I'd think that when feeding a toddler her breast tissue is going to be pretty much baseline right now. After all, lactation is the normal state of breasts, but the glands won't be as active as in the stages of full lactation.
As for a mammo taken just for the purpose of having a starting point: Is she at risk for breastcancer ? then taking mammo's will probably be fine, but weaning will not. If she's not at increased risk why bother to raising the risk by both adding radiation to the breast and wean from a preventive measure?

Warmly,

Gonneke, IBCLC in PP, LC lecturer, skeptical-practical thinker in southern Netherlands

--- On Mon, 1/3/11, Jessica Lang Kosa <[log in to unmask]> wrote:

From: Jessica Lang Kosa <[log in to unmask]>
Subject: Re: [LACTNET] weaning before baseline mammogram
To: [log in to unmask]
Date: Monday, January 3, 2011, 8:46 PM

To clarify, I think she is persuaded that she should not rush the weaning.  Her question now is more "Once I stop weaning, how long should I wait before having the mammogram, so that it's most readable and reliable as a baseline?"

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