SB 3.31.1

श्रीभगवानुवाच
कर्मणा दैवनेत्रेण जन्तुर्देहोपपत्तये ।
स्त्रियाः प्रविष्ट उदरं पुंसो रेतःकणाश्रयः ॥१॥

Text

śrī-bhagavān uvāca
karmaṇā daiva-netreṇa
jantur dehopapattaye
striyāḥ praviṣṭa udaraṁ
puṁso retaḥ-kaṇāśrayaḥ

Synonyms

śrīplugin-autotooltip__small plugin-autotooltip_bigsri

and opulence; beautiful; beauty; fortune; Lakṣmī, the goddess of fortune; named //śrī//; opulence or beauty; opulences; the affluent; the goddess of fortune; the goddess of fortune, or a beautiful calf; the treasury houses; transcendental; with opulence.
-bhagavānplugin-autotooltip__small plugin-autotooltip_bigbhagavan

my dear Lord; my lord; O exalted sage; O godly personality; O great //brāhmaṇa//; O great sage (Śukadeva Gosvāmī); O great sage; O great saint; O great soul; O Lord; O Lord, Supreme Personality of Godhead; O most powerful; O most powerful devotee; O most powerful sage; O my Lord; O my lord, O great one; O Personality of Godhead; O possessor of all opulences; O powerful one; O Supreme; O Supreme Lord; O Supreme Lord, O Personality of Godhead; O Supreme Personality of Godhead; O supremely powerful one; O worshipful sage; O Your Lordship; the Personality of Godhead.
uvācaplugin-autotooltip__small plugin-autotooltip_biguvāca

answered; described; explained; he recited; he said; inquired; prayed; replied; said; she said; she spoke; spoke; talked with them.
—the Supreme Personality of Godhead said; karmaṇāplugin-autotooltip__small plugin-autotooltip_bigkarmaṇā

activities; by activities; by deeds; by destiny; by fruitive activities; by occupation; by performing ritualistic activities according to the //Vedas//; by such activities; by the acts of; by the performance; by the result of work; by the touch of his hand; by their activities; by their activity; by their behavior; by work; therefore by your fruitive reaction; whose activities; with your activities.
—by the result of work; daivaplugin-autotooltip__small plugin-autotooltip_bigdaiva

by destiny; by providence; by the authority of the Lord; by the grace of the Lord; by the Lord; by the Supreme Personality of Godhead; destiny; divine; providence; superhuman; supernatural; the demigods; transcendental.
-netreṇaplugin-autotooltip__small plugin-autotooltip_bignetreṇa

under the supervision of the Lord.
—under the supervision of the Lord; jantuḥplugin-autotooltip__small plugin-autotooltip_bigjantuḥ

fetus; living being or animal; living entity; the child; the living being; the living entity; unintelligent living beings like animals.
—the living entity; dehaplugin-autotooltip__small plugin-autotooltip_bigdeha

a body; apply; bodies; body; deliver; expansion of the body; give; give Me; in the body; kindly award; kindly give; kindly give it to me; My body; of a material body; of the body; of this body; offer; please award; please give; the body; the gross body and subtle mind; the gross material body; the material body; the spiritual body; this body; with the body; You give; you put.
—a body; upapattayeplugin-autotooltip__small plugin-autotooltip_bigupapattaye

for obtaining; for the attainment.
—for obtaining; striyāḥplugin-autotooltip__small plugin-autotooltip_bigstriyah

all the queens; all the women, the //gopīs//; all women; also other ladies of the palace; females; heavenly society women; illicit association with women; ladies; the //gopīs//; the beautiful damsels; the damsels; the ladies; the wives; the women; the young girls; wives; wives or other women; women (the Apsarās); women.
—of a woman; praviṣṭaḥplugin-autotooltip__small plugin-autotooltip_bigpravistah

after entering; entered; entered in; entered into; entering; entering among; enters; has entered; having entered; having entered into; He entered; thus being entered.
—enters; udaramplugin-autotooltip__small plugin-autotooltip_bigudaram

abdomen; His abdomen; His belly; stomach; the abdomen; the abdomen*; the belly (for various types of food); the body; the stomach; the womb; waist.
—the womb; puṁsaḥplugin-autotooltip__small plugin-autotooltip_bigpuṁsaḥ

a person; by the Supreme Personality of Godhead; of a human being; of a living entity; of a male; of a man; of a person; of any person; of every human being; of everyone; of Lord Viṣṇu (Garbhodakaśāyī Viṣṇu); of man; of one who is so engaged; of the //puruṣa-avatāras//; of the gigantic form; of the great personality; of the human being; of the living being; of the living entities; of the living entity; of the Lord; of the man; of the person; of the Personality of Godhead; of the persons; of the plenary portion, Lord Viṣṇu, the expansion of Lord Kṛṣṇa; of the puruṣa-avatāras; of the Supreme; of the Supreme Person; personality; Personality of Godhead; Supreme Personality of Godhead; than a person; the people in general; the Personality of Godhead; their husbands; to a person; with a person.
—of a man; retaḥplugin-autotooltip__small plugin-autotooltip_bigretah

of semen; semen; semen of birth; the semen.
—of semen; kaṇaplugin-autotooltip__small plugin-autotooltip_bigkana

a fragment; a particle; broken rice; drop; fragment; fragmental portion; particle; particles; small particle.
—a particle; āśrayaḥplugin-autotooltip__small plugin-autotooltip_bigasrayah

depending on; dwelling in; endowed with; object of; of the shelter; one who has taken shelter; reservoir; resort; shelter; the //summum bonum//; the basis; the master; the original foundation; the support; the ultimate shelter, the Supreme Personality of Godhead.
—dwelling in. 

Translation

The Personality of Godhead said: Under the supervision of the Supreme Lord and according to the result of his work, the living entity, the soul, is made to enter into the womb of a woman through the particle of male semen to assume a particular type of body. 

Purport

As stated in the last chapter, after suffering different kinds of hellish conditions, a man comes again to the human form of body. The same topic is continued in this chapter. In order to give a particular type of human form to a person who has already suffered hellish life, the soul is transferred to the semen of a man who is just suitable to become his father. During sexual intercourse, the soul is transferred through the semen of the father into the mother’s womb in order to produce a particular type of body. This process is applicable to all embodied living entities, but it is especially mentioned for the man who was transferred to the Andha-tāmisra hell. After suffering there, when he who has had many types of hellish bodies, like those of dogs and hogs, is to come again to the human form, he is given the chance to take his birth in the same type of body from which he degraded himself to hell. 

Everything is done by the supervision of the Supreme Personality of Godhead. Material nature supplies the body, but it does so under the direction of the Supersoul. It is said in Bhagavad-gītā that a living entity is wandering in this material world on a chariot made by material nature. The Supreme Lord, as Supersoul, is always present with the individual soul. He directs material nature to supply a particular type of body to the individual soul according to the result of his work, and the material nature supplies it. Here one word, retaḥ-kaṇāśrayaḥ, is very significant because it indicates that it is not the semen of the man that creates life within the womb of a woman; rather, the living entity, the soul, takes shelter in a particle of semen and is then pushed into the womb of a woman. Then the body develops. There is no possibility of creating a living entity without the presence of the soul simply by sexual intercourse. The materialistic theory that there is no soul and that a child is born simply by material combination of the sperm and ovum is not very feasible. It is unacceptable.