AMNIOTIC FLUID

 ORIGION:-

the origion of amniotic fluid is still remain unsolved .

it is probably of mixed origin maternal and fetal  maternal -in early pregnancy

fetal-  in late pregnancy 

⦁ in early pregnancy -as an ultra filtrate of maternal plasma 

⦁ by begning of the second trimester-diffusion through fetal skin.

⦁ after 20 weeks carnification of skin prevents this diffusion and amniotic fluid is composed of fetal urine 

⦁ others contributors --pulmonary fluid

          fluid filtering through the placenta

amniotic fluid - 98 -99% water 1to2% solid 

⦁ ph - 7.2 (7to7.5)

⦁ alkaline in nature  straw colored

⦁ Osmolarity – 250 m 05 m/L

⦁ fetal daily urine out put at term 400-1200 ml

⦁ completely replaced in every 3 hrs.

⦁ amniotic fluid inhibits bacterial growth due to phosphate to zinc ratio week of gestation -                          volume

    12 w  -50 ml 

    20w   - 400 ml

    36-38w -1000ml (max.)

    >38  -    600-800 ml

    at term -  600-800 ml

    post term>42-200 m

colours of amniotic fluid :-

⦁ early pregnacy -   colourless.

⦁ near term         - pale straw coloured

⦁ green            -     meconium stained / Indicate fetal distress 

⦁ greenish yellow   -      post   maturity

⦁ golden yellow  -          Rh incompatibility due to hemolysis 's

⦁ dark coloured     -        concealed haemorrhage

⦁ dark brown/tabaco juice  - in case of IUD (intra uterine            death)

FUNCTION OF AMNIOTIC FLUID :-

⦁ SHOCK ABSORBER 

⦁ MAINTAIN AN EVEN TEMPERATURE 

⦁ ALLOW GROWTH AND FREE MOVEMENT OF THE FETUS AND PREVENT ADHESION BETWEEN FETAL PART AND AMNICOTIC SAC

⦁ WATER AND NUTRITION SUPPLY TO FETUS 

⦁ DILATATION OF CERVIX

⦁ PROTECT FETUS ALLOW FETAL MOVEMONT

⦁ oligohydramnious = <200 ml at term 

⦁ polyhydramnious = >2000 ml at term