Thank you Thank you

The Maharil writes the reason we say at a Bris, "Hodu
Lashem  Ki Tov*", twice, 

is because the Gemoro says Arbo'o Tzrichin L'Hodos.

(Four people who were saved need to thank Hashem)

One of the four who needs to thank is someone who gets out of
prison. The baby coming out of the mother's womb is like coming out of prison. 

The second Hodu is for the Mother who was sick during childbirth