Question: How common was it for births to be registered in the newspapers in the 18th century?
Answer: From my experience the notices of marriages and deaths were more common in the 18th century. The occasional birth of a notable from Europe, or extreme multiple births are listed. As a member of NEHGS you have access to early 18th century newspapers by using our External Databases: http://web1.americanancestors.org/external-databases/ If you have any questions on using Early American Newspapers please let me know onlinegenealogist@nehgs.org