Cryotop vitrification as compared to conventional slow freezing for human embryos at the cleavage stage: survival and outcomes.

OBJECTIVE: This study was conducted to compare the efficacy of cryotop vitrification of human cleavage-stage embryos to that of conventional slow freezing of these embryos with respect to survival. A second objective was to compare the two cryopreservation techniques with respect to outcomes for a cohort of women. MATERIALS AND METHODS: Cleavage-stage embryos from 102 patients were cryopreserved either by vitrification (57 patients) or by traditional slow freezing (45 patients). After thawing, rates of embryo survival, implantation, and clinical pregnancy were determined. RESULTS: Survival of embryos was significantly higher with the vitrification procedure as compared to traditional slow freezing [287/298 (96.3%) vs. 294/446 (65.9%); p < 0.05). Rates of implantation and clinical pregnancy were also significantly higher using vitrification procedure as compared to the slow freezing procedure (24.3% vs. 7.1% and 35.6% vs. 15.6% respectively, p < 0.05). CONCLUSION: As compared to conventional slow freezing, cryopreservation of human cleavage-stage embryo using vitrification results in higher rates of embryo survival, implantation, and clinical pregnancy. Vitrification therefore represents the superior cryopreservation technique for cleavage-stage embryos.

Relationship of follicular size to the development of intracytoplasmic sperm injection-derived human embryos.

OBJECTIVE: To compare the embryonic development of oocytes obtained from follicles of different sizes. MATERIALS AND METHODS: Oocytes (n = 819) were retrieved from women at 40 years of age or younger during 86 in vitro fertilization cycles and categorized as small, medium, or large based on the estimated volume of follicular fluid at the time of retrieval. RESULTS: The rates of good quality embryos from the large, medium, and small groups on days 2 and 3 were 76.85% and 66.20%, 74.00% and 61.33%, and 69.81% and 58.49%, respectively. There were no significant differences in the rates of good quality embryos between the three follicular volume groups. CONCLUSION: Even though fewer oocytes completed maturation in the small follicle group than in the other two groups, the quality of the embryos in all three groups was the same on days 2 and 3. These findings suggest that follicles of all sizes should be aspirated during the intracytoplasmic sperm injection cycle as follicles of every size were a good source of embryos.

Uterine position change between mock and real embryo transfers.

OBJECTIVE: This study was designed to assess the change in uterine position between mock and real embryo transfers. MATERIALS AND METHODS: A total of 386 embryo transfer cycles were reviewed, and the uterine position was recorded at the time of mock embryo transfer and then again at the time of real embryo transfer. RESULTS: Of 254 patients with an anteverted uterus at mock transfer, only 3 (1.2%) were found to have a retroverted uterus at actual embryo transfer. Of 132 patients with a retroverted uterus at mock transfer, 24 (18%) had an anteverted uterus at actual embryo transfer (p < 0.0001). CONCLUSION: Routine ultrasound-guided embryo transfer is suggested when a retroverted uterus is found at mock embryo transfer, as there is a significant chance that the uterine position will change.

Distinction between paternal and maternal contributions to the tripronucleus in human zygotes obtained after in vitro fertilization.

OBJECTIVE: The aim of this study was to determine the genetic composition of tripronuclear (3PN) zygotes. Fluorescence in situ hybridization (FISH) was used to quantify the sperm tails in human 3PN zygotes. MATERIALS AND METHODS: Ovarian hyperstimulation was performed using a standard long protocol consisting of gonadotropin-releasing hormone agonist (GnRHa) with human menopausal gonadotropins (HMG) and/or recombinant follicle stimulating hormone (rFSH). Human chorionic gonadotropin (hCG) was administered when at least two leading follicles reached 18 mm in mean diameter. Oocytes were retrieved from the follicles transvaginally under ultrasound guidance 34-36 hours after administration of hCG. The oocytes were examined 16-18 hours after fertilization for the presence and number of pronuclei. The 3PN zygotes were then fixed and extracted in buffer at 37 degrees C for 60 minutes. After washing in a blocking solution, the 3PN zygotes were prepared for indirect immunofluorescence using monoclonal antibody and Hoechst dye 33342 to visualize the number of pronuclei. RESULTS: Twenty-one 3PN zygotes were randomly collected for evaluation. The number of 3PN zygotes containing one, two or four sperm tails were two (10%), 18 (85%) and one (5%), respectively. CONCLUSION: Based on our observations, additional pronuclei are mainly of paternal origin.

Comparison of day 2 tubal embryo transfer with day 3 embryo transfer into the uterus of intracytoplasmic sperm injection derived human embryos.

OBJECTIVE: To compare the results of embryo transfer into the uterus (ET) performed on day 3 vs. tubal embryo transfer (TET) on day 2 in couples diagnosed with male factor infertility. MATERIALS AND METHODS: We collected data from 34 and 110 patients who underwent intracytoplasmic sperm injection (ICSI) followed by either TET on day 2 or ET on day 3 (January 2001-June 2005), respectively. All couples were diagnosed with male factor infertility; there were no tubal or uterine factors, diminished ovarian reserve, pelvic adhesions, history of polycystic ovary syndrome or previous ovarian surgery. RESULTS: The clinical pregnancy rates of day 2 TET and day 3 ET following ICSI were 64.71% and 57.27% (p > 0.05), respectively. The corresponding implantation rates were 35.47% and 29.58% (p > 0.05), respectively. CONCLUSION: The implantation and clinical pregnancy rates of ET on the 3rd day following ICSI were similar to the rates obtained with TET 2 days after ICSI. Therefore, ET performed 3 days after ICSI should be the first choice for couples with male factor infertility, while day 2 TET remains a good alternative, especially for women with normal tubal function and known difficulties of transcervical ET.

Effect of endometrial cavity fluid on clinical pregnancy rate in tubal embryo transfer (TET).

PURPOSE: In this study, we assess whether the endometrial cavity fluid (ECF) generated physiologically by the genital tract have negative effect on the pregnancy rate during tubal embryo transfer (TET) in patients who do not have hydrosalpinx or bilateral tubal obstruction. METHODS: We retrospectively collected samples from 176 women with 195 cycles receiving TET due to male factor, unexplained infertility or endometriosis from June 1999 to Dec. 2003, and divided them into two groups (group I: patient with fluid accumulation >1 mm in the anterior-posterior diameter in the uterine cavity; group II: patient without fluid accumulation in the uterine cavity). Endometrium thickness was measured as a maximal distance between anterior and posterior myometrium-endometrium interface under the long-axis view. The A-P diameter of ECF was measured via vaginal sonar on the day of ovum pick-up (OPU). RESULTS: From a total of 195 ART cycles involving 176 patients, the accumulation of ECF was detected in 10 cycles (5.1%). Seven of ten cycles (70%) with the accumulation of ECF were proved to be pregnant clinically. However, in the rest 185 cycles (group II), 98 of them (53%) were proved to be pregnant. At the mean time, the implantation rate was 29.03% and 25.71% in the groups I and II, respectively. No significant difference of the clinical pregnancy rate and the implantation rate was found between the two groups. CONCLUSIONS: According to our study, if the ECF was generated physiologically by the genital tract during controlled ovarian hyperstimulation (COH), the clinical pregnancy rate is not worse and no influence of embryo implantation was found.

Tubal pregnancy following tubal embryo transfer into the contralateral fallopian tube.

Ectopic and heterotopic pregnancy may occur with increased frequency following assisted reproductive technology (ART) procedures. In addition, there may be unusual sites of implantation, which may cause atypical and confusing clinical manifestations. We present a case of tubal pregnancy after tubal embryo transfer (TET) to the contralateral fallopian tube. Four embryos were transferred to the left fallopian tube by laparoscopy, but the patient developed a right tubal pregnancy, possibly as a result of intrauterine or intra-abdominal migration of the embryo. ART patients must be followed closely soon after the procedure, and there should be a high index of suspicion for an unusual implantation site.

Poor response of ovaries with endometrioma previously treated with cystectomy to controlled ovarian hyperstimulation.

PURPOSE: To compare ovarian response to controlled ovarian hyperstimulation (COH) between normal ovaries and ovaries previously treated surgically for unilateral ovarian endometrioma. METHODS: From January 1996 to December 2001, 32 patients with unilateral ovarian endometrioma previously treated surgically underwent 38 cycles of COH. Their records were reviewed retrospectively. The number of dominant follicles observed on the day of hCG injection and the number of eggs retrieved from the diseased and the normal ovaries in each patient were compared. RESULTS: The numbers of dominant follicles from diseased and normal ovaries were 1.9 +/- 1.5 and 3.3 +/- 2.1, respectively (P < 0.001). During ovum pick up, the numbers of eggs retrieved from diseased and normal ovaries were 2.9 +/- 2.6 and 6.1 +/- 4.1, respectively (P < 0.0001). For diseased ovaries, 21.1% (8/38) had no dominant follicles, while only 7.9% (3/38) of normal ovaries lacked dominant follicles. The clinical pregnancy rate and the implantation rate per embryo transfer were 33.3 and 17.6%. CONCLUSIONS: Surgery for ovarian endometrioma may damage ovarian reserve. It potentially results in poor ovarian response to COH, compared to the response of the contralateral normal ovary in the same individual.

Sperm morphology analysis using strict criteria as a prognostic factor in intrauterine insemination.

The objective of this study was to investigate the predictive value of Kruger's criteria for sperm morphology on intrauterine insemination (IUI) outcome. A total of 209 infertile patients underwent 244 IUI treatment cycles. These include 75 couples (80 cycles) with teratozoospermia and 134 couples (164 cycles) with unexplained infertility. The pregnancy rates per IUI cycle were 3.8 (1/26), 18.5 (10/54) and 29.9% (49/164) in patients with sperm morphology with <4, 4-9 and >9% normal forms, respectively, according to Kruger's criteria. A statistical difference in outcome was seen between couples with <4 and >9% normal forms (p = 0.005). Although the difference in pregnancy rates between those with 4-9 and <4% normal forms was not statistically significant, the pregnancy rate for those with 4-9% normal forms was acceptable and still higher than in those with <4% normal forms. Therefore, we suggest that IUI is a reasonable first-line therapy for patients with sperm morphology >4% normal forms, while couples with <4% normal forms should be advised to use in vitro fertilization with intracytoplasmic sperm injection instead of IUI.

Cessation of low-dose gonadotropin releasing hormone agonist therapy followed by high-dose gonadotropin stimulation yields a favorable ovarian response in poor responders.

PURPOSE: This study is a prospective nonrandomized study to determine the effect of a new protocol of controlled ovarian hyperstimulation (COH) using low doses and a half-period of gonadotropin releasing hormone agonist (GnRHa) followed by high doses of gonadotropin in patients who were supposed to be poor responders to standard long protocols of GnRHa administration. METHODS: From Dec 1996 to Nov 1998, 50 patients who were classified as "poor responders" were scheduled for 52 cycles of a modified controlled ovarian hyperstimulation protocol. They were categorized into 3 groups: a group of poor responders to COH in the previous IVF or IUI cycles, a group with elevated Day 3 FSH levels, and a group over the age of 40 years. All patients received GnRH agonist from the midluteal phase of the previous cycle to the onset of menstruation in the next cycle. Then high doses of gonadotropins (HMG/FSH) were given. The patients then had standard courses of in vitro fertilization and embryo transfer (IVF-ET) or transfallopian embryo transfer (TET). RESULTS: Six of the 52 cycles of the modified protocols were cancelled because of poor ovarian response. One premature ovulation was noted before ovum retrieval was performed. In the other 45 cycles, an average of 6.3 mature oocytes were retrieved. The total pregnancy rate and implantation rate were 20.5 and 11.5%, respectively. CONCLUSIONS: The low dose and half duration of GnRHa therapy lessened the suppression of the response of the ovaries to COH compared with the regular long protocol of GnRHa down regulation therapy. This resulted in a low cancellation rate (11.8%), a favorable embryo implantation rate (11.5%), and an acceptable clinical pregnancy rate (20.5%).