Akira Iwase

Prof. Dr. Akira Iwase

Department of Obstetrics and Gynecology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi 371-8511, Japan
orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
2 February 2011 in Human Reproduction
Verified
Journal Article
Open access
PDF file
WHWakana Hirokawa
Wakana Hirokawa
Akira IwaseAkira Iwase
Akira Iwase
MGMaki Goto
Maki Goto
STSachiko Takikawa
Sachiko Takikawa
YNYoshinari Nagatomo
Yoshinari Nagatomo
FKFumitaka Kikkawa
Fumitaka Kikkawa
To assess the impact of ovarian cystectomy for endometriomas on the ovarian reserve, we evaluated the pre- and post-operative levels of serum anti-Müllerian hormone (AMH). We also analyzed the correlations between factors related to endometriosis and surgery for endometriomas and the serum AMH levels to investigate which factors affect ovarian reserve. Thirty-eight patients who were undergoing ovarian cystectomy for unilateral endometrioma (n = 20) and bilateral endometriomas (n = 18) participated. Preoperative and post-operative serum samples were collected and assayed for AMH levels, and changes between the two samples were analyzed in association with parameters of endometriosis and surgery for endometriomas. The mean AMH level was 3.9 ng/ml prior to surgery, and was reduced to 2.1 ng/ml at 1 month post-surgery. The rate of decline of the serum AMH level was significantly higher in the bilateral group than the unilateral group (62.8 ± 29.6 versus 24.7 ± 32.5%, P < 0.001). The rate of decline in the serum AMH levels showed a significant correlation to the revised American Society for Reproductive Medicine (rASRM) score (P = 0.003), but not age, cyst diameter, blood loss during the operation or the number of follicles removed in the specimens. Our results suggest that the decrease in ovarian reserve should be taken into account in patients indicated for cystectomy for bilateral endometriomas or unilateral endometrioma with high rASRM scores.

1 December 2010 in Fertility and Sterility
Verified
Journal Article
Closed access
Akira IwaseAkira Iwase
Akira Iwase
WHWakana Hirokawa
Wakana Hirokawa
MGMaki Goto
Maki Goto
STSachiko Takikawa
Sachiko Takikawa
YNYoshinari Nagatomo
Yoshinari Nagatomo
FKFumitaka Kikkawa
Fumitaka Kikkawa

2 February 2010 in Journal of Assisted Reproduction and Genetics
Verified
Journal Article
Open access
PDF file
TNTatsuo Nakahara
Tatsuo Nakahara
Akira IwaseAkira Iwase
Akira Iwase
MGMaki Goto
Maki Goto
THToko Harata
Toko Harata
MSMiyabi Suzuki
Miyabi Suzuki
HAHisao Ando
Hisao Ando
To assess the effects of light from an integrated optical microscope and evaluate the safety of time-lapse observations using a built-in microscope incubator. We prospectively compared the fertilization rate and embryonic morphology after intracytoplasmic sperm injection between embryos cultured with time-lapse observations every 15 min in an incubator with an integrated optical microscope and embryos with intermittent observations (once a day) in conventional incubators. No significant differences were observed in the fertilization rate (57.5% vs. 57.5%) or the rate of excellent-good cleavage embryos (36.0% vs. 36.0%). These results suggest that time-lapse observations using an incubator with an integrated optical microscope may therefore be safely utilized in clinical practice.

23 November 2015 in Reproductive Medicine and Biology
Verified
Journal Article
Open access
PDF file
Akira IwaseAkira Iwase
Akira Iwase
TNTomoko Nakamura
Tomoko Nakamura
SOSatoko Osuka
Satoko Osuka
STSachiko Takikawa
Sachiko Takikawa
MGMaki Goto
Maki Goto
FKFumitaka Kikkawa
Fumitaka Kikkawa
Ovarian reserve reflects the quality and quantity of available oocytes. This reserve has become indispensable for the better understanding of reproductive potential. Measurement of the serum anti‐Müllerian hormone (AMH) level allows quantitative evaluation of ovarian reserve. It has been applied to a wide range of clinical conditions, and it is well established that the measurement of serum AMH levels is more useful than qualitative evaluation based on the menstrual cycle. AMH levels are monitored during infertility treatments; in patients undergoing medically assisted reproductive technology; and in the diagnosis of ovarian failure, polycystic ovarian syndrome, and granulosa cell tumor. It is also useful in the evaluation of iatrogenic ovarian damage. Population‐based studies have indicated a potential role for serum AMH in the planning of reproductive health management. While AMH is currently the best measure of ovarian reserve, its predictive value for future live births remains controversial. Furthermore, there is a serious practical issue in the interpretation of test results, as currently available assay kits use different assay ranges and coefficients of variation due to the absence of an international reference standard. The pros and cons of the serum AMH level as a definitive measure of ovarian reserve merits further review in order to guide future research.

3 November 2023 in Frontiers in Endocrinology
Verified
Journal Article
Open access
Akira IwaseAkira Iwase
Akira Iwase
YHYuko Hasegawa
Yuko Hasegawa
YTYumiko Tsukui
Yumiko Tsukui
MKMio Kobayashi
Mio Kobayashi
HHHikaru Hiraishi
Hikaru Hiraishi
YKYoshikazu Kitahara
Yoshikazu Kitahara
Anti-Müllerian hormone (AMH), an indirect indicator of the number of remaining follicles, is clinically used as a test for ovarian reserve. Typically, a decline suggests a decrease in the number of remaining follicles in relation to ovarian toxicity caused by interventions, which may implicate fertility. In contrast, serum AMH levels are elevated in patients with polycystic ovary syndrome. AMH is produced primarily in the granulosa cells of the preantral and small antral follicles. Thus it varies in association with folliculogenesis and the establishment and shrinking of the follicle cohort. Ovarian activity during the female half-life, from the embryonic period to menopause, is based on folliculogenesis and maintenance of the follicle cohort, which is influenced by developmental processes, life events, and interventions. AMH trends over a woman’s lifetime are associated with in vivo follicular cohort transitions that cannot be observed directly.

14 November 2007 in Journal of Assisted Reproduction and Genetics
Verified
Journal Article
Closed access
PDF file
MGMaki Goto
Maki Goto
Akira IwaseAkira Iwase
Akira Iwase
HAHisao Ando
Hisao Ando
SKShozo Kurotsuchi
Shozo Kurotsuchi
THToko Harata
Toko Harata
FKFumitaka Kikkawa
Fumitaka Kikkawa