Predictive factors of exclusive breastfeeding attrition at Week 6 post-partum among mothers of preterm infants based on the theory of planned behaviour.

Breastfeeding plays an important role in the growth and development of preterm infants, and exclusive breastfeeding (EBF) in the first 6 weeks post-partum is the key to continuous breastfeeding. This study was designed to explore the influencing factors that contribute to breastfeeding attrition among mothers of preterm infants at Week 6 post-partum based on the theory of planned behaviour (TPB). We herein adopted a prospective observational study design in which 97 mothers who exclusively breastfed at Week 6 post-partum at a tertiary specialised hospital in Shanghai from June 2021 to February 2022 were taken as the EBF group, and 179 mothers without EBF were assigned to the EBF attrition group. Through an extensive literature review and expert consultation, we determined the possible factors influencing EBF attrition, analysed those factors that showed statistical significance in our univariate analysis by applying binary logistic regression, and constructed a nomogram model for predicting EBF attrition. The results revealed that negative breastfeeding sentiment (odds ratio [OR] = 1.006; 95% confidence interval [CI], 1.000-1.011) generated a greater risk of breastfeeding attrition. However, positive breastfeeding sentiment (OR = 0.991; 95% CI, 0.983-0.999), social and professional support (OR = 0.993; 95% CI, 0.987-0.999), breastfeeding control (OR = 0.945; 95% CI, 0.896-0.996), knowledge (OR = 0.893; 95% CI, 0.799-0.998), and intention to EBF at Week 6 post-partum (OR = 0.522; 95% CI, 0.276-0.988) were the protective factors and facilitated the development of our nomogram model. The Hosmer-Lemeshow goodness-of-fit test generated a χ2 value of 11.344 (p = 0.183) and an area under the curve of 0.822 (95% CI, 0.771-0.873). The C-index was 0.800 in the internal bootstrap validation, indicating that the nomogram model possessed favourable predictive accuracy and discrimination.

A randomized double blind comparison of atosiban in patients with recurrent implantation failure undergoing IVF treatment.

BACKGROUND: Patients with recurrent implantation failure (RIF) may have more uterine contractions. Several observational studies suggested that atosiban administration around embryo transfer resulted in higher pregnancy rates in RIF patients. This study aimed to evaluate the effect of atosiban given before fresh embryo transfer on pregnancy outcomes of women with RIF. METHODS: A prospective, randomized, double-blind controlled clinical trial was performed in IVF center of Shanghai First Maternity and Infant Hospital. According to a computer-generated randomization list, 194 infertile women with RIF received fresh embryo transfer between July 2017 and December 2019 were randomly allocated into the atosiban (n = 97) and the placebo (n = 97) groups. Women in the treatment group received atosiban intravenously about 30 min before embryo transfer with a bolus dose of 6.75 mg over one minute. Those in the placebo group received only normal saline infusion for the same duration. RESULTS: There was no significant difference in the live birth rate between the atosiban and placebo groups (42.3% vs 35.1%, P = 0.302, RR = 1.206 (0.844-1.723)). No significant differences were found between the two groups in the positive pregnancy test, clinical pregnancy, ongoing pregnancy, miscarriage, multiple pregnancy, ectopic pregnancy and implantation rates. Similar results were found when stratified by the number of embryos previously transferred, number of previous failed embryo transfers, frequency of endometrial peristalsis on embryo transfer day (≥ 3 waves/min) or serum estradiol (E2) on the day of hCG above the median level. And, there was no correlation between the serum E2 level on the day of hCG and the frequency of endometrial peristalsis on embryo transfer day. The frequency of endometrial peristalsis on embryo transfer day, total FSH/HMG dosage and duration were the significant factors which independently predicted the likelihood of a live birth. CONCLUSIONS: These results suggested that atosiban treatment before fresh embryo transfer might not improve the live birth rate in RIF patients. TRIAL REGISTRATION: The study had been approved by the Institutional Review Board of the hospital (2017 ethics No.43) and was registered under Clinicaltrials.gov with an identifier NCT02893722.

Probing the glass transition in reversible cross-linked polymer composites.

Understanding the nature of glass transition is still a great challenge. Glass transition is widely observed in many glassy materials; however, it has never been unambiguously observed in reversible cross-linked polymer, which is an ideal model of the percolation process. Herein, we report the synthesis of a reversible cross-linked polymer incorporated with four-armed Diels-Alder (DA) dynamic covalent bonds, and the robust experimental observation of percolation-induced glass transition in this reversible four-armed cross-linked polymer (DAMF1). Temperature-modulated differential scanning calorimetry (TMDSC) experiment results clearly revealed the presence of a glass transition along with an endothermic or exothermic peak associated with DA/retro-DA (RDA) reaction related to the reconstitution/disassociation of the DAMF1's four-armed cross-linked network. In situ 13C variable-temperature solid-state NMR experiments further confirmed the DA/RDA reaction during glass transition at a molecular level. The above experimental results provide a direct experimental evidence for the recently developed percolation model of glass transition, which provides new insights into the nature of glass transition.