Sonographer-guided frozen embryo transfer vs ultrasound-assisted frozen embryo transfer - A randomised controlled study.

BACKGROUND: The use of ultrasound to guide placement of the embryo during in vitro fertilisation (IVF) is important, but there are times where a good image cannot be obtained. Having a trained sonographer perform the ultrasound may therefore improve the success of embryo transfer. AIM: To determine whether the routine use of a sonographer to guide embryo transfer is superior to standard care. MATERIALS AND METHODS: Randomised, controlled, prospective clinical study in a private infertility clinic. There were 113 women aged <38 years undergoing frozen embryo transfer (donor egg/embryo excluded) who were randomised to sonographer-guided embryo transfer or standard care (the doctor performs an ultrasound prior to embryo transfer and the patient holds the ultrasound probe). The primary outcome was visualisation of the air bubble, and secondary outcomes were distance of the air bubble from the fundal endometrium, pregnancy rate (gestational sac on ultrasound at seven weeks) and live birth rate. RESULTS: The bubble was visualised in 100% of embryo transfers with a sonographer compared to 83% in the ultrasound-assisted group, and this was statistically significant (P < 0.01). No statistically significant differences were found in terms of distance from the fundal endometrium or in pregnancy rate and live birth rate. CONCLUSION: Sonographer-guided embryo transfer leads to statistically higher rates of visualisation of the air bubble compared to ultrasound-assisted transfer.

Characterization of the solvation environment provided by dilute aqueous solutions of novel siloxane polysoaps using the fluorescence probe pyrene.

Solubilization environment afforded by several of the novel allyl glycidyl ether-modified methylhydrosiloxane polymers are investigated using a common polycyclic aromatic hydrocarbon fluorescence probe, pyrene. The backbone of the polymer has been modified by the addition of an alkyl chain of varying length (either C8, C12, or C18) and to differing degrees of substitution. The nomenclature adopted for the purposes of these studies is as follows: "AGENT" represents the backbone polymer with no alkyl substitution, and "OAGENT", "DAGENT", and "SAGENT" are substituted with n-octyl, n-dodecyl, and n-octadecyl, respectively. The percentage of alkyl substitution is designated as 10, 15, and 20%. The pyrene polarity scale (defined as the ratio of the intensity of peak I to peak III) was used to determine the relative dipolarity of the cybotactic region provided by approximately 1 w/w% aqueous polymer solutions compared to 10 mM sodium dodecylsulfate (SDS) micellar solution. Results indicate that 10-15% DAGENT afforded the most hydrophobic solubilization site, followed by 15% OAGENT and 15% SAGENT. In addition, as the degree of alkyl substitution of DAGENT increased from 10 to 20%, the cybotactic region appeared to become more hydrophobic. Furthermore, a deeper investigation into the relative size of the solubilization site revealed that all alkyl-substituted polymers promoted excimer formation at relatively low pyrene concentrations, indicating the possibility of localized concentration enhancement within the solvation pockets and/or compartmentalization of the solute molecules. The pyrene fluorescence excitation data strongly indicates ground-state heterogeneity that is most prominent in AGENT and decreases as the alkyl chain length is increased. This provides a relative sense of the size and shape of the solvation pockets afforded by each polymer solution. An overall analysis of the collected data indicated that these alkyl-substituted polymers may provide a more selective and efficient pseudostationary phase in electrokinetic chromatography with better solvation capacity for hydrophobic compounds compared to SDS.