Etiquette and Timing of Lovemaking
There is very important advice that Rasulollah (S) has given to Imam Ali (AS) which has significant outcomes, and this is given below in full.
As can be seen from the following hadith, the date and time of the intercourse and therefore conception has a direct and defining impact on the character of the child conceived.
(A) Dates and times when lovemaking is Makruh (undesirable)
1. Do not have intercourse with your wife on the First, Middle, and Last day of the (lunar) month, for it will hasten mental illness and leprosy for her and her child.
2. Do not have intercourse with your wife in the after noon, for if a child were conceived at that time, s/he would be cross-eyed, and the Shaytaan is pleased when a human is cross-eyed.
3. Do not speak while lovemaking, for if a child were conceived, he would not be immune from being dumb.
4. One should not look into his wife's vagina for this brings about blindness (in the child).
5. Do not make love with your wife with the desire of and lust for another woman (in your mind), for I fear that if a male child were conceived at that moment he would be Mukhannath (one who desires other men to have sex with him), effeminate, and stupid.
6. One who is in the status of Junub in bed with wife should not read the Qur'an for I fear that fire might descend upon them and burn them.
7. Do not make love unless each of you has a piece of cloth to clean yourselves with. For if you use the same cloth, enmity would befall between you and this brings about separation and divorce.
8. Do not have intercourse with your wife standing up, for this is the conduct of the donkey, and if a child were conceived (in that state) s/he would urinate in bed, just as the donkey urinates everywhere.
9. Do not make love with your wife on the eve of Eid-ul-Fitr, for if a child were conceived as a result, that child would not be but evildoer.
10. Do not make love with your wife on the eve of Eid-ul-Adhha (Eid-e-Qurban), for if a child were conceived as a result, that child would have either six fingers or four.
11. Do not make love with your wife under a fruit-bearing tree, for if a child were conceived as a result, s/he would be torturer, or a murderer or a spy (for an oppressive government against the Mu'minin.)
12. Do not make love with your wife under direct sunshine, unless you set up a screen to cover you up, for if a child were conceived as a result, s/he will continue to live in poverty until s/he dies.
13. Do not make love with your wife between the Athaan and the Iqamah, for if a child were conceived as a result, s/he would be eager to shed blood.
14. If your wife were pregnant, do not make love with her unless you have Wudhu, otherwise the child would be blind-hearted and stingy.
15. Do not make love with your wife on the eve of mid-Sha'baan, for if a child were conceived as a result, the child would be disfigured with large spots on his face.
16. Do not make love with your wife if there were two days left to the (lunar) month, for if a child were conceived as a result, s/he would be ‘Ashshaar (inspector/collector of tax (which is illegal from the Islamic point of view)), or an assistant to the oppressor, and many people would perish at their hands.
17. Do not make love with your wife on the roof top of a building, for if a child were conceived as a result, s/he would be hypocrite, showoff, and commit Bid'ah.
18. If you have travelled, do not make love with your wife on that night, for if a child were conceived as a result, s/he would give his/her money in a false way, [then Rasulollah (S) recited] {Verily the spendthrifts are the brothers of the Satans.} (17:27).
19. Do not make love with your wife if you are on a journey of three days and nights, for if a child were conceived as a result, s/he would be helper and assistant to ever oppressor.
(B) Dates and times when lovemaking is Mustahab (desirable)
1. O Ali! You are highly encouraged to make love on the eve of Monday, for if a child were conceived, s/he would be a memoriser (Hafiz) of the Book of Allah, and pleased with whatever Allah has bestowed upon him/her.
2. If you make love with your wife on the eve of Tuesday and a child were conceived, s/he would be bestowed the Martyrdom, after the declaration of “There is no god but Allah, Muhammad is Rasulollah”, and Allah would not punish him with the polytheists. Her/his mouth would smell pleasant, s/he would be kindhearted, generous and freehanded, her/his tongue would be pure from backbite, lie, and accusation.
3. If you make love with your wife on the eve of Thursday and a child were conceived, s/he would be one of the rulers, or one of the scholars.
4. If you make love with your wife on Thursday when the sun passes the middle of the sky (after noon), and a child were conceived, s/he would be less prone to the temptations of the Shaytaan. S/he would be intelligent and Allah Exalted and Praised is He would bestow upon her/him health and safety in the Deen and the material life.
5. And if you make love to your wife on the eve of Friday, and there were a child conceived, s/he would be an eloquent lecturer / preacher.
6. And if you make love to your wife on Friday afternoon, and there were a child conceived, s/he would be a renowned scholar.
7. And if you make love to your wife on the eve of Friday, after the ‘Eshaa' and there were a child conceived, it is hoped that InSha'Allah s/he would be one of the ABDAAL (i.e. those pious individuals that the earth is never without one, if one of them dies another would replace him.)
8. Do not make love to your wife during the first hour of the night, for if there were a child conceived, it is feared that s/he would be a sorcerer, swindler who prefers this world to the hereafter.
Remember and keep this advice from me, just as I have remembered and kept it from my brother Jibra'il.”
ImamShirazi.com