Jātakarma — the first hour
The popular claimThe rite for the newborn is performed before the cord is cut, and its centre is a word whispered into the ear.
The fourth of the sixteen is the first the child is present for, and the texts want it done fast — before the cord is cut, Manu says, while the child is still between two worlds.
What the sūtras prescribe
Āśvalāyana gives the sequence. The father comes to the child. He breathes on it three times. He whispers into its right ear the medhā-janana, the mantra for the birth of intelligence — May Sāvitrī, may Sarasvatī, may the Aśvins grant you wisdom — and then, with a gold ring or a gold spoon, he touches honey and ghee to the child's lips, saying that he gives it the essence of the earth and the essence of the waters. He then names the birth with the child's āyuṣya, a formula for long life, and touches the child's shoulders.
Pāraskara's version is close, with the addition of a rite for the mother's breast and a wish for the child's strength. In both, the father is the officiant. No priest is required; it is a household act.
The birth-hour
One element of the rite is easy to pass over and is the reason it sits on this site. The sūtras have the father note the nakṣatra and the muhūrta of the birth — the jātakarma is also the act of recording the birth. That recorded moment becomes the janma-kāla, the instant from which everything in a horoscope is computed: the rising sign, the Moon's nakṣatra, the daśā clock. The Bṛhat Parāśara Horā Śāstra's entire method rests on it.
This is worth saying plainly because most disputes about a chart are really disputes about this moment. A birth time recorded to the hour puts the rising sign in doubt about a third of the time; recorded to the minute, almost never. The old rite made the recording part of the ceremony, with a witness. The modern hospital record does the same job better, and a family that has the hospital's time has the one thing the rite was most concerned to preserve.
What survived
The whispered mantra survives in many families as the kān phūnknā, the breathing of a name or a syllable into the newborn's ear — and in the Muslim custom of the azān, which is a separate tradition arriving at the same gesture. The honey survives; the gold ring survives in the sonā chaṭānā of the north, gold touched to honey and to the child's tongue. What has largely gone is the fire and the Vedic text, and what has gone entirely is the idea that the father must reach the child before the cord is cut — a hospital does not wait.
The rite and the horoscope, separated
A point of honesty. The Gṛhyasūtras do not say the rite fixes the child's fate, and they do not say the horoscope does. They give a form for the first hour and ask that the hour be noted. Everything astrological is a later use of the note. A family that performs Jātakarma and never casts a chart has done what the sūtra asks; a family that casts a chart from a hospital record and never heard of Jātakarma has the moment the sūtra wanted kept. Neither has failed the other.
What this page does not say
It does not say that a child whose first hour passed without the rite lacks intelligence or length of days, and it does not say that a chart cast from a recorded hour is a prediction. It describes the rite the texts give for the first hour and explains why one part of it — the noting of the time — is the foundation of everything a horoscope does. What the hour holds is the child's.
Source — Ashvalayana Grihyasutra 1.15 and Paraskara Grihyasutra 1.16 on Jatakarma; the Manusmriti 2.29 on its timing before the cutting of the cord; the Brihat Parashara Hora Shastra on the birth-moment as the basis of the chart
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