The Crown Princess gave birth to a girl Saturday afternoon, the first baby in her 8 1/2-year marriage to the Crown Prince.

The 37-year-old Crown Princess gave birth to the baby, who weighs 3,102 grams and is 49.6 cm tall, at 2:43 p.m., Hirofumi Oka, head of the General Affairs Division of the Imperial Household Agency, told a news conference at 3 p.m.

Both mother and baby are in good health, and will be able to leave the Hospital of the Imperial Household in one or two weeks, officials said. They quoted the Crown Prince as saying, "I am delighted and relieved to hear that they are both healthy . . . I plan to look after the child wishing for her happiness."

The baby is the third grandchild for the Emperor and Empress -- all of them girls. Upon hearing the news from the grand chamberlain of the Imperial household, both the Emperor and Empress looked happy and relieved, agency officials said.

In accordance with Imperial rites, the Emperor will decide on the name of the baby Dec. 7 after hearing opinions from the parents. Later Saturday, the Emperor bestowed the baby with a sword for her protection, in a ceremony meant to wish the baby a life of good health.

The Emperor said he was glad the baby had been delivered safely and thanked those in charge of the delivery for their services, while the Empress, with tears in her eyes, said she wanted to give her best wishes to the Crown Prince and Princess, according to agency officials. She also asked if the princess was well.

Prime Minister Junichiro Koizumi released a statement offering his congratulations on the birth, saying he shares his happiness with all Japanese.

The birth of a girl will likely prompt renewed debate on the possibility of revising the current male-only inheritance law to pave the way for a reigning empress, due to the lack of an immediate heir to the throne after the 41-year-old Crown Prince and his younger brother Prince Akishino.

However, Koizumi, speaking to reporters later in the day, ruled out an immediate revision to the law, saying it is too early to reach a conclusion on the issue.

The Crown Princess entered the hospital late Friday evening. She went into the second-floor delivery room at 12:40 p.m. Saturday after experiencing labor pains and gave birth to the baby about two hours later, palace officials said.

The room had been equipped with furniture and other items familiar to the Crown Princess to provide a relaxing environment during the delivery.

Accompanied by the Crown Prince, she was admitted to the hospital at 11:25 p.m. Friday after showing "signs she was ready to give birth," a palace official said.

Oka of the agency told an early morning news conference that the princess went to bed at around 1 a.m. Saturday and woke up before 7 a.m. without a noticeable change in condition.

The Crown Prince, who left the hospital at around 1 a.m. to spend the night at the nearby residence of the Emperor and Empress, returned to the hospital around 8:25 a.m.

The princess' mother, Yumiko Owada, also arrived at the hospital to be with her daughter.

After the princess checked into the hospital, officials of the Imperial Household Agency were on standby, making final preparations for celebratory events to follow the baby's birth and congratulatory books to be signed by the public.

Osamu Tsutsumi, a University of Tokyo medical professor in charge of the Crown Princess' care, and a special medical team, including doctors and nurses, oversaw the delivery of the baby.

According to the Imperial Household Agency, an event will be held from 10 a.m. today for the Emperor and Empress and the Crown Prince to receive congratulations from Imperial family members and state dignitaries such as the prime minister.

The Imperial Household Agency announced May 15 that the Crown Princess was three months pregnant.

Two traditional Shinto rites to pray for the safe delivery of the child were held separately in July and October.

The Crown Princess suffered a miscarriage in late 1999, causing her to withdraw from official engagements for several weeks until the Crown Prince's 40th birthday on Feb. 23 last year.

The baby is the third grandchild for the Emperor and the Empress. Prince Akishino, the younger brother of the Crown Prince, and his wife, Princess Kiko, have two daughters -- 10-year-old Mako and 6-year-old Kako.

Under the 1948 Imperial House Law, only a male offspring can ascend to the throne. Currently, Prince Akishino is second in line to the throne. Further down the line, the other princes -- the Emperor's uncle, his younger brother and three cousins -- are all older than the Crown Prince and Prince Akishino.

With the birth of the girl to the Crown Princess, every child born to the Imperial family since the birth of Prince Akishino in 1965 has been a girl -- from Princess Nori, 32, the only daughter of the Emperor and Empress, to Prince Akishino's daughters.