Short answer. For civil purposes, Article 41 of the Civil Code treats a foetus as born if it is alive when completely delivered from the mother's womb. But if it had an intra-uterine life of less than seven months, it is deemed born only if it survives at least twenty-four hours after complete delivery.
What the law says
For civil purposes, the foetus is considered born if it is alive at the time it is completely delivered from the mother's womb. However, if the foetus had an intra-uterine life of less than seven months, it is not deemed born if it dies within twenty-four hours after its complete delivery from the maternal womb.
Civil Code, Article 41 — When a Foetus Is Considered Born. Read the full provision →
The general rule
The law needs a clear test for when a newborn counts as a person for civil matters like inheritance and donations. Article 41 of the Civil Code supplies it. As a rule, the foetus is considered born if it is alive at the time it is completely delivered from the mother's womb. Two conditions must both be met: the child must be completely delivered, fully separated from the mother, and it must be alive at that moment. If both are satisfied, the child is treated as born for civil purposes and can, for example, acquire and transmit rights, even if life turns out to be only momentary.
The exception for very premature births
There is one important qualification for babies born very early. The article continues: However, if the foetus had an intra-uterine life of less than seven months, it is not deemed born if it dies within twenty-four hours after its complete delivery from the maternal womb. So for a foetus carried less than seven months, being alive at delivery is not enough on its own. It must also survive for a full twenty-four hours after complete delivery. If such a very premature child lives at least twenty-four hours, it is considered born; if it dies within that first day, the law treats it as never having been born for civil purposes.
Why the rule matters
This is not a merely academic distinction. Whether a child is "considered born" can decide questions of inheritance and property. For instance, a child who is considered born, even briefly, may inherit from a parent and then transmit that inheritance to its own heirs, changing who ultimately receives the estate. The same can affect donations made in favor of an unborn child. Because large consequences can turn on minutes or hours, Article 41 draws firm lines: the ordinary test for full-term births, and the stricter twenty-four-hour test for those with less than seven months of intra-uterine life.
What the article is and is not about
It is worth being clear about the article's scope. It speaks to civil personality, whether a child is a person capable of holding civil rights, and it works together with the rule that a conceived child is given a limited, provisional personality for purposes favorable to it. The article is not a statement about criminal responsibility or about abortion, which other laws govern. Its job is narrow but important: to tell courts and families, when an estate or a gift is at stake, whether a child who lived only a short time after delivery is legally regarded as having been born.