T. Kuramoto

Implications of assisted reproductive technologies on term singleton birth weight: an analysis of 25,777 children in the national assisted reproduction registry of Japan

OBJECTIVE To evaluate the implications of assisted reproductive technologies (ART) on neonatal birth weight. DESIGN A retrospective study using analysis of covariance and multiple logistic regression analysis of the Japanese ART registry. SETTING Japanese institutions providing ART treatment. PATIENT(S) A total of 25,777 singleton neonates reaching term gestation following ART during the years 2007-2008, with 11,374 achieved through fresh embryo transfers (fresh ET) and 14,403 achieved through frozen-thawed embryo transfers (FET). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Birth weight. RESULT(S) The mean birth weight after FET was significantly higher compared with fresh ET and all Japanese births (3,100.7 ± 387.2 g, 3,009.8 ± 376.8 g, and 3,059.6 ± 369.6 g, respectively). The risk for low birth weight in FET was significantly lower compared with fresh ET. In fresh ET, ovarian stimulations were associated with about twofold risk of low birth weight compared with natural cycle. Regarding to the duration of embryonic culture, the risks resulting from a shorter culturing time were significantly higher compared with a longer culturing time in fresh ET. CONCLUSION(S) The best method of embryo transfer for fetal growth was FET after extended culturing until blastocyst stage. However, further investigations should be performed to understand the safety of ART treatment.

A successful pregnancy and live birth after intracytoplasmic sperm injection with globozoospermic sperm and electrical oocyte activation

OBJECTIVE To present the effectiveness of intracytoplasmic sperm injection (ICSI) using globozoospermic sperm and assisted oocyte activation by electrical stimulation. DESIGN A case report. SETTING A private IVF center in Japan. PATIENT(S) A man with globozoospermia. INTERVENTION(S) Acridine orange (AO) test, mouse oocyte activation test, and ICSI with electrical oocyte activation. MAIN OUTCOME MEASURE(S) Fertilization, pregnancy, and live birth. RESULT(S) In the first ICSI attempt, neither of the two injected oocytes fertilized. Staining of the patients sperm with AO showed that only 2.9% of the sperm emitted a green fluorescence at the characteristic round head (sperm with native DNA content). The mouse oocyte activation test using the roundheaded sperm showed that the normal fertilization rate was 78.9% when SrCl(2) was used for assisted oocyte activation; however, it was 6.0% without assisted oocyte activation. We confirmed that the sperm had defective ability to activate oocytes. In the second ICSI attempt, human oocytes were activated electrically with use of a single square direct current pulse after microinjection. All the seven injected oocytes fertilized normally, and two eight-cell embryos were transferred on day 3. Clinical pregnancy was confirmed, and a healthy girl weighing 2362 g was delivered at 37 weeks of gestation by cesarean section. CONCLUSION(S) This is the first successful outcome of ICSI using globozoospermic sperm and electrical oocyte activation. The electroactivation obviates the need for the use of potentially harmful drugs for activation.

Relatively poor oocyte quality is an indication for intracytoplasmic sperm injection

OBJECTIVE To determine the relation between the insemination method used and the quality of oocytes and embryos. DESIGN Prospective study. SETTING Assisted reproductive centers at Yamagata University Hospital and Kuramoto Womens Clinic in Yamagata, Japan. PATIENT(S) Forty patients undergoing IVF and 40 patients undergoing intracytoplasmic sperm injection (ICSI). INTERVENTION(S) To estimate oocyte quality, the granulosa cells surrounding the oocyte were fixed and stained with a commercial dye in both groups of patients. One thousand granulosa cells were examined under a fluorescence microscope. MAIN OUTCOME MEASURE(S) The incidence of apoptotic granulosa cells surrounding each oocyte. RESULT(S) The incidence of apoptosis in the granulosa cells enclosing the oocytes that were fertilized by IVF was significantly lower than that in the oocytes that were fertilized by ICSI. Moreover, the incidence of apoptosis in the granulosa cells enclosing the oocytes that grew into good-quality or fair-quality embryos was significantly lower after conventional IVF than after ICSI. With ICSI, the incidence of apoptosis was not significantly different among the granulosa cells surrounding the oocytes that were inseminated, were fertilized, or developed into good-quality or fair-quality embryos. With IVF, the incidence of apoptosis was highest in the granulosa cells surrounding the oocytes that were inseminated and lowest in the granulosa cells surrounding the oocytes that developed into good-quality and fair-quality embryos. CONCLUSION(S) A good-quality oocyte is necessary for the development of a good-quality embryo with IVF but not with ICSI. Thus, relatively poor oocyte quality is a good indication for the use of ICSI.

Perinatal outcome of twice-frozen-thawed embryo transfers: a clinical follow-up study

We evaluated our clinical data on refrozen-thawed ETs (92 cycles) and found that human embryos were capable of withstanding two freeze-thaw cycles, resulting in normal live births after transfer at a rate similar to that of primary frozen-thawed embryos. This is the first follow-up study to present perinatal outcomes of children born after embryo re-cryopreservation, and our results should encourage clinicians to explore the possibility of performing the refreezing procedure.

Injury to the endometrium prior to the frozen–thawed embryo transfer cycle improves pregnancy rates in patients with repeated implantation failure

This retrospective cohort study evaluated the effectiveness of injury to the endometrium prior to the frozen–thawed embryo transfer (FET) cycle in patients with repeated implantation failure (RIF) in our clinic.