The major contribution of the amniotic fluid after 20 weeks of gestation
Amniotic fluid: - * pH = 7.1 -7.3 * Specific gravity= 1.008-1.010 * Osmolality = 250 mOsm/L * Rate of amniotic fluid turnover is 500cc/hr * Completely changed and replaced in every 3 hours * Main source- fetal urine (overall) * Main source after 20 weeks- fetal urine Ref:- Mudaliar and Menon's 12th Edition; Pg num:- 28.
Fetal lung fluid
Fetal skin
Ultrafiltrate and maternal plasma
Fetal urine
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