Long-term embryo vitrification is associated with reduced success rates in women undergoing frozen embryo transfer following a failed fresh cycle.

OBJECTIVE: To investigate the association of long-term embryo vitrification with the success rates and neonatal outcomes in frozen cycles. STUDY DESIGN: A single-center, retrospective cohort study was performed in Peking University Third Hospital. We included women who had undergone their first vitrified-warmed cycles following an unsuccessful fresh embryo transfer cycle between January 2013 and December 2019. Restricted cubic splines with 4 knots (at min-3.0 months, 3.1-6.0 months, 6.1-12.0 months, 12.1-max months) were used to map the non-linear relationship between live birth and embryo storage time as a continuous variable after adjustment for covariates. Multiple logistic regression was used to calculate crude odds ratios (OR) and adjusted OR (aOR) with 95 % confidence intervals (CI). RESULTS: A total of 10,167 women undergoing their first frozen cycle following an unsuccessful fresh embryo transfer cycle were included, among whom 3,708 resulted in a live birth (3,254 singleton live births). Restricted cubic splines, both before and after adjusting for covariates, showed that the predicted live birth rate (LBR) progressively decreased with an increase in the duration of embryo cryopreservation. This trend was also evident when women were categorized into four groups based on the length of cryopreservation. The live birth rate (LBR) was highest in the 0.8-3.0 months group (38 %) compared to the other groups. Multivariable logistic regression with the 0.8-3.0 months group as the reference, demonstrated that the 6.1-12.0 months group and >12.0 months group experienced lower live birth rates (aOR = 0.82 (0.72, 0.94) and aOR = 0.71 (0.57, 0.88), respectively). The LBR for the 3.1-6.0 months group was comparable to that of the 0.8-3.0 months group, with an aOR of 0.98 (0.90, 1.07). Sensitivity analyses in women who underwent single blastocyst transfer, in women with at least one good-quality embryo for transfer, and in women with age less than 36 at embryo transfer demonstrated a similar association between LBR and embryo frozen time. The neonatal outcomes were not significantly different among the four groups. CONCLUSIONS: Embryo vitrification greater than six months is associated with a reduction in success rate but does not appear to alter neonatal outcome.

Diagnostic role of multislice spiral computed tomography combined with clinical manifestations and laboratory tests in acute appendicitis subtypes.

The study aimed to investigate the diagnostic role of multislice spiral CT (MSCT) combined with clinical manifestations and laboratory tests in acute appendicitis subtypes. Patients diagnosed with acute appendicitis were included for retrospective analysis and their clinical manifestations and MSCT signs were analyzed. The clinical manifestations of different subtypes of acute appendicitis, including simple appendicitis, suppurative appendicitis and gangrenous appendicitis, were compared. The clinical manifestations were anorexia in 51.1% of patients, nausea and vomiting in 62.0%, shifting right lower abdominal pain in 51.1%, elevated body temperature in 31.2%, right lower quadrant abdominal tenderness in 91.4%, rebound tenderness in 91.4%, increased white cell count in 89.1%, high neutrophil count in 88.2%, increased appendiceal diameter enlargement in 100%, surrounding exudate in 95.0%, fecal stones in 51.6%, appendiceal wall thickening in 94.6%, lymph node in 82.8% and intestinal stasis in 18.6%. There were statistically significant differences in body temperature and neutrophil percentage among the subtypes of appendicitis and they were lowest in simple appendicitis and highest in gangrenous appendicitis. There were statistically significant differences in appendix diameter and the surrounding exudate among the subtypes of appendicitis and they were lowest in simple appendicitis and highest in gangrenous appendicitis. Clinical manifestations and MSCT signs, especially body temperature, percentage of neutrophils and the surrounding exudate, might have significant diagnostic value in acute appendicitis.