Effects of three-area laser-assisted zona thinning in 8-cell human embryos on pregnancy outcomes in vitro fertilization / 대한생식의학회지

OBJECTIVE: This study conducted a preliminary examination of the effects of three-area laser-assisted zona thinning (LAZT) during the cleavage stage of embryo development on the hatching process in human in vitro fertilization-embryo transfer (IVF-ET) with subjects of advanced female age or frozen-thawed (FT) embryos. METHODS: Eight-cell stage embryos were treated with LAZT in three areas of the zona pellucida at 120° intervals. The control group was embryos without LAZT. Of the 72 consecutive fresh cycles and the 28 FT embryo transfer cycles, the patients in 55 fresh cycles and 17 FT cycles declined LAZT, and those cycles were defined as the control group. RESULTS: In the fresh cycles, the pregnancy rates were similar in the LAZT and control groups. However, in the FT cycles, the pregnancy rate was significantly higher in the LAZT group than in the control group (45.5% in the LAZT group vs. 23.5% in the control group, p < 0.05). CONCLUSION: These results show that multi-area LAZT resulted in significantly improved pregnancy outcomes in human 8-cell embryos compared to controls.

Vitrification solution without sucrose for cryopreservation in mouse blastocysts / 대한생식의학회지

OBJECTIVE: This study was designed to investigate the survival rate of vitrified mouse blastocysts depending on the presence or absence of sucrose in vitrification solution. METHODS: Mouse two-cell embryos were collected and cultured to blastocysts. Two vitrification solutions were prepared. The control solution was composed of 25% glycerol, 25% ethylene glycol, and 0.5 M sucrose (G25E250.5S) containing 2.5 mL glycerol, 2.5 mL ethylene glycol, 2 mL SSS, and 0.855 g sucrose in 5 mL PB1. The experimental solution was composed of 25% glycerol and 25% ethylene glycol (G25E25) and contained 2.5 mL glycerol and 2.5 mL ethylene glycol in 5 mL PB1. Artificial shrinkage was conducted by aspirating the blastocoelic fluid using an ICSI pipette. To examine the effect of sucrose in the vitrification solution on the survival rate of mouse blastocysts, the shrunken-equilibrated blastocysts were rehydrated or vitrified after being exposed to one of the two vitrification solutions. After exposure and the vitrification-thawing process, the re-expansion rate and hatching rate were evaluated after 6 hours of in vitro culture. RESULTS: The re-expansion rate of mouse blastocysts exposed to vitrification solution with and without sucrose were not different in the experimental solution (without sucrose) (98%) and the control solution (with sucrose) (92%) (p>0.05). The hatching rate was higher in the experimental solution (95%) than in the control solution (88%), but did not differ across two treatments (p>0.05). The re-expansion rate of mouse blastocysts vitrified in the control solution was 92% and 94%, respectively (p>0.05), and the hatching rate was higher in the experimental solution (90%) than in the control solution (74%) (p<0.05). CONCLUSION: Sucrose need not be added in vitrification solution for freezing of artificially shrunken mouse blastocysts.

Clinical Characteristics of Breast Cancer Detected during Hormone Therapy in Korean Women / 대한폐경학회지

OBJECTIVES: This study was performed to assess the risk factors, histologic and clinical features of breast cancer in postmenopausal women receiving hormone therapy (HT). METHODS: We evaluated 40 breast cancer patients who received HT due to postmenopausal symptoms by reviewing their medical charts at Pusan National University Hospital. Research variables, including patients' history, type and duration of received HT, moment of cancer debut after starting HT, radiological characteristics of breast cancer stage, histologic type, tumor size, grade, lymph node metastasis, estrogen and progesterone receptor status and 5-year survival were investigated. RESULTS: In the risk factors of breast cancer patients, only one patient had familial history of breast cancer. No patient had smoking history. The average body mass index (BMI) was 23.2 kg/m2. Twelve patients (30%) had estrogen only therapy, 13 patients (32.5%) had combined estrogen and progesterone therapy, 10 patients (25%) had tibolone therapy and the others consecutively received combination therapy of the above regimens. The mean duration of treatment was 31 +/- 27.9 months (range 0.4-115 months). In the distribution of the cancer debut after starting HT, in 4 cases (10%) was within 1 year, 5 cases (12.5%) within 1-2 years, 10 cases (25%) within 2-3 years, 4 cases (10%) within 3-4 years, 1 case (2.5%) within 4-5 years, and 16 cases (40%) within more than 5 years. The average diameter of tumor size was 1.7 cm. In 92.5% of cases, the tumor was of ductal type. Tumor stage 0 and 1 appeared in 66% and grade I was present in 38% of investigated cases. Hormone receptor-positive breast cancers were 85% and 70% of patients had negative lymph node metastases. The 5-year survival rate was 92%. CONCLUSION: The breast cancers which emerged during HT in postmenopausal women had hormone receptor-positive tendency. The size and stage of these breast cancers were shown as small and low, and represented low-grade differentiation. Recurrences of disease were uncommon and we found favorable 5-year survival rates and good prognosis.