Both parents and those without children oppose the use of the word 'childless' in a report by the US Pew Research Center, because they feel that it implies a deficit or disability. Some people who choose not to have children would prefer the term 'childfree'. However, people who would like to have a child but cannot, as well as many parents, object to the 'free' of 'childfree', feeling that it implies that children are a bind, or something negative. Someone has suggested that the word 'non-mom' is a good compromise, but there are a few problems with that. What about dads, for one thing? Also, in the UK we would have to say 'non-mum', as we don't say 'mom' here, and that doesn't have quite the same ring about it.
Dictionary definitions generally do not imply a deficit or anything negative about the suffix -less. Here are the two OED definitions:
Childless: Having no child or children; without offspring
Child-free: Designating or characteristic of a person who does not have children, esp. by choice
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