Sequence of implantation and fetal and placental weights in the rat.
Rats (30) were injected intravenously with Evans blue dye on Day 5 of gestation and their uteri were examined to determine the position of early implantations. On Day 7 they were examined again for late implantations. Fetal sex and fetal and placental weights were determined at Day 22 (15 rats). The distribution of the 20% early implantations appeared random with respect to position in the uterine horn. There was no difference in fetal weight, placental weight or sex ratio between early and late implanting embryos.
D000818:Animals; D001835:Body Weight; D010064:Embryo Implantation; D005260:Female; D005333:Fetus; D009929:Organ Size; D010920:Placenta / Q000033:anatomy & histology*; D011247:Pregnancy; D051381:Rats; D012737:Sex Factors; D014599:Uterus / Q000033:anatomy & histology