.05), implantation rate (52.7% versus 35.7%, p < 0.05) and live birth rate (63.8% versus 39.0%, p < 0.05) when compared with LA protocol. In low BMI group (≤25 kg/m²), the ULA protocol also demonstrated a higher clinic PR (70.8% versus 59.5%, p < 0.05) whereas implantation rate and live birth rate are comparable. Within ULA protocol, the clinic PR, implantation rate and live birth rate are similar between high and low BMI patients. Similarly, the clinic PR and live birth rate demonstrated no significant difference within LA group but there is a significant lower implantation rate (35.7% versus 63.9%, p < 0.05) observed in high BMI patients. No difference in miscarriage rate and severe OHSS rate was found among all groups. In conclusion, ULA protocol benefits the IVF outcomes of PCOS patients with high BMI status.

[Establishment of a long-term culture system for mouse spermatogonial stem cells in vitro].

OBJECTIVE: To establish a long-term proliferation culture system for mouse spermatogonial stem cells. METHODS: Testis tissues were obtained from 30 newborn male ICR mice on postnatal day 2-6. Testis cell suspension was collected by two-step enzymatic digestion prior to culture. The dissociated cells were aliquoted into tissue culture plates and cultivated with a modified system composed of serum-free defined medium on mouse embryonic fibroblasts (MEF) feeders. Their proliferation was determined by the BrdU incorporation test and the cultured cells identified by alkaline phosphatase (AP) activity, immunofluorescence staining and RT-PCR assay. RESULTS: The cultures remained in a steady state and continued to generate germ cell colonies. The undifferentiated state was confirmed by strong positivity for AP activity, immunofluorescent staining of GFRalpha-1+ /Oct-4+ /VASA+ /SCP3- and GFRalpha-1+ /Oct-4+/SCP3- at the gene expression levels. CONCLUSION: Mouse spermatogonial stem cells could be expanded in our defined culture system and passaged steadily in vitro. The harvested cells remained in an undifferentiated state, which has provided a good platform for the study of spermatogenesis in vitro.

Stem cell factor affects fate determination of human gonocytes in vitro.

The stem cell factor (SCF), binding its tyrosine kinase receptor c-Kit, has been shown to play essential roles in the proliferation, differentiation, and survival of germline cells. However, few reports are available about the effect of SCF on the development of human gonocytes within the fetal testis. The objective of this study was to investigate whether SCF affects the biological behaviors of human gonocytes before or after they enter the mitotic arrest stage. Employing an organ culture system, we observed that addition of exogenous SCF could influence the morphology of human gonocytes in vitro. Moreover, SCF was able to trigger the colony formation of round gonocytes, which were characterized positive for alkaline phosphatase activity, Oct-4, SSEA-4, and c-Kit as well. We found that SCF exerted actions in a dose- and age-dependent manner, although the stimulatory effect lasted no more than 14 days. We also showed that SCF played a role in suppressing the apoptosis of human gonocytes. Blocking of SCF signaling with either phosphatidylinositol 3-kinase or mitogen-activated protein kinase inhibitor resulted in similar apoptotic features as well as the SCF-withdrawal cultures. Taken together, we report that SCF acts as a potent regulator in the fate determination of human gonocytes. Our studies should form the basis for in vitro studies and facilitate investigation of the molecular mechanisms underlying this unique stage.