Just search breast feeding IQ in google, you will see a lot of paper studying about IQ points related to breast feeding and it is proven IQ point is higher for breast feeding child.
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3.36 born 3.4kg
15 days 3.85kg
4.79 1 month 4.65kg
5.97 2 months 6.12kg (height 59.5cm)
6.75 4 months 7.94kg (height 65 cm)
6.5 months 8.9kg
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15 week 6 144g 20 week 5 404g
22 week 6 540g 26 week 6 1111g
28 week 2 1364g
7 week 0.66cm 8 week 6 2.06cm
9 week 6 3.03cm 12 week 6 7.05cm