Reproduction Abstracts

Introduction: Preimplantation embryos depend on nutrients provided in the reproductive tract for development. Early human embryos have an increasing requirement for amino acids as they develop from the 1-cell through to the blastocyst stage. In vivo, the uterus provides the final environment for preimplantation development, but surprisingly, the nutritional composition of human uterine fluid has been little investigated. This study aims to examine the amino acid composition of human uterine fluid and how this alters with maternal diet.

Materials and method: The gynaecological history and a validated, food frequency questionnaire was completed by all women recruited to this study. Uterine fluid was obtained from 56 women aged 18–45, undergoing Hystero-Salpingo-Contrast-Sonography with ethical approval (08/H0502/162). Reverse phase high pressure liquid chromatography (HPLC) was used to analyse the amino acid concentrations within the uterine fluid.

Results and discussion: Human uterine fluid contained an amino acid concentration of 4.92±0.53 mM. Glutamate was present in the highest concentration in uterine fluid followed by glycine and alanine. In contrast, methionine and tryptophan were present in the lowest concentration. Several amino acids including the branched chain amino acids (P<0.05) were found to be increased in those women with a negative compared to a positive prudent diet score. These data suggest that maternal diet has a significant impact on the amino acid composition of the uterine fluid. Further research is required to determine the impact of maternal diet during the periconceptional period and how this may affect both the in utero environment and embryo development.