The child, Jennalyn Sentino, was one of 100 babies born in state hospitals all over the archipelago who received the symbolic designation of "100,000,000th baby".
"This is both an opportunity and a challenge... an opportunity we should take advantage of and a challenge we recognise," Juan Antonio Perez, executive director of the official Commission on Population, told AFP.
While a growing population means a larger workforce, it also means more dependents in a country where about 25% of people are living in poverty, he said.
He said the Philippines had to find a way to bring services to the poorest families while also lowering the average number of children that fertile women will bear in their lifetimes.
"We'd like to push the fertility rate down to two children per (woman's) lifetime," from the current level of an average of three per woman, he said.
While celebrating the birth of the babies with cake and gifts of clothing and blankets, the government will also monitor each of the designated 100 children over the coming years to see if they are receiving the required health services, Mr Perez added.
Jennalyn's father, 45-year-old van driver Clemente Sentino, said he was grateful for the government aid, but expressed confidence he could support his child and his partner.
He and the child's mother, Dailin Cabigayan, 27, are not yet married. "She just happened to get pregnant. But we do have plans to get married," he told AFP.
"I make just enough to get by but at least my job pays regularly. We will find a way to make it fit," he said.
Efforts to control the Philippines' population growth have long been hampered by the influence of the Roman Catholic Church, which counts about 80% of Filipinos as followers and which disapproves of all forms of artificial birth control.
It was only in April that the government finally overcame over a decade of Church opposition to implement a reproductive health law providing the poor with birth control services.
Mr Perez said with the law's implementation, about two to three million women who previously did not have access to family planning now do.
Meanwhile, Father Melvin Castro, head of the commission on family and life of the country's Catholic bishops, was quoted by a church-run radio station as praising the ballooning population, as there would be more "young workers" to power the economy.
President Benigno Aquino's spokesman Herminio Coloma said the milestone showed the importance of making "the right investments in people".
The government had prepared for this by spending more on "human development", particularly education, he told reporters.
Meanwhile, Klaus Beck, country representative of the United Nations Population Fund, endorsed the Philippines' new focus on family planning in a statement issued to coincide with the population landmark.
"Governments that are serious about eradicating poverty should also be serious about providing the services, supplies, information that women, men and young people need to exercise their reproductive rights," he said.