Yes, yes, yes ... but in the spiritual world despite having sexual activity there is no pregnancy.
Very different from this material world, where you must use very low methods to prevent pregnancy, such as orgasm without ejaculation, condoms, contraceptives and abortion.
"Practically speaking, there is no sex life in the spiritual world, but even if sometimes it does occur, there is no pregnancy at all." (Srila Prabhupada - SB 5.17.12)
"Three parts of His body are short: His neck, thighs and genitals." (NOD 21 - Qualities of Śrī Kṛṣṇa)
And therefore in kali yuga nor vanaprastha and nor sannyasa.
Grhastha until the last breath. Is it then?
SB 11.18.43
brahmacaryaṁ tapaḥ śaucaṁ
santoṣo bhūta-sauhṛdam
gṛhasthasyāpy ṛtau gantuḥ
sarveṣāṁ mad-upāsanam
"A householder may approach his wife for sex only at the time prescribed for begetting children. Otherwise, the householder should practice celibacy, austerity, cleanliness of mind and body, satisfaction in his natural position, and friendship toward all living entities. Worship of Me is to be practiced by all human beings, regardless of social or occupational divisions."
The words of Krsna Himself.
So now, who is my wife? Who is my husband? I've already had thousands of wives in countless lives and had to detach myself from all of them.
"Everyone has abandoned me, seeing me as penniless,
Wife, relatives, friends, brothers, everyone.
This is misery, but it gives me a laugh. I sit alone and laugh.
In this māyā-saṁsāra, whom do I really love?
Where have all my loving father and mother gone to now?
And where are all my elders, who were my own folk?
Who will give me news of them, tell me who?
All that is left of this family life is a list of names."
"Like the froth on the sea water mixes again in the sea,
Māyā’s saṁsāra’s play is just like that.
No one is mother or father, or personal relative,
Just like the sea-foam they remain but a short time,
Just as the froth on sea water mixes again in the sea,
The body made of five elements meets with destruction.
How many bodies does the embodied soul take in this way;
His relatives are all simply related to this temporal body."
Undoubtedly the love for all who have departed or are elderly remains. But in the last stage of life a person focuses his attention on Radha Krishna. This is the purpose of vanaprastha and sannyasa. They are elderly.
Already passed the stage of kama sutra
SB 1.13.18 — Mahātmā Vidura knew all this, and therefore he addressed Dhṛtarāṣṭra, saying: My dear King, please get out of here immediately. Do not delay. Just see how fear has overtaken you.
SB 1.13.19 — This frightful situation cannot be remedied by any person in this material world. My lord, it is the Supreme Personality of Godhead as eternal time [kāla] that has approached us all.
SB 1.13.20 — Whoever is under the influence of supreme kāla [eternal time] must surrender his most dear life, and what to speak of other things, such as wealth, honor, children, land and home.
SB 1.13.21 — Your father, brother, well-wishers and sons are all dead and passed away. You yourself have expended the major portion of your life, your body is now overtaken by invalidity, and you are living in the home of another.
SB 1.13.22 — You have been blind from your very birth, and recently you have become hard of hearing. Your memory is shortened, and your intelligence is disturbed. Your teeth are loose, your liver is defective, and you are coughing up mucus.
SB 1.13.23 — Alas, how powerful are the hopes of a living being to continue his life. Verily, you are living just like a household dog and are eating remnants of food given by Bhīma.
SB 1.13.53 — On the banks at Saptasrota, Dhṛtarāṣṭra is now engaged in beginning aṣṭāṅga-yoga by bathing three times daily, in the morning, noon and evening, by performing the Agni-hotra sacrifice with fire and by drinking only water. This helps one control the mind and the senses and frees one completely from thoughts of familial affection.
SB 1.13.54 — One who has controlled the sitting postures [the yogic āsanas] and the breathing process can turn the senses toward the Absolute Personality of Godhead and thus become immune to the contaminations of the modes of material nature, namely mundane goodness, passion and ignorance.
SB 1.13.55 — Dhṛtarāṣṭra will have to amalgamate his pure identity with intelligence and then merge into the Supreme Being with knowledge of his qualitative oneness, as a living entity, with the Supreme Brahman. Being freed from the blocked sky, he will have to rise to the spiritual sky.
SB 1.13.56 — He will have to suspend all the actions of the senses, even from the outside, and will have to be impervious to interactions of the senses, which are influenced by the modes of material nature. After renouncing all material duties, he must become immovably established, beyond all sources of hindrances on the path.
SB 1.13.57 — O King, he will quit his body, most probably on the fifth day from today. And his body will turn to ashes.
