Muhammad on Human Reproduction: Does Science Show That Islam Is True?

By David Wood

Muslim reverence for Muhammad’s supposed scientific precision can hardly be exaggerated. Indeed, according to many Muslims, Muhammad even led the scientific revolution:

It was [Muhammad] who turned the course of human thought away from superstition, the unnatural and the unexplainable, towards a logical approach illustrating a love for truth and a balanced worldly life. … It was he who, in the place of baseless speculation, led man to use logic and reasoning on the basis of observation, experimentation and research. He was the one who clearly defined the limits and functions of sense perception, reason and intuition.i

Exaggerations aside, the scientific accuracy of Muhammad’s statements is notorious for being singularly unimpressive to anyone who isn’t already a committed Muslim. The tactic employed by Muslim apologists is (1) to read a simple verse from the Qur’an, (2) to twist and stretch the interpretation until it conforms to modern science, and (3) to proclaim that there is absolutely no way an illiterate, seventh-century leader could have revealed all these scientific insights without the help of God. After hearing such arguments, Muslims typically stand in awe. Others stand there wondering, “Where did the verse say that?”

The purpose of this article is not to respond to the many alleged instances of scientific accuracy in the Qur’an. Instead, I will show that the Muslim approach is unpromising, for the Argument from Scientific Accuracy cuts both ways. That is, one cannot reasonably point to Muhammad’s scientific insights while turning a blind eye to his numerous scientific inaccuracies. As it turns out, this is exactly what Muslims do. A brief discussion of Muhammad’s views on human reproduction should prove this point.


According to the Qur’an, semen is formed somewhere between the ribs and the backbone. We read in Surah 86:5-7:

Now let man but think from what he is created! He is created from a drop emitted—Proceedings from between the backbone and the ribs.ii

Muslim commentator Yusuf Ali tries to rescue this passage by interpreting it metaphorically:

A man’s seed is the quintessence of his body. It is therefore said metaphorically to proceed from his loins, i.e., from his back between the hipbones and his ribs. His backbone is the source and symbol of his strength and personality. In his spinal cord and in the brain is the directive energy of the central nervous system, and this directs all action, organic and psychic. The spinal cord is continuous with the Medulla Oblongata in the brain.iii

I would normally have no objection to interpreting statements in the Qur’an metaphorically. However, such reinterpretation becomes difficult when Muslims are employing an argument based on scientific accuracy, and when they are forced to radically reinterpret some of the clearest scientifically testable claims in the Qur’an.


Muhammad adds in the Hadith (collections of his sayings and deeds) that women have a discharge similar to the semen in men:

Man’s discharge (i.e. sperm) is thick and white and the discharge of woman is thin and yellow.iv

Muslims often try to interpret this passage as referring to the genetic material in the ovum. However, such an interpretation is impossible, since Muhammad claimed that it was quite visible (and the genetic material inside the ovum isn’t):

Umm Salama said: “O Allah’s Apostle! Allah does not refrain from saying the truth! Is it obligatory for a woman to take a bath after she gets nocturnal discharge?” He said: “Yes, if she notices the water (i.e. discharge).” Umm Salama smiled and said: “Does a woman get discharge?” Allah’s Apostle (the blessing and peace of Allah be upon him) said: “Then why does a child resemble (its mother)?”v 


According to Muhammad, reproduction begins when the thick, white discharge of a man mixes together with the thin, yellow discharge of a woman. Interestingly, Muhammad claims to have received knowledge of this from the angel Gabriel, who told him that the child’s appearance is determined by which parent has the first discharge:

Allah’s Apostle said: “Gabriel has just now told me of their answers” [to the questions he had been asked]. . . . 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 Apostle of Allah.”vi

Anyone who has taken high school biology knows that this is completely wrong.


In addition to explaining how a child’s appearance is determined, Muhammad tells us how the gender of a child is determined.

[Muhammad] said: The reproductive substance of man is white and that of woman yellow, and when they have sexual intercourse and the male’s substance prevails upon the female’s substance, it is the male child that is created by Allah’s Decree, and when the substance of the female prevails upon the substance contributed by the male, a female child is formed by the Decree of Allah.vii 

Notice that this passage states that a child will be male if the substance contributed by the father prevails, but female if the substance contributed by the mother prevails. This is false; the sex of a child, whether male or female, is determined by the sperm contributed by the man.

Returning to Muhammad’s stance on reproduction, once the male sperm mixes with the female sperm, development takes place rather slowly. The developing human spends several weeks as a collection of sperm, then spends another several weeks as a clot of blood. This view is supported by the Qur’an and the Hadith:

(Consider) that We created you Out of dust, then out of Sperm, then out of a leech-like Clot, then out of a morsel Of flesh, partly formed And partly unformed, in order That we may manifest (Our Power) to you. (Qur’an 22:5)

It is He Who has Created you from dust, Then from a sperm-drop, Then from a leech-like clot; Then does He get you Out (into the light) As a child. (Qur’an 40:67)

Man We did create from a quintessence (of clay); then We placed him as (a drop of) sperm in a place of rest, firmly fixed; then We made the sperm into a clot of congealed blood; then of that clot We made a (foetus) lump; then We made out of that lump bones and clothed the bones with flesh; then We developed out of it another creature. So blessed be Allah, the Best to create! (Qur’an 23:12-14)

[Muhammad said]: Allah, the Exalted 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?viii

Allah’s Apostle (the blessing and peace of Allah be upon him), the true and truly inspired said: “(The matter of the Creation of) a human being is put together in the womb of the mother in forty days, and then he becomes a clot of thick blood for a similar period.ix

[Muhammad said]: When forty nights pass after the semen gets into the womb, Allah sends the angel and gives him the shape. Then he creates his sense of hearing, sense of sight, his skin, his flesh, his bones, and then says: My Lord, would he be male or female? And your Lord decides as He desires and the angel then puts down that also.x

These passages yield numerous insights. Muhammad suggests that the earliest stage of human development is the sperm stage, which lasts for a period of forty days. The next stage is the blood-clot stage, which also lasts around forty days. The sex of the child is determined after the first stage and after the developing person has been given hearing, sight, etc. Bones are formed before flesh. All of these statements are, of course, false. Sperm can survive up to a week once they have been released, but they certainly don’t last for forty days. There is no such thing as a blood-clot stage, let alone one that represents a significant portion of early embryonic development. A child’s sex is determined genetically as soon as the sperm enters the egg. Bones don’t form before flesh. Cartilage forms early on along with the flesh. But by the time the cartilage ossifies into bone, muscles have already formed.


Putting all of this together, we have Muhammad’s view of human reproduction. Semen forms between the backbone and ribs (false). Then it joins with the female semen (false), and whichever one is discharged first determines which parent the child will resemble (false). The child spends forty days as a drop of sperm (false). Then the child spends another forty days as a clot of blood (false). Next, the child becomes a lump (false). Then the child becomes bones (false). Then the bones are wrapped with flesh (false). After the final shape is determined, God finally decides whether the child will be male or female (false).

Apart from the fact that semen has something to do with human reproduction, Muhammad was wrong in every possible way. The Muslims solution to all of these errors is, again, to radically reinterpret these passages. But here we have rather conclusive proof that the Argument from Scientific Accuracy is circular. Muslims assume, from the beginning, that Muhammad was a prophet and that he therefore couldn’t have spoken falsely. They then use this assumption to reinterpret all of Muhammad’s scientifically inaccurate claims. Once they have reinterpreted all of Muhammad’s claims to bring them in line with modern science, they proclaim, “Isn’t it amazing that Muhammad got all of this right? He must be a prophet!” But this is what the argument required them to assume from the start.

If there were some compelling reason for us to regard Muhammad as a prophet, perhaps we would be justified in interpreting his statements as completely accurate, as Muslims do. For example, if Muhammad had risen from the dead (as Jesus did), we would have God’s stamp of approval on his message. But we have nothing of the sort in Islam. In the absence of strong evidence, we must take Muhammad’s statements for what they appear to be: the sometimes accurate, mostly erroneous speculations of an intelligent but superstitious man.


iAbul, A’la Mawdudi, Towards Understanding Islam (New York: Islamic Circle of North America, 1986), p. 62.

iiAll Qur’an quotations are from the Yusuf Ali Translation.

iiiYusuf Ali, note on Qur’an 86:7.

ivSahih Muslim 608.

vSahih Muslim 3328.

viSahih Muslim 3329.

viiSahih Muslim 614.

viiiSahih Muslim 6397.

ixSahih al-Bukhari 3208.

xSahih Muslim 6393.


Published March 30, 2016