calculated litter size measurement number of blastocysts/embryos lost postimplantation to litter size ratio 2014-05-27T16:43:38Z A calculated measurement in which the number of blastocysts and/or embryos which die between implantation of the blastocyst and birth is divided by the total number of offspring in the litter, and the result presented as a ratio, fraction, quotient or percentage. CMO:0002382 JSmith VT:0003984 clinical_measurement_ontology percent postimplantation loss postimplantation loss of blastocysts/embryos as percentage of total litter ratio of the number of blastocysts/embryos lost postimplantation to the total number of offspring calculated offspring mortality measurement