Fetus 1 Flashcards
Definition of Fetal Growth Period.
Calculated from day of Ovulation/Fertilisation.
i.e D14 of cycle.
Not D1 of pregnancy
Cardiac Activity is seen at
5th week of preg or 3rd week after fertilisation.
Name the Three Fetal Growth periods.
1) Fertilised ova- upto 4 wks of preg.
2) Embryonic period - 5 - 10 wks of preg.
3) Fetal Period - 11 wks till Delivery.
Most teratogenic period of pregnancy
1st trimester.
1st Trimester
uptil 13 wks + 6 days
2nd Trimester
14 weeks til 27 wks + 6 days.
3rd Trimester
28 wks till 40 wks.
Clinical assessment by Fundal Height.
1) 12 wks
2) 16wks
3) 20 wks
4) 24 wks
5) 28 wks.
6) 32 wks.
7) 36 wks.
8) 40 wks.
1) Pubic symphysis
2) Midway btw Pubis symphysis and Umbilicus
3) Lower border of umbilicus
4) Upper border of umbilicus
5) 1/3 btw Xiphisternum and umbilicus
6) 2/3 btw xiphisternum and umbilicus
7) Xiphisternum.
8) due to dragging down again at the level of 2/3 btw xiphisternum and umbilicus.
What is Lightening or welcome sign.?
lower of height of uterus at 40 weeks to the level of 2/3 btw xiphisternum and umbilicus thereby decreasing the maternal resp discomfort.
First trimester Fetal age estimation Best parameter
Crown rump length
Second trimester Best parameter for estimation of fetal age
Biparietal diameter> Head circumference
Third trimester Best parameter for age estimation
Femur length
CRL
Crown rump length
From vertex to coccyx
CRL + 6.5mm
GA in wks
CRL + 42
GA in days
Missed abortion signs via CRL
If CRL > 7 mm with no cardiac activity
BPD
Outer table of one side to be inner table of fetal skull on the other side
Best parameter for age assessment in second trimester
HASSE rule
<5 m = Square root of fetal length = GA
>5 m= Fetal length by 5 =GA
Crown heel length
Vertex to Heel length in fetus above 5 m of age
Clinical assessment of Wgt of fetus
Johnson formula
USG assessment of Fetal wgt
Shepherd or Hadlock formula
Parameter for USD assessment of fetal growth
Abdominal circumference
Plane of measurement of abdominal circumference in USG
Measured in a plane where portal sinus, Umbilical vein and fetal stomach must be visible.
Only parameter that indicates IUGR and macrosomia
Abdominal circumference
Criteria for macrosomia in abdominal circumference length
Greater than 35 cm
Normal ratio of Femoral length and abdominal circumference
20 to 40%
Site of fetal haematopoiesis until six weeks of pregnancy
Yolk sac
Haemoglobin formed by yolk sac
Gower one and two
Portland Hb
Site of Haematopoiesis until 20 weeks
Liver
Site of haematopoiesis after 20 weeks
Bone marrow
Hb F is formed in
Liver - upto 20 wks
Site of formation of haemoglobin A
Bone marrow – after 20 weeks
Fetal RBC’s are 
Nucleated and Macrocytic
At time of birth, Hb concentration
16-18g/dl
% of Hb F and HbA at birth
Hb F = 75-80%
Hb A= 20-25%
Higher affinity for oxygen
HbF
Which Hb Resistant to acid or alkali
Hb F
Kleihauer betke test
Diff btw Fetal RBC and maternal RBc
Acid elution test reagent.?
Citric acid phosphate buffer
How to calculate Anti D in RH negative female.!?
Acid elution or Kleihauer betke test
Fetal gross body movements
Seven weeks
Testis formation
Seven weeks
Ovary formation
Eight weeks
Glucagon synthesis
Eight weeks
Internal genitalia
10 weeks
Breathing movements
11 Weeks
Female external genitalia
12 weeks
Male external genitalia
14 weeks
Insulin production
14 weeks
H-P axis
12 weeks
Fetal urine production
12 weeks
Meconium production
16 wks
Fetal Ig M production
20 wks
Ig G to fetus at
16 wks
Surfactant production
20 weeks
