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A novel embryo identification system by direct tagging of mouse embryos using silicon-based barcodes

Posted: December 27, 2010 at 6:12 pm

BACKGROUND

Measures to prevent assisted reproductive technologies (ART) mix-ups, such as labeling of all labware and double-witnessing protocols, are currently in place in fertility clinics worldwide. Technological solutions for electronic witnessing are also being developed. However, none of these solutions eliminate the risk of identification errors, because gametes and embryos must be transferred between containers several times during an ART cycle. Thus, the objective of this study was to provide a proof of concept for a direct embryo labeling system using silicon-based barcodes.

METHODS

Three different types of silicon-based barcodes (A, B and C) were designed and manufactured, and microinjected into the perivitelline space of mouse pronuclear embryos (one to four barcodes per embryo). Embryos were cultured in vitro until the blastocyst stage, and rates of embryo development, retention of the barcodes in the perivitelline space and embryo identification were assessed every 24 h. Release of the barcodes after embryo hatching was also determined. Finally, embryos microinjected with barcodes were frozen and thawed at the 2-cell stage to test the validity of the system after cryopreservation.

RESULTS

Barcodes present in the perivitelline space, independently of their type and number, did not affect embryo development rates. The majority of embryos (>90%) retained at least one of the microinjected barcodes in their perivitelline space up to the blastocyst stage. Increasing the number of barcodes per embryo resulted in a significant increase in embryo identification rates, but a significant decrease in the barcode release rates after embryo hatching. The highest rates of successful embryo identification (97%) were achieved with the microinjection of four type C barcodes, and were not affected by cryopreservation.

CONCLUSIONS

Our results demonstrate the feasibility of a direct embryo labeling system and constitute the starting point in the development of such systems.

Recommendation and review posted by G. Smith

Factors influencing physicians’ advice about female sterilization in USA: a national survey

Posted: December 27, 2010 at 6:12 pm

BACKGROUND

Tubal ligation can be a controversial method of birth control, depending on the patient's circumstances and the physician's beliefs.

METHODS

In a national survey of 1800 US obstetrician-gynecologist (Ob/Gyn) physicians, we examined how patients’ and physicians’ characteristics influence Ob/Gyns’ advice about, and provision of, tubal ligation. Physicians were presented with a vignette in which a patient requests tubal ligation. The patient's age, gravida/parity and her husband's agreement/disagreement were varied in a factorial experiment. Criterion variables were whether physicians would discourage tubal ligation, and whether physicians would provide the surgery.

RESULTS

The response rate was 66% (1154/1760). Most Ob/Gyns (98%) would help the patient to obtain tubal ligation, although 9–70% would attempt to dissuade her, depending on her characteristics. Forty-five percent of physicians would discourage a G2P1 (gravida/parity) woman, while 29% would discourage a G4P3 woman. Most physicians (59%) would discourage a 26-year-old whose husband disagreed, while 32% would discourage a 26-year-old whose husband agreed. For a 36-year-old patient, 47% would discourage her if her husband disagreed, while only 10% would discourage her if her husband agreed. Physicians’ sex had no significant effect on advice about tubal ligation.

CONCLUSIONS

Regarding patients who seek surgical sterilization, physicians’ advice varies based on patient age, parity and spousal agreement but almost all Ob/Gyns are willing to provide or help patients obtain surgical sterilization if asked. An important limitation of the study is that a brief vignette, while useful for statistical analysis, is a rough approximation of an actual clinical encounter.

Recommendation and review posted by G. Smith

Ureteral endometriosis: clinical and radiological follow-up after laparoscopic ureterocystoneostomy

Posted: December 27, 2010 at 6:12 pm

BACKGROUND

Ureteral endometriosis is a rare entity that may lead to progressive hydroureteronephrosis and renal loss. When the localization of ureteral stenosis is close to the ureterovesical junction, ureterocystoneostomy may be required. The aim of the present study was to evaluate post-operative complication rates and clinical outcomes at 1- and 6-month follow-up after laparoscopic ureterocystoneostomy.

METHOD

Twenty patients who underwent ureterocystoneostomy for pelvic endometriosis in our tertiary referral centre for endoscopic surgery during 1 year were studied. A cystography was performed on Day 7 after surgery to verify the integrity of anastomosis and a satisfactory bladder capacity. Follow-up consisted of gynaecological examination and transvaginal ultrasound at 1 and 6 months after surgery. At 6 months, urography and cystography were also performed. Measurements included results of a pre-operative clinical and instrumental assessment, intra- and post-operative complications, post-operative bladder capacity at cystography and improvement of pain, using a visual analogue scale for the main symptoms related to endometriosis and uro-specific pain.

RESULTS

Neither a case of ureteral fistula nor other complications requiring re-intervention were reported. Post-operative transient deficit of bladder voiding occurred in five cases (25%), urinary infection in one and post-operative pyrexia in four (20%) patients. The median time to resuming voiding function was 3 days (range 1–20 days). In six cases, a mild vesico-ureteral reflux at the operated side was observed at 7-day cystography. Post-operative symptomatology was improved significantly (P<0.05) for all symptoms. Urography and cystography performed at 6 months confirmed good post-operative reconstructions in all cases.

CONCLUSIONS

The objective of surgical treatment of ureteral endometriosis is to remove the stenotic tract and to preserve renal function. In cases of intrinsic ureteral endometriosis, the procedure of laparoscopic ureterocystoneostomy is feasible and has good outcomes at short- and medium-termfollow-up.

Recommendation and review posted by G. Smith

Dioxins in ascites and serum of women with endometriosis: a pilot study

Posted: December 27, 2010 at 6:12 pm

BACKGROUND

Animal studies and laboratory experiments have demonstrated that exposure to dioxins may be involved in the pathophysiology of endometriosis. However, recent epidemiological investigations have shown conflicting results. Although peritoneal fluid is a specific microenvironment playing a pivotal role in the development of endometriosis, to our knowledge, there is no published study evaluating the concentrations of dioxins in serum and peritoneal fluid simultaneously. The present study explores the possible correlation between the local peritoneal fluid levels of dioxins and concurrent endometriosis.

METHODS

There were 17 infertile women enrolled in the present study. After the diagnostic laparoscopic examination, the women were divided into two groups: endometriosis (n = 10) and controls (n = 7). We measured 29 dioxins simultaneously in serum and peritoneal fluid samples: 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and 12 polychlorinated biphenyls (dioxin-like PCBs). A dioxin toxic equivalency (TEQ) system was utilized to calculate the dioxin concentration in each sample.

RESULTS

Serum concentrations of itemized components of 29 dioxins were similar in the endometriosis patients compared with the controls. Higher concentrations of PCDFs and dioxin-like PCBs were observed in peritoneal fluid than in serum, whereas the reverse was shown for PCDDs. Statistical analysis showed that higher levels of dioxin TEQ (PCDDs and PCDFs) in peritoneal fluid were significantly associated with an increased risk of endometriosis (OR: 2.5; 95% CI: 1.17–5.34; P = 0.035).

CONCLUSIONS

This is the first report suggesting that higher concentrations of dioxins (PCDDs and PCDFs) in peritoneal fluid are linked to endometriosis. More detail and epidemiological research is warranted to further explore this link.

Recommendation and review posted by G. Smith

Comparison of automated and manual follicle monitoring in an unrestricted population of 100 women undergoing controlled ovarian stimulation for IVF

Posted: December 27, 2010 at 6:12 pm

BACKGROUND

Ovarian response to gonadotrophin stimulation is monitored with serial ultrasound (US) examinations. Sonography-based Automated Volume Count (SonoAVC) is a relatively new three-dimensional (3D) US technology, which automatically generates a set of measurements including the mean follicular diameter (MFD) and a volume-based diameter (dV) for each follicle in the ovaries. The present study aimed to assess the applicability and reproducibility of this automated follicle measurement method in an IVF programme.

METHODS

For this prospective method comparison study, 100 women undergoing US monitoring of a controlled ovarian stimulation cycle were recruited. Each follicle was manually measured by taking the mean of maximal diameters on three orthogonal planes with two-dimensional (2D) US. A 3D volume of each ovary was then captured. The ovarian volumes were later analysed using SonoAVC. The agreement between the two methods for the numbers of follicles and the size of the leading follicle was assessed with the Bland–Altman method. The reproducibility of SonoAVC measurements was assessed with the intraclass correlation coefficient (ICC).

RESULTS

Both SonoAVC-generated MFD and dV-based follicle counts, as well as the leading follicle diameter, had good agreement with conventional 2D US measurements. SonoAVC measurements had very good reproducibility, with ICC ≥0.8 for most evaluations.

CONCLUSIONS

Automated follicle monitoring with SonoAVC can replace or be used interchangeably with conventional 2D measurements. Automated follicle monitoring can save time, provide a method of quality control and create opportunities for developing HCG criteria based on follicular volume or for monitoring patients from a distance.

Recommendation and review posted by G. Smith

The capacity of hysterosalpingography and laparoscopy to predict natural conception

Posted: December 27, 2010 at 6:12 pm

BACKGROUND

Laparoscopy has been claimed to be superior to hysterosalpingography (HSG) in predicting fertility. Whether this conclusion is applicable to a general subfertile population can be questioned as data in support of this claim were collected in third line centres. The aim of this study was to assess the prognostic capacity of HSG and laparoscopy in a general subfertile population.

METHODS

In 38 centres, we prospectively studied a cohort of patients referred for subfertility between 2002 and 2004, who underwent HSG and/or laparoscopy as part of their subfertility work-up. Follow-up started immediately after tubal testing and ended 12 months thereafter. Time to pregnancy was censored at the of date last contact, when the woman was not pregnant or at the start of treatment. Kaplan–Meier curves for the occurrence of spontaneous intrauterine pregnancy were constructed for patients without tubal pathology, for those with unilateral tubal pathology and for patients with bilateral tubal pathology at HSG or laparoscopy. Multivariable Cox regression analysis was used to calculate fecundity rate ratios (FRRs) to express associations between tubal pathology and the occurrence of an intrauterine pregnancy.

RESULTS

Of the 3301 included patients, 2043 underwent HSG only, 747 underwent diagnostic laparoscopy only and 511 underwent both. At HSG, 322 (13%) patients showed unilateral tubal pathology and 135 (5%) showed bilateral tubal pathology. At laparoscopy, 167 (13%) showed unilateral tubal pathology and 215 (17%) showed bilateral tubal pathology. Multivariable analysis resulted in FRRs of 0.81 [95% confidence interval (CI): 0.59–1.1] for unilateral, and 0.28 (95% CI: 0.13–0.59) for bilateral, tubal pathology at HSG. The FRRs at laparoscopy were 0.85 (95% CI: 0.47–1.52) for unilateral, and 0.24 (95% CI: 0.11–0.54) for bilateral, tubal pathology.

CONCLUSIONS

Patients with unilateral tubal pathology at HSG and laparoscopy had a moderate reduction in pregnancy chances, whereas those with bilateral tubal pathology at HSG and laparoscopy had a severe reduction in pregnancy chances. This reduction was similar for HSG and laparoscopy, suggesting that HSG and laparoscopy have a comparable predictive capacity for natural conception.

Recommendation and review posted by G. Smith


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