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Garbhadhan, a compound Sanskrit word, means conception, impregnation or insemination. It is the first of the sixteen Vedic Samskaras and is meant to be performed by man and woman at an auspicious time and date for the sake of begetting the desired child. In Hindu astrology this term is used in connection with Nisheka or consummation of marriage. B.Suyanarain Rao in his commentary on Chapter IV of Brihat Jataka explains that the health of women, and thus the health of the community, depends upon the auspicious planetary influences exerted during the act of sexual union; every male or female must come through a female, and therefore, woman occupies the highest rank in the order of creative agencies. The act of sexual union resembles the nature of the 7th house from the sign rising at the time of union or query; if evil planets occupy or aspect the 7th, then the act will be conducted in a quarrelling mood, but when benefics aspect or join the 7th the union takes place under very pleasant circumstances.
A woman becomes capable of bearing a child after appearance of the first of the menses recurring in a cycle found to be governed by the Moon and Mars. When the Moon is in an anupchayasthana i.e. in a kendrasthana or a trikonasthana or in the 2nd or the 12th from its natal position, the menses for conception occurs but if the Moon is in an upachayasthana i.e. in the 3rd, the 6th, the 10th or 11th,and receives the aspect of a masculine benefic planet the woman gets sexual union with man but does not conceive. If the Sun, the Moon, Venus and Mars occupy their own navamsas and Jupiter is in the lagna-kendra or in a trikonasthana, conception takes place. Bhattotpala citing Saravali (Slokas VIII. 2-4) in his commentary adds that a potent woman can become pregnant when at the time of commencement of the regular menses the Moon aspected by Mars is not in an upachayasthana from the Janam-rasi i.e. from the natal position of the Moon; if the Moon is aspected by Mars or is in an upachayasthana then she will not conceive.
The woman born with the Moon occupying Taurus, Virgo, Scorpio or Leo sign gives birth to few sons; the woman who has Jupiter or Venus in the 8th house at the time of her birth suffers miscarriages or still-births; the woman whose 7th house from the lagna is formed by an evil sign or evil planet/s aspect the 7th house will not bear any issue she will be barren. Either Mercury or Saturn occupying the 7th makes a woman barren or who marries a person who is impotent, or is herself diseased.
If the Moon aspected by Jupiter is in an upachayasthana from the Janam-rasi of man or if a friendly benefic or Venus aspects, he can get a woman become pregnant.
A woman can conceive three days after the appearance of menses till the 16th day. If the Sun, the Moon, Mars and Venus are in their own navamsas and Jupiter aspects the Lagna know that pregnancy has occurred provided the moment of conception is afflicted by adverse Tithi, Gandanta etc; or by the Moon occupying an unfavourable nakshatra, or the lagna rising at that moment is not afflicted by malefics and ill-placed benefics.
If the woman conceives -
• on the 4th night she will bear a short-lived son, • on the 5th night she will bear a daughter, • on the 6th night a son who will expand the family, • on the 7th night a barren daughter, • on the 8th night a son, • on the 9th night a beautiful daughter, • on the 10th night an influential high-ranking son, • on the 11th night a wretched ugly daughter, • on the 12th night a wealthy son, • on the 13th night an evil-minded and disgraceful daughter, • on the 14th night a dutiful and noble son, • on the 15th night a wealthy and a fortunate daughter, and • on the 16th night, a learned and an intelligent son.Here, night includes day-time. People are seldom aware of the exact time of conception, therefore, traditionally these and other relevant planetary combinations a few cited hereat if found present in the prasna-charts are taken to indicate same results. If at the time of commencement of menses the lagna for that moment is aspected by Mars the woman will have sexual union with an evil person; if aspected by the Sun, with a noble ruler and if aspected by Saturn, with a servant. She will have a safe and pregnancy in case benefics influence the lagna, the Moon and the trines and the quadrants or if malefic are in the 3rd or the 11th aspected by the Sun.
Varahamihira states that powerful lagna, The Sun, the Moon and Jupiter situated in odd signs or navamsas cause masculine birth, in even signs and navamsas feminine birth or if Jupiter and the Sun are in odd signs then a male is born, if Venus, Mars and the Moon are in even signs, a female is born; Saturn occupying odd signs from the lagna excepting the lagna causes male birth. He has also given yogas indicating birth of eunuchs.