Japan's Princess Kiko gave birth on Wednesday to a baby boy -- the first male heir to be born into the ancient imperial family in more than four decades. The birth of a boy, who will be third in line after his uncle and his father, will likely dampen debate on letting women inherit the throne -- an idea opposed by conservatives eager to preserve a tradition they say stretches back more than 2,000 years.An Imperial Household Agency official told reporters Kiko had given birth by a Caesarean operation to the 2,558 gram (5 lb 10 ounce) boy at 8:27 a.m. (2327 GMT). He said both Kiko, 39, and the baby were doing well. The birth took place at the private Aiiku Hospital, which has close ties to the royal family and has seen many celebrity births in the past.