• 제목/요약/키워드: Sperm maturation

검색결과 193건 처리시간 0.027초

소 미성숙 난포란의 급속동결 융해후 생존성에 관한 연구 (Studies on the Survival Rate of Rapidly Frozen Bovine Immature Oocytes)

  • 김상근;이봉구
    • 한국수정란이식학회지
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    • 제10권2호
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    • pp.115-120
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    • 1995
  • This study was carried out to investigate On in vitro fertilization, survival rate and developmental rate of rapidly frozen bovine immature oocytes. Immature oocytes cultured for 1, 12, 24, 48 hours in 20% FCS + TCM-199 medium and thereafter rapidly freezing-thawed oocytes inseminated with capacitated sperm. The immature oocytes following dehydration by 1.5M DMSO + 2.0M glycerol + 0.25M sucrose + TCM 199 media + 20% FGS were directly plunged into liquid nitrogen and thawes in 3$0^{\circ}C$ water. Rapid freezing embryos co-cultured in 20% FCS + TCM-199 media containing hormones(21U/mL PMSG, 21U /mL hGG and 1 $\mu$g /mL 17$\beta$-estradiol) and cumulus cells(1 x 105-6 cells). Survival rate was defined as development rate on in vitro culture or FDA-test. The results are summarized as follows ; 1. The in vitro maturation and fertilization rate of immature bovine oocytes on in vitro maturation period(1, 12, 24, 48 hrs) before rapid freezing4hawed were 57.1%, 45.7%, 37.1%, 25.7% and 40.0%, 31.4%, 20.0%, 11.4%, respectively. 2. The survival rate of immature bovine oocytes on in vitro maturation period(1, 12, 24, 48 hrs) before rapid freezing-thawed were 33.3%, 26.7%, 20.0%, and 10.0%, respectively. The survival rate of rapid freezing4hawed immature oocytes was significantly lower than that of non-freezing oocytes. 3. The survival rate of rapid freezing4hawed excellent and good bovine embryos co-cultured in 20% FCS + TCM-199 media containing hormones(PMSG, hCG, 17$\beta$-estradiol) and cumulus cells 4 to 5 hrs and 20 to 24 hrs were 35.0%, 15.0% and 25.0%, 15.0% and 40.0%, 20.0% and 30.0%, 15.0%, respectively. The survival rate of embryos co-cultured in TCM-199 media containing hormones and cumulus cells was significantly higher than that of non co-culture.

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A Role of Unsaturated Fatty Acid in Animal Reproductive Cells and Biology

  • Hwangbo, Yong;Kim, Hwa-Young;Lee, Yu-Rim;Lee, Seung Tae;Lee, EunSong;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Reproductive and Developmental Biology
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    • 제40권2호
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    • pp.15-22
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    • 2016
  • As a one of unsaturated fatty acid, polyunsaturated fatty acids (PUFAs) have multiple actions: as precursor of prostaglandins (PGs), steroid hormone synthesis and energy production in animal reproduction. PUFAs, which include omega-3 (n-3) and omega-6 (n-6), are derived from the diet and changed by diet, species, breed and season. The plasma membrane of spermatozoa in mammals contain various PUFAs. These composition of PUFAs regulate the membrane fluidity and cause lipid peroxidation via generation of reactive oxygen species (ROS). Induced lipid peroxidation by ROS decreased viability and motility of spermatozoa, and it is reduced by addition of antioxidant and low concentration of PUFAs. Because oocytes of animal have a high lipid components, process of oocyte maturation and embryo development are influenced by PUFAs. In in vitro study, oocyte maturation, embryo development, intracellular cAMP and MAPK activity were increased by treatment of n-3 ${\alpha}$-linolenic acid (ALA) during maturation, whereas n-6 linoleic acid (LA) negatively influenced. Also, inhibition of fatty acid metabolism in oocyte influenced blastocyst formation of cattle. PGs are synthesized from PUFAs and various PUFAs influence PGs via regulation of PG-endoperoxide synthase (PTGS). Steroid hormone synthesis from cholesterol is regulated by expression of steroid acute regulator (StAR) protein and mRNA. Exogenous n-3 and n-6 PUFAs altered sex hormone in animal through stimulate or inhibit StAR activity. Because PUFAs altered PG and steroid hormone synthesis, follicular development was influenced by PUFAs. This effect of unsaturated fatty acid could provide information for improvement of reproductive ability in animals.

Functional role of Forskolin and PD166285 in the development of denuded mouse oocytes

  • Cao, Hongguo;Bian, Yani;Zhang, Fei;Tang, Yunshu;Li, Caixia;Chen, Jiemei;Zhang, Xiaorong
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권3호
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    • pp.344-353
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    • 2018
  • Objective: cAMP and mature promoting factor (MPF) play critical roles during the maturation of mammalian oocytes. The aim of this study was to produce the offspring from denuded oocytes (DOs) in mice by regulating cAMP and MPF. Methods: In this study, we used DOs at the germinal vesicle (GV) stage in mice and regulated levels of cAMP and MPF in DOs by adding Forskolin and PD166285 during in vitro maturation without follicle stimulating hormone and luteinizing hormone, respectively. Results: Combined use of $50{\mu}M$ Forskolin for 3 h and $2.5{\mu}M$ PD166285 for additional 21 h enhanced the developmental competence of DOs, maturation rate of DOs was $76.71%{\pm}4.11%$, blastocyst rate was $18.33%{\pm}4.44%$ after parthenogenetic activation (PA). The DOs could successfully be fertilized with sperm in vitro, cleavage rate was $17.02%{\pm}5.82%$ and blastocyst rate was $5.65%{\pm}3.10%$. Besides, 2-cell in vitro fertilization embryos from DOs produced 4 normal live offspring (4/34). Conclusion: The results confirmed that the combination of Forskolin and PD166285 can induce DOs to complete meiosis process and produce normal offspring.

비폐쇄성 무정자증 환자에서 고환의 조직병리학적 진단에 따른 체외수정시술 결과의 비교 (Effect of Testicular Histopathology on Pregnancy Outcomes in Non-Obstructive Azoospermia)

  • 박찬우;서주태;박용석;김혜옥;양광문;김진영;궁미경;강인수;송인옥
    • Clinical and Experimental Reproductive Medicine
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    • 제35권4호
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    • pp.293-301
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    • 2008
  • 목 적: 비폐쇄성 무정자증 환자에서 고환의 조직병리학적 진단에 따라 고환조직내 정자채취술 (Testicular sperm extraction, TESE) 후 난자세포질내 정자주입술 (Intracytoplsmic sperm injection, ICSI)의 체외수정시술 결과를 알아보고자 하였다. 연구방법: 비폐쇄성 무정자증으로 고환조직내 정자채취술 후 난자세포질내 정자주입술을 이용하여 배아 이식을 시행한 122주기를 분석하였다. 고환의 조직병리학적 진단에 따라 Germ-cell aplasia (GA, 40주기), Maturation arrest (MA, 32주기) and severe hypospermatogenesis (S-HS, 50주기)로 구분하여 체외수정시술 결과를 비교하였으며, 이들 결과를 난자세포질내 정자주입술을 이용한 폐쇄성 무정자증 환자의 체외수정시술 결과와 비교하였다. 결 과: 고환조직내 정자채취술 후 난자세포질내 정자주입술시 수정율은 각각 58.1% in GA, 42.2% in MA and 48.0% in S-HS로 조직병리학적 진단에 따른 차이는 없었으며, 폐쇄성 무정자증 환자의 72.9%에 비해 유의하게 낮은 수정율을 보였다 (p<0.001). 고환조직내 정자채취술시 채취된 정자 (spermatozoa, 94주기)로 난자세포질내 정자주입술을 시행한 주기의 배아 이식 후 임신율은 각각 22.6% in GA, 29.4% in MA와 26.1% in S-HS이었으며, 출생률은 각각 16.1%, 29.4%와 19.6%로 조직병리학적 진단에 따른 차이는 없었다. 정자세포 (spermatid, 16주기)를 사용하여 난자세포질내 정자주입술을 시행한 주기의 임신율은 각각 0.0% (0/3 주기), 9.1% (1/11주기)와 0.0% (0/2주기)이었으며, 출생률은 각각 0.0%이었다. 정모세포 (spermatocyte, 12주기)를 사용한 주기의 임신율은 각각 0.0% (0/6주기), 0.0% (0/4주기)와 0.0% (0/2주기)이었으며, 출생률도 각각 0.0%이었다. 결 론: 비폐쇄성 무정자증환자의 배아이식을 시행한 주기에서 고환의 조직병리학적 진단에 따른 난자세포질내 정자주입술시 수정율은 차이가 없었으며, 폐쇄성 무정자증 환자에 비해 유의하게 낮은 수정율을 보였다. 비폐쇄성 무정자증환자에서 고환조직내 정자채취술시 정자를 채취하여 난자세포질내 정자주입술을 시행한 주기의 체외수정시술 결과는 고환의 조직병리학적 진단에 따라 차이를 보이지 않는다.

Novel method of histopathological analysis after testicular sperm extraction in patients with nonobstructive and obstructive azoospermia

  • Cito, Gianmartin;Coccia, Maria Elisabetta;Picone, Rita;Nesi, Gabriella;Cocci, Andrea;Dabizzi, Sara;Garaffa, Giulio;Fucci, Rossella;Falcone, Patrizia;Bertocci, Francesco;Santi, Raffaella;Criscuoli, Luciana;Serni, Sergio;Carini, Marco;Natali, Alessandro
    • Clinical and Experimental Reproductive Medicine
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    • 제45권4호
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    • pp.170-176
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    • 2018
  • Objective: To assess whether the "testicular pool" could be used for histological analysis and whether it gave more accurate information than the standard testicular biopsy. Methods: Between January 2017 and March 2018, this single-center prospective study included 60 azoospermic men undergoing conventional bilateral testicular sperm extraction. Six samples were excised from each testicle and transferred to an embryologist. One additional biopsy was randomly taken from each testis for a histological analysis. After processing, the testicular pool was also sent for a histological analysis, which showed normal spermatogenesis (NS), hypospermatogenesis (HYPO), maturation arrest (MA), Sertoli cell-only syndrome (SCOS), and tubular atrophy (TA). Results: Twenty of the 60 patients (33.3%) had obstructive azoospermia (OA), while the remaining 40 (66.6%) had nonobstructive azoospermia. Their mean age was 40.5 years. All patients with OA had previously undergone unsuccessful testicular fine-needle aspiration. Successful sperm retrieval (SSR) occurred in 93.3% of patients. Histological analysis of the testicular biopsy revealed NS in 12 patients (20%), HYPO and TA in 28 patients (46.6%), MA in eight patients (13.3%), and SCOS in 12 patients (20%). The testicular pool analysis showed NS in 12 patients (20%), HYPO and TA in 44 patients (73.3%), MA in four patients (6.6%), and SCOS in no patients. In four patients with MA (6.6% of the total sample) and 12 patients with SCOS (20% of the total sample) according to the standard testicular biopsy, the embryologist found SSR with cryopreservation. Overall, in 44 patients (73.3%), the testicular pool analysis confirmed the histological findings of the standard testicular biopsy. In the 16 cases (26.6%) with a discrepancy between the single-biopsy histological findings and SSR, the testicular pool analysis confirmed the embryological data on SSR. Conclusion: The testicular pool proved to be easily analyzable, practical, manageable, and more accurate for predicting sperm retrieval than standard testicular biopsy.

산소농도 및 Superoxide Dismutase가 돼지 난포란의 체외성숙과 배발달에 미치는 영향 (Effect of Oxygen Concentrations with Superoxide Dismutase on In Vitro Maturation of Porcine Follicular Oocytes and In Vitro Development of Porcine IVM/IVF Embryos)

  • 한만희;이규승
    • 한국수정란이식학회지
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    • 제16권3호
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    • pp.173-182
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    • 2001
  • 본 연구는 돼지 난포란의 체외성숙배양액에 superoxide dismutase(SOD)를 첨가배양하여 체외성숙과 수성이후 배발달에 미치는 영향과 산소농도 및 SOD가 체외생산된 돼지초기수정란치 배발달에 미치는 영향을 규명하고자 실시하였다. 본 연구에서 얻어진 결과를 요약하면 다음과 같다. 1. 돼지 난포란을 체외성숙배양액인 NCSU-23에 SOD를 각각 0, 100,500 및 1,000uni1s/m1 첨가하여 성숙시킨 다음, 체외수정을 실시한 결과, 핵성숙률, 정자침입율, 다정자침입률 및 평균침입정자수는 처리구와 대조구간 유의적(P<0.05)인 차이가 인정되지 않았고, 웅성전핵형성률은 처리구(90.9∼81.2%)보다 오히려 대조구(95.0%)가 유의적으로 높은 결과를 나타냈다(P<0.05). 2. 체외수정 후, 배발달배양액인 NCSU-23에 7일 동안 배양한 결과, 배반포형성률과 총세포수는 처리구가 대조구보다 유의적(P>0.05) 으고 낮은 결과를 나타냈다. 3. 배발달배양액인 NCSU-23에 SOD를 각각 0, 100, 500 및 1,000uni1s/m1을 첨가하고 5% 및 20% 산소조건하에서 7일동안 배발달을 유기한 결과, 배양 7일째 산소조건에 따른 처리구간 배반포형성률 및 총세포수는 유의차가 없었으며, SOD농도별 배반포형성률은 100 units/ml 처리구에서 0, 500 및 1,000uni1s/m1 처리구 보다 유의적으로 높은 배반포형성률을 나타냈으나, 총세포수에서는 처리구(27.6∼37.3개)가 대조구(45.6개)보다 유의적(P<0.05) 로 낮은 결과를 나타내었다. 따라서 NCSU-23배양액에 SOD의 첨가는 돼지난포란의 체외성숙과 초기배발달에 영향을 미치지 않는 것으로 조사되었으며, 5% 및 20% 산소농도에 따른 영향도 없는 것으로 사료된다.

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Effect of Epidermal Growth Factor (EGF) on Meiotic Maturation and Pronuclear Formation of Porcine Oocytes Produced In Vitro

  • Song S. H.;Kim J. G.;Song H. J.;Kumar B. Mohana;Cho S. R.;Choe C. Y.;Choi S. H.;Rho G. J.;Choe S. Y.
    • Reproductive and Developmental Biology
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    • 제29권2호
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    • pp.127-131
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    • 2005
  • The objective of this study was to examine the effect of EGF on meiotic maturation and pronuclear (PN) formation of porcine oocytes. Prepubertal gilt cumulus-oocyte-complexes (COCs) aspirated from $2\~6mm$ follicles of abbatoir ovaries were matured in TCM199 containing 0.1mg/ml cysteine, $0.5{\mu}/ml$ FSH and LH, and EGF (0, 5, 10, 20, 40 ng/ml) for 22 hr at $39^{\circ}C$ in a humidified atmosphere of $5\%$ $CO_2$ in air. They were then cultured for an additional 22hr without hormones. In Experiment 1, to examine the nuclear maturation at 44hr of culture, the expanded cumulus cells were removed by vortexing for 1 min in 3 mg/ml hyaluronidase. The oocytes were fixed in acetic acid: methanol (1:3, v/v) at least for 48 hr and stained with $1\%$ orcein solution for 5 min. Nuclear status was classified as germinal vesicle (GV), germinal vesicle breakdown (GVBD), prophase-metaphase I (PI-MI), and PII-MII under microscope. In Experiment 2, to investigate PN formation, oocytes were fertilized with Percoll-treated freshly ejaculated sperm $(1\times10^5\; cells/ml)$ in mTBM with $0.3\%$ BSA and 2mM caffeine for 5hr, and cultured in NCSU-23 medium with $0.4\%$ BSA. At 6hr of culture, the embryos were fixed in $3.7\%$ formaldehyde for 48hr and stained with 10ug/ml propidium iodide for 30 min. PN status was classified as no or one PN (unfertilized), 2 PN (normal fertilized) and $\geq3$ PN (polyspermy). Differences between groups were analyzed using one-way ANOVA after arc-sine transformation of the proportional data. The rate of oocytes that had reached to PII-MII were significantly (P<0.05) higher in all groups added EGF than that of non-treated group $(67\%)$, but it did not differ among the all added groups $(86\%,\;85\%,\;79\%\;and\;81\%$, in 5, 10, 20 and 40 ng/ml EGF, respectively). No differences on the incidence of 2PN were observed in all treated groups $(25\%,\;30\%,\;33\%,\;29\%\;and\;29\%$, in 0, 5, 10, 20 and 40 ng/ml EGF, respectively), however, in non-treated group, polyspermy tended to be increased ($66\%\;vs\;. 58\%,\;54\%,\;52\%\;and\;55\%$, 0 vs. 5, 10, 20, 40 ng/ml EGF, respectively). These results suggest that EGF can be effectively used as an additive for enhancing oocyte maturation and reducing the incidence of polyspermy in pig.

Growth differentiation factor 9 and cumulus cell supplementation in in vitro maturation culture media enhances the viability of human blastocysts

  • Chatroudi, Mahla Honari;Khalili, Mohammad Ali;Ashourzadeh, Sareh;Anbari, Fatemeh;Shahedi, Abbas;Safari, Somayyeh
    • Clinical and Experimental Reproductive Medicine
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    • 제46권4호
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    • pp.166-172
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    • 2019
  • Objective: In vitro maturation (IVM) of immature oocytes can be useful for some infertile patients. In IVM programs, the rates of embryo formation and pregnancy are low. Therefore, it is essential to recognize the main factors involved in regulating oocyte maturation in vitro. The purpose of this study was to investigate the effects of growth differentiation factor 9 (GDF9) and cumulus cell (CC) supplementation in IVM medium on the rates of embryo formation and viability of human blastocysts. Methods: A total of 80 germinal vesicle oocytes from stimulated cycles underwent an IVM program. The oocytes were divided into four groups, where group I consisted of IVM media only and served as the control, group II consisted of IVM+CCs, group III consisted of IVM+GDF9 (200 ng/mL), and group IV consisted of IVM+CCs+GDF9 (200 ng/mL). Intracytoplasmic sperm injection was performed on the IVM oocytes, and the cleavage embryos that were generated were vitrified. Following thawing, the embryos were cultured for 3 additional days, and the viability rates of the developed blastocysts were determined. Results: The maturation rate of the oocytes did not differ significantly across the four groups. The fertilization rate in group II was significantly higher than that in the control group (76.5% vs. 46.2%). Embryo formation was significantly more frequent in all experimental groups than in the control group, while blastocyst formation did not show significant differences in the three experimental groups compared to the control. The mean viability rates in groups II, III, and IV were 58.16%, 55.91%, and 55.95%, respectively, versus 37.78% in the control group (p< 0.05). Conclusion: Supplementation of IVM culture media with GDF9 and CCs enhanced the fertilization, embryo formation, and viability rates of blastocysts generated from vitrified cleavage embryos.

인간양수에 의한 생쥐 난자 투명대의 정자수용능력 억제의 관찰 (Human Amniotic Fluid Induces Spontaneous Hardening of the Zona Pellucida of Mouse Immature Oocytes During Maturation In Vitro)

  • 박기상;이택후;송해범;전상식
    • Clinical and Experimental Reproductive Medicine
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    • 제27권1호
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    • pp.23-29
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    • 2000
  • Objective: Zona pellucida (ZP) has been thought to be the barrier of egg to sperm penetration before and after fertilization. The phenomenon of ZP hardening has been considered as a post-fertilization event until now, and it is generally accepted that it is caused by the secretory products of cortical granules released during the cortical reaction. Hardening of ZP could occur "spontaneously" in mammalian oocytes in standard culture conditions, and that it is probably not a consequence of cortical reaction. The purpose of our study was to investigate the effect of human amniotic fluid (HAF) on nuclear maturation (NM) and fertilization ability of mouse immature oocytes. Methods: HAF was obtained from patients undergoing amniocentesis at $16{\sim}20$ weeks of gestation. HAF from five to ten patients was centrifuged and the supernatants was pooled. Cumulusenclosed mouse immature oocytes were incubated in the medium containing HAF, and examined to confirm NM and fertilization. Female ICR mice (about 3 weeks old) were stimulated with 7.5 IU PMSG. Immature oocytes were isolated at $48{\sim}52$ hrs post PMSG injection and cultured in TCM-199 supplemented with 20% HAF for 18 hrs. FBS was used as a control for the examination. Matured oocytes (MII) were fertilized with sperms collected from the epididymis of male mice (over 10 weeks old). Fertilization was in conducted T6 medium containing 15 mg/ml BSA, and confirmed at 6 hrs post-insemination. Fertilization rate was assessed in zona-intact or zona-free oocytes (denuded by trypsin). Evaluation of NM and fertilization was carried out by rapid staining method. ZP hardening was evaluated by incubating cumulus cell-free mature oocytes in 0.001% chymotrypsin at $37^{\circ}C$ for 10 min. Results: There was no significant difference between the effects of HAF (86.6%) and FBS (87.7%) supplements on NM of immature oocytes. When maturation medium was supplemented with HAF, total fertilization rates (7%) were significantly lower (p<0.01) than that of FBS (85.1%). In HAF group, fertilization rate was increased (p<0.01) in zona-free oocytes (7% versus 100%). The resistance of mouse oocyte ZP to digestion by chymotrypsin after maturation in vitro was significantly higher (p<0.01) in HAF group (86.7%) than in FBS (6.7%). To culture oocytes in FBS were very effective in preventing ZP hardening. However cultured oocytes in HAF showed high rate of ZP hardening (p<0.01). Conclusions: These results suggest that HAF can be used as a supplement for the NM of mouse immature oocytes in vitro. However, HAF induces spontaneous hardening of ZP of mouse immaure oocytes during maturation in vitro.

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불임 여성의 난소로부터 회수된 미성숙 난자의 체외 성숙과 배양에 관한 연구 (Study on In Vitro Maturation and Culture of Immature Oocytes Collected from Ovaries of Infertile Women)

  • 이석윤;손원영;윤산현;이원돈;박창식;임진호
    • Clinical and Experimental Reproductive Medicine
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    • 제30권4호
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    • pp.333-340
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    • 2003
  • Objective: This study was performed to examine the maturation and the development to the blastocyst stage of immature oocytes collected from patients with high risk of ovarian hyperstimulation syndrome (OHSS). Materials and Methods: Cumulus-oocyte complexes (COCs) were collected following only HCGpriming for non stimulated IVF-ET cycles of the patients. At the time of oocyte collection, COCs were classified into three groups in accordance with their appearance (Group I: oocytes with dispersed cumulus cells; Group II: oocytes with compacted cumulus cells; Group III: oocytes with sparse cumulus cells). The in vitro maturation and blastocyst development rates of the COCs were compared among these groups. From August 2001 to June 2002, 48 IVM/IVF-ET cycles from 42 patients (mean age: $32.4{\pm}3.8$ years) were performed. To prevent the occurrence of OHSS, the patients were primed with 10, 000 IU HCG alone 36 h before oocyte collection without gonadotropin stimulation. Oocytes were aspirated on cycle days from 7 to 13. The normal COCs were classified into three groups according to their appearance. The aspirated immature oocytes were cultured in YS maturation medium containing 30% (v/v) human follicular fluid (HFF), 1 IU/ml FSH, 10 IU/ml HCG and 10 ng/ml rhEGF. Fertilization was induced by intracytoplasmic sperm injection (ICSI). All zygotes were co-cultured with cumulus cells in $10{\mu}l$ YS medium containing 10% HFF until day 7 after oocyte collection. Blastocyst transfer was performed on day 5 after ICSI. Results: Th e mean number of oocytes cultured in the IVM/IVF cycles was $24.7{\pm}10.6$. Of 1185 COCs, those assigned to Group I, II and III were 470 (39.7%), 414 (35.0%) and 301 (25.4%), respectively. The maturation rate (94.5%, 444/470, p<0.05) in Group I was significantly higher than those of Group II (62.8%, 260/414) and Group III (73.1%, 220/301). Especially, 30.9% of COCs in Group I (145/470) was matured on the day of oocyte aspiration. There were no differences in the rates of fertilization and cleavage among the three groups. The development rate to the blastocyst stage in Group I (54.6%, 206/377, p<0.05) was also significantly higher than those in Group II (33.0%, 68/206) and Group III (30.1%, 52/173). Twenty-four clinical pregnancies (50.0%) was obtained and 22 pregnancies (45.8%) are ongoing. Implantation rate in the present study was 24.6%. Conclusion: These results suggest that there is a positive correlation between the appearance of COCs and the developmental competence of the immature oocytes in non stimulated IVM/IVF cycles.