BGDA Practical Placenta - Placental Functions

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Human term placental volumes sorted by size (from table).

Term placental composition, villous capillarization and the mean cross-sectional areas of peripheral villi and capillaries, data from a study sample of 15 normal placenta (mean placental volume, 652 ml).

Variable	Unit	Placenta (mean, n = 15)
Intervillous space	mL	213
Stem villi	mL	71.4
Peripheral villi	mL	326
Trophoblast	mL	95.5
Stroma	mL	184
Fetal capillaries	mL	46.9
Non-parenchyma	mL	41.5
Peripheral villi	km	89.2
Fetal capillaries	km	310
TS area villi	µm2	3700
TS area capillary	µm2	150
Capillaries	mL mL-1	0.147
Length ratio	km km-1	3.6

Endocrine

Protein and steroid hormones.

• Human chorionic gonadotrophin (hCG) - like leutenizing hormone, supports corpus luteum in ovary, pregnant state rather than menstrual, maternal urine in some pregnancy testing
• Human chorionic somatommotropin (hCS) - or placental lactogen stimulate (maternal) mammary development
  • rise through pregnancy, stimulates maternal metabolic processes, breast growth
• Human chorionic thyrotropin (hCT)
• Human chorionic corticotropin (hCACTH)
• Relaxin
• Steroid Hormones - progesterone (maintains pregnancy), estrogens (fetal adrenal/placenta)

Terms

BGDA: Lecture 1 | Lecture 2 | Practical 3 | Practical 6 | Practical 12 | Lecture Neural | Practical 14 | Histology Support - Female | Male | Tutorial

Glossary Links

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Cite this page: Hill, M.A. (2024, April 25) Embryology BGDA Practical Placenta - Placental Functions. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/BGDA_Practical_Placenta_-_Placental_Functions

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G