Anatomy study note · Pregnancy
Placenta
The organ, formed by fetal chorion and the maternal decidua, through which the fetus gets oxygen and nutrition and gets rid of waste. Maternal blood fills the intervillous space; fetal blood flows in vessels inside the villi, and the two never mix.
Key points
- Maternal surface = decidual (basal) plate, cotyledons; fetal surface = chorionic plate + amnion.
- Term: ~500 g, 6–8 in. across.
- Barrier: haemo-choreal; maternal and fetal blood never mix.
- Hormones: progesterone, oestrogens, hCG, hCS.
- Placenta praevia → bleeding.
- Barrier: endothelium + basal laminae + cytotrophoblast + syncytiotrophoblast.
- Placenta: hCG, hCS, progesterone.
The full note in the atlas also covers
Features · Blood supply · Histology · Development · Clinical notes
Sign in free to see it on the 3D model, read the full note and practise questions on it.
Written from
- Inderbir Singh’s Human Embryology, ch. 6, PDF pp. 76–81, 82–86, 88–91
- BRS Cell Biology & Histology, 7th ed., ch. 19, PDF pp. 349, 355–356
More from the pregnancy
Privacy policy · Designed by DATXOC LLC.