The Sun moves one degree a day and all other planets move only minutes, except the Moon, which moves one degree every two hours. So if the exact or approximate birth time is unknown, noon is used, so the Moon is no more than 6 degrees off and usually less. Not perfect, but workable. So don't miss the party because you don't know your birth time.
American hospitals usually record newborns' birth times and town halls retain them. I don't know about other countries. And a chart rectification is always an option, but it's pricey and could be wrong. Still may be worth a few comparative tries if you have money to burn. Good luck.
There are basically two kinds of BirthPrint™ (and birth chart): natal & solar.
A Natal BirthPrint™ is calculated with an exact birth time and displays the ascendant & planetary house positions. A Solar BirthPrintâ„¢ is calculated with an approximate or noon birth time, there's no ascendant and the houses are a silent backdrop. All BirthPrints™ display the Planets, Aspects & Signs.
A Natal and Solar BirthPrint™...