I remember in antenatal classes the teacher told us that the cervix dilates to exactly 10cm, as the baby's head has a diameter of 9.5cm.
Why, then, does my red book show a centile variation of between 32 and 39cm head circumference at birth. I can't remember the maths to work it out (2xPixR or PixRxR or something?) Surely if there's a variation in circumference then there's also a variation in diameter.
Does this mean that some cervixes dilate further than 10cm, or do some baby heads have to squish more as they pass through, or is 10cm the maximum diameter a head will be, and smaller ones just slip through?
I'm hoping someone can work out the maths and explain - this has been puzzling me for a while!!!!!
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Childbirth
A technical question about heads.....
9 replies
CuppaTeaJanice · 26/10/2008 17:46
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