Comparison of transfers to Fallopian tubes or uterus after ICSI

A Rotating Spiral Micromotor for Noninvasive Zygote Transfer

Embryo transfer (ET) is a decisive step in the in vitro fertilization process. In most cases, the embryo is transferred to the uterus after several days of in vitro culture. Although studies have identified the beneficial effects of ET on proper embryo development in the earlier stages, this strategy is compromised by the necessity to transfer early embryos (zygotes) back to the fallopian tube instead of the uterus, which requires a more invasive, laparoscopic procedure, termed zygote intrafallopian transfer (ZIFT). Magnetic micromotors offer the possibility to mitigate such surgical interventions, as they have the potential to transport and deliver cellular cargo such as zygotes through the uterus and fallopian tube noninvasively, actuated by an externally applied rotating magnetic field. This study presents the capture, transport, and release of bovine and murine zygotes using two types of magnetic micropropellers, helix and spiral. Although helices represent an established micromotor architecture, spirals surpass them in terms of motion performance and with their ability to reliably capture and secure the cargo during both motion and transfer between different environments. Herein, this is demonstrated with murine oocytes/zygotes as the cargo; this is the first step toward the application of noninvasive, magnetic micromotor-assisted ZIFT.

Zygote intrafallopian tube transfer versus intrauterine cleavage or blastocyst stage transfer after intracytoplasmic sperm injection cycles in patients with repeated implantation failure: A prospective follow-up study

AIM

This study aimed to compare the outcomes between zygote intrafallopian transfer (ZIFT) with intrauterine day-3 (cleavage stage) embryo transfer and intrauterine day-5 (blastocyst stage) embryo transfer in patients undergoing intracytoplasmic sperm injection.

MATERIAL AND METHODS

This prospective study was performed at Royan Institute, Tehran, Iran, between January 2012 and January 2014. Two hundred fifty women with more than three unexplained implantation failures were divided non-randomly into three groups according to embryonic age and methods used as follows: (i) intrauterine cleavage-stage embryo transfer (n = 100); (ii) intrauterine blastocyst-stage embryo transfer (n = 50); and (iii) ZIFT (n = 100). Implantation, clinical pregnancy, miscarriage and live birth rates were our main outcomes.

RESULTS

Patients' characteristics and ovarian response were comparable among the three groups. Implantation rate (56.1% vs 27.9%) was significantly higher in the blastocyst group as compared to the ZIFT group; however, clinical pregnancy rate (38% vs 23%) was not statistically significantly different between the two groups, but due to the significantly higher miscarriage rate (34.7% vs 5.3%) in the ZIFT group, the live birth rate was significantly higher in the blastocyst group (P = 0.04). No significant differences were found between the cleavage-stage and blastocyst-stage groups in terms of implantation, clinical pregnancy, miscarriage and live birth rates.

CONCLUSION

We do not recommend the use of the ZIFT procedure for patients with repeated implantation failures. It seems that replication of cleavage- or blastocyst-stage embryo transfer is more efficient and affordable.

Comparison of unilateral and bilateral transfer of injected oocytes into fallopian tubes: a prospective, randomized clinical trial

OBJECTIVE

To assess whether pregnancy rate differs in unilateral vs. bilateral transfer in "immediate transfer of injected oocytes into the fallopian tubes."

DESIGN

Prospective randomized clinical trial.

SETTING

Tertiary university hospital.

PATIENT(S)

The study population included 160 patients presenting with male factor infertility who fulfilled the criteria for immediate transfer of injected oocytes into tubes.

INTERVENTION(S)

Four injected oocytes were transferred into two tubes (study group) or one tube (control group).

MAIN OUTCOME MEASURE(S)

Implantation rate, clinical pregnancy rate, multiple pregnancy rate, and incidence of pregnancy with unknown location (PUL).

RESULT(S)

A total of 72 (45%) pregnancies were achieved. There were 32 pregnancies (1 PUL, 4 multiple, and 27 singletons) in the bilateral transfer group and 40 pregnancies in the unilateral transfer group (1 PUL, 7 multiple, and 32 singletons). No significant difference was found in the implantation rate, clinical pregnancy rate, multiple pregnancy rate, and incidence of PUL.

CONCLUSION(S)

This study demonstrates that no difference in outcome occurred between unilateral and bilateral transfer in microinjected oocytes intrafallopian transfer (MIFT). Therefore, along with the same outcome parameters, unilateral transfer is the preferred method of MIFT.

Embryo transfer: hysteroscopic assessment of transfer catheter effects on the endometrium

So far as is known, this is the first series to report the effects of embryo transfers on endometrial integrity as assessed by direct hysteroscopic visualization. Subjects (n = 30) were patients of reproductive age undergoing diagnostic hysteroscopy. A mock embryo transfer was performed by a single clinician, immediately followed by saline hysteroscopy using a 2.7 mm hysteroscope. Hegar dilators or uterine sounds were not used. Representative video clips were recorded for independent assessment of endometrial integrity. (The movie sequence may be purchased for viewing on the internet at www.rbmonline.com/Article/1040; it is free to web subscribers.) Outcomes measured were ease of transfer (easy, moderate, difficult, very difficult) and details of the transfer technique. Endometrial damage was independently assessed and graded as follows: none, minor, moderate or severe. Of the easy transfers, 54% showed no endometrial damage. However, there 37% showed moderate to severe damage in the easy transfer group. Of the moderately difficult transfers, there was no clear association between perceived difficulty of transfer and amount of endometrial damage. Clinical perception of ease of transfer does not correlate well with the degree of endometrial disruption (P = 0.41). Use of hysteroscopy offers a unique insight into the effects of embryo transfer on endometrial integrity.