The Quran contains the following well-known passage, which appears to speculate on where a man's seed originates:
Surah 86:5-7
5 Let people then consider what they were created from!
6 ˹They were˺ created from a spurting fluid,
7 stemming from between the backbone and the ribcage.
There is only one "spurting fluid" which is involved in reproduction, and it does not come from "between the backbone and the ribcage". It appears Muhammad identified semen formation somewhere in the torso, near the spine, rather than the testes. Bolstering this, there is a narration in which Allah uses "while you were in the backbone of Adam" (Sahih al-Bukhari 3334) as a euphemism for "before you were born".
Of this infamous passage in the Quran, Ibn Kathir (1373 AD) says:
Tafsir Ibn Kathir - Surah 86:6-7
Then Allah says, (He is created from a water gushing forth.) meaning, the sexual fluid that comes out bursting forth from the man and the woman. Thus, the child is produced from both of them by the permission of Allah.
Due to this Allah says, (Proceeding from between the backbone and the ribs.) meaning, the backbone (or loins) of the man and the ribs of the woman, which is referring to her chest. Shabib bin Bishr reported from `Ikrimah who narrated from Ibn `Abbas that he said, (Proceeding from between the backbone and the ribs.) "The backbone of the man and the ribs of the woman. It (the fluid) is yellow and fine in texture. The child will not be born except from both of them (i.e., their sexual fluids)."
Ibn Kathir understands this to refer to seminal fluid, and even narrates a Hadith stating that it refers to a woman's "discharge" as well, which will be covered in the next section of this article. This is mentioned for the sake of Muslims who would wish to say the "fluid" refers to something else, when the context makes that impossible, and that is not how Muslims historically understood this passage.
Muhammad also seemingly taught that women have a reproductive "discharge" like unto a man's semen, which was "thin (low viscosity) and yellow":
Sahih Muslim 311
Anas b. Malik reported that Umm Sulaim narrated it that she asked the Messenger of Allah (ﷺ) about a woman who sees in a dream what a man sees (sexual dream). The Messenger of Allah said:
In case a woman sees that, she must take a bath. Umm Sulaim said: I was bashful on account of that and said: Does it happen? Upon this the Messenger of Allah (ﷺ) said: Yes (it does happen), otherwise how can (a child) resemble her? Man's discharge is thick and white and the discharge of woman is thin and yellow; so the resemblance comes from the one whose genes prevail or dominate.
This is also narrated in Sahih al-Bukhari 130, 3328, 6091, and Sahih Muslim 313a, 314b.
Notice the following about the above:
This second point is completely incorrect. Women do not have wet dreams like men, during which they have a thin and yellow discharge which has genetic material in it. This is indisputably false.
Muhammad was also asked, as a test of his prophethood, what determines whether a child resembles its father or its mother. His answer, which he claimed came directly from God, was that it is based on who "discharges first" during intercourse:
Sahih al-Bukhari 3329
Narrated Anas:
When `Abdullah bin Salam heard the arrival of the Prophet (ﷺ) at Medina, he came to him and said, "I am going to ask you about three things which nobody knows except a prophet: What is the first portent of the Hour? What will be the first meal taken by the people of Paradise? Why does a child resemble its father, and why does it resemble its maternal uncle?"
Allah's Messenger (ﷺ) said, "Gabriel has just now told me of their answers." Abdullah said, "He (i.e. Gabriel), from amongst all the angels, is the enemy of the Jews." Allah's Messenger (ﷺ) said, "The first portent of the Hour will be a fire that will bring together the people from the east to the west; the first meal of the people of Paradise will be Extra-lobe (caudate lobe) of fish-liver. As for the resemblance of the child to its parents: If a man has sexual intercourse with his wife and gets discharge first, the child will resemble the father, and if the woman gets discharge first, the child will resemble her." On that `Abdullah bin Salam said, "I testify that you are the Messenger of Allah."
This is also narrated in Sahih al-Bukhari 3938, 4480.
A woman does not "discharge" anything during intercourse (or a sexual dream) which has any genetic material in it. A woman's egg is released from her ovaries long before any intercourse could take place in which the egg is fertilized. If what Muhammad says was true, then every child would look like its mother, because the egg is always released before a man's sperm is released. Today, it can be verified that Muhammad said here, and claimed came from Allah, is entirely inaccurate.
In the Quran, a description is given of human development in the womb:
Surah 23:12-14
12 And indeed, We created humankind from an extract of clay
13 then placed each ˹human˺ as a sperm-drop in a secure place,
14 then We developed the drop into a clinging clot ˹of blood˺, then developed the clot into a lump ˹of flesh˺, then developed the lump into bones, then clothed the bones with flesh, then We brought it into being as a new creation. So Blessed is Allah, the Best of Creators.
According to the above, the stages of development are:
The above description cannot rationally be interpreted literally, in the sequence given in the Quran. Instead, it must be reinterpreted to be a poetic description of God forming a child. A literal interpretation is completely wrong, scientifically speaking. However, there are narrations in the Hadith that disallow a metaphorical interpretation of these stages, often giving timeframes for the various steps involved in the development of the child.
For example:
Sahih Muslim 2643a
Abdullah (b. Mas'ud) reported that Allah's Messenger (ﷺ) who is the most truthful (of the human beings) and his being truthful (is a fact) said:
Verily your creation is on this wise. The constituents of one of you are collected for forty days in his mother's womb in the form of blood, after which it becomes a clot of blood in another period of forty days. Then it becomes a lump of flesh, and forty days later Allah sends His angel to it with instructions concerning four things, so the angel writes down his livelihood, his death, his deeds, his fortune and misfortune.
Sahih Muslim 2646
Anas b. Malik reported directly from Allah's Messenger (ﷺ) that he said:
Allah, the Exlated and Glorious, has appointed an angel as the caretaker of the womb, and he would say: My Lord, it is now a drop of semen; my Lord, It is now a clot of blood; my Lord, it has now become a lump of flesh, and when Allah decides to give it a final shape, the angel says: My Lord, would it be male or female or would he be an evil or a good person? What about his livelihood and his age? And it is all written as he is in the womb of his mother.
Above, and elsewhere (Surah 22:5, Sahih al-Bukhari 318, 3208, 6594-95, Sahih Muslim 2643b, 2644, 2645a, 2645c), Muhammad appeared to teach:
Therefore, the Hadith seem to prevent a reinterpretation of Surah 23:12-14. The stages that Muhammad enumerated in the Quran, however, as discussed above, are simply inaccurate.
In all of his teaching on the development of a baby, Muhammad demonstrated ignorance of the fact that a woman had an egg, which was fertilized by a man's seed. Instead, his teaching appeared to be centered on the theory that men and women each discharge liquid semen, which mixes together, with one finally prevailing over the other. He also demonstrated ignorance to the fact that a baby in a mother's womb looks like a little human, with a face, neck, torso, arms, and legs, from about 8 weeks on.
Both the Quran and Hadith contain many scientific inaccuracies pertaining to human reproduction. Some of these can be reinterpreted, in isolation, but taken together, they demonstrate that Muhammad's conception of human reproduction was false, yet, he taught it in scripture, and claimed that it came from God.