Abnormal timing and spacing of embryo implantation after intrauterine fluid infusion caused pregnancy loss at mid-gestation.

<p>(<b>A</b>) Demonstrative photos of Day12 uteri after 0 μl and 10 μl intrauterine fluid infusion on Day4 morning. Red arrows showed abnormal implantation sites (retarded growth/crowded site). (<b>B</b>) Embryo resorption rate at Day12 after 0 μl, 10 μl and 20 μl intrauterine fluid infusion on Day4 morning (*<i>P</i> < 0.05, **<i>P</i> < 0.01) <i>t</i> test, Error bars represent S.E.M ). (<b>C</b>) Representative photos of normal embryo and retarded/resorbed embryos from 0μl and 10 μl groups at Day12. (<b>D</b>) Examples of twin pregnancy discovered at crowed implantation sites on Day12, note that two embryos were grown on one placenta, in the right panel, one of the twin embryo showed severely retarded growth and tended to be resorbed. (<b>E</b>) Average litter size at birth (**<i>P</i> < 0.01) <i>t</i> test, error bars represent S.E.M. Numbers within bars indicate the number of mice examined.