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What is Detailed survey for fetal anamolies is done at what period of gestation? and explain in detail?
Ans. is 'd' i.e., 18-20 weeks Transvaginal ultrasonography# Gestational sac and yolk sac - 5 menstrual weeks# Fetal pole and cardiac activity - 6 weeks# Embryonic movements -7 weekso Fetal gestational age is best determined by measuring the CRL between 7 and 12 weeks (variation +- 5 days).o Doppler effect of ultrasound can pick up the fetal heart rate reliably by 1 Oth week.o Routine sonography at 18-20 weeks permits a detailed survey of fetal anatomy, placental localization and the integrity of the cervical canal.