Table 1 Embryo implantation in different species
Species | Arrival to the Uterine Cavity | Hatch | Conceptus Elongation | Recognition Signal of Pregnancy | Initiate Implantation | Firm Attachment | Placentation |
|---|---|---|---|---|---|---|---|
Homo sapiens | Day 4 | Day 4–5 | No | Human chorionic gonadotropin (hCG) | Day 6–7 | Day 8–10 | Hemochorial (invasive) |
Mus musculus | Day 3 | Day 4 | No | Prolactin (PRL) | Day 4 | Day 5–6 | Hemochorial (invasive) |
Bos taurus | Day 4–5 | Day 9–10 | Yes | Interferon tau (IFNT) | Day 19 | Day 40–45 | Synepitheliochorial (non-invasive) |
Sus scrofa | Day 2–2.5 | Day 6 | Yes | Estrogen | Day 12–13 | Day 25–26 | Epitheliochorial (non-invasive) |
Ovis aries | Day 3–4 | Day 7–8 | Yes | Interferon tau (IFNT) | Day 14–15 | Day 28–35 | Synepitheliochorial (non-invasive) |
Equus caballus | Day 6 | Day 7–8 | No | Unknown factor | Day 35–40 | Day 95–105 | Epitheliochorial (non-invasive) |