The Domestic Sutras of Gobhila

Soma enjoys the girl who shows signs of youth; Gandharva enjoys the one with developed breasts; and Agni enjoys the one who has reached menstruation || 18 || This traditional verse suggests that a girl passes through the guardianship of various deities as she matures before being ready for a human husband. Therefore, a girl who lacks the signs of youth, has no menstrual cycle, has undeveloped breasts, and has not yet passed through these stages of divine protection is not considered ideal for marriage. These are the words of the Grihyasangraha (2.97-98). Furthermore, the primary medical text, the Sushruta Samhita, states:

"From the essence of food, the blood known as menses arises in women. It begins after the age of twelve and begins to decline at fifty." original Sanskrit: rasadeva striya raktam raja samjnam pravartate... — Sushruta Samhita, Chapter 14

This means that after twelve years, a girl’s menstrual cycle begins, and it starts to wane after fifty. Furthermore:

"A wise father should count his daughter's seasons [menstrual cycles]. He should carefully protect the girl at home during her periods for a fixed number of days." || 1 ||

This means that a father should count his daughter’s menstrual cycles from the very beginning. There is a regulation for how many cycles a girl must remain in the home; once she has reached that number of cycles, her marriage should then take place. It should never be done before this; on the contrary, if it happens later, it is even better.

Regarding the question of when a bride and groom should marry according to scripture and logic, the late and renowned scholar of Varanasi, the Great Teacher original: Mahamahopadhyaya — a title for an eminent scholar Pandit Ramamishra Shastri, writes the following in the preface of his book, Investigation into the Time of Marriage:

PREFACE

At the present time, in various parts of India among those who profess to be followers of the Vedic religion and practices, the custom of marrying girls in mere infancy is a common one, and people think that if they do not conform to this custom they incur sin. But the truth is that the rule about the infant marriage of girls enjoined in the Dharmashastras Dharmashastras: Ancient Indian law books and legal treatises on duty and social conduct. is not what is called nitya (a fixed and obligatory duty, the non-performance of which is a sin) but kamya (optional and to be performed only through the desire of obtaining some particular benefit). The principal age for marriage is that of twelve and upwards as clearly declared by Manu; only it is necessary that the marriage ceremony should take place before the age of puberty is...