The Qur’an describes the next stage of the developing human embryo with the word `alaqah. This word carries various meanings including: to hang, to be suspended, to be dangled, to stick, to cling, to cleave and to adhere. It can also mean to catch, to get caught, to be affixed or subjoined.48

Other connotations of the word `alaqah include a leech-like substance, having the resemblance of a worm; or being of a ‘creeping’ disposition inclined to the sucking of blood. Finally, its meaning includes clay that clings to the hand and thick, clotted blood - because of its clinging together. 49

As defined by modern embryology, the myriad of meanings for the word `alaqah correspond to various stages of the embryo’s development. Comparisons can be drawn between qu’ranic and scientific depictions of the embryo's appearance and its relationship with the womb. According to modern embryology, from day 15 the embryo is hanging or suspended via the ‘connecting stalk’ [see Figure 1] and it obtains nutrients through contact with the maternal blood vessels. This description bears a striking resemblance to the picture painted by the word `alaqah – a ‘hanging’ or ‘suspended’ substance, obtaining nutrients from its host’s blood.

Following this, during the 4th week, two processes occur: the formation of the brain and the spinal cord, known as neurulation; and the initial stages of the folding of the embryo. It is upon the culmination of these two processes that the embryo resembles a leech-like form suggested by the word `alaqah – a creeping, leech or worm-like substance [see Figure 2, 3 and 4].

Embryologists Barry Mitchell and Ram Sharma explain the ‘hanging’ or ‘suspended’ aspects of the `alaqah stage. They describe the embryo as being, “connected to the cytotrophoblast by a connecting stalk of extra-embryonic mesoderm (primitive connective tissue). The stalk is the forerunner of the umbilical cord.” 50 Figure 1 shows the embryo connected to the cytotrophoblast via a connecting stalk, as if it were hanging or suspended.

With regard to the way the embryo obtains its nutrients through contact with the maternal blood vessels, Barry Mitchell and Ram Sharma write: Due to the rapid growth of the embryo during the second week, there is a need for a more efficient means of nutritional and gaseous exchange. This is achieved when the embryonic blood vessels of the chorion come into contact with the maternal blood vessels of the decidua.51.

... [by the third week]... The exchange of nutrients, respiratory gases and waste products between the maternal and fetal blood takes place across the placental membrane within intervillous spaces. Maternal blood enters these spaces from the spiral arteries, branches of the uterine artery, bringing nutrients and oxygen for the embryo and fetus.52

This reinforces the validity of the meanings of `alaqah, and its evoking images of an entity obtaining its nutrients via blood.

The `alaqah stage suggests the process of neurulation and the initial stages of the folding of the embryo. Neurulation comprises of the formation of the brain and the spinal cord from days 19 to 25 (approx.); and the folding of the embryo involves the head and the tail being brought closer together. The combination of these two physiological changes causes the embryo to resemble a leech-like substance.

At the end of neurulation the cranial and caudal ends of the neural tube close. The embryo, at this point, becomes leech-like in appearance 53 [see Figure 2].

Barry Micthell and Ram Sharma explain the process of neurulation.

At about 19 days, at the cranial end of the primitive streak, the underlying mesoderm and notochord induce the ectoderm to form the neural plate, which rounds up to form the neural folds. The neural plate enlarges initially at the cranial end. At 20 days, the neural plate in the mid-region of the embryo remains narrowed, but it expands at the caudal end. The plate deepens to form the neural groove from which the neural tube forms. The cranial and caudal ends of the tube are open and are known as the anterior and posterior neuropores; these eventually close. 54

The folding of the embryo is also responsible for forming a leech-like shape [see Figure 3], or as embryologists have described; a cylindric or tube-like structure. Embryologists Keith Moore and T. V. N. Persaud suggest that:

A significant event in the establishment of body form is the folding of the flat trilaminar embryonic disc into a somewhat cylindric embryo. Folding results from the rapid growth of the embryo, particularly the brain and the spinal cord. 55

The tube-like or leech-like structure [see Figure 4], as explained by Barry Mitchell and Ram Sharma, is due to:

longitudinal folding, which occurs between days 21 and 24, result[ing] in … the embryo [bending] so that the head and tail are brought closer together...[to] form a tube-like structure. 56

The `alaqah stage:

The embryo is connected to the cytotrophoblast via a connecting stalk, as if it were hanging or suspended.

The formation of the brain and the spinal cord, known as neurulation; and during the initial stages of the folding of the embryo. It is upon the culmination of these processes that the embryo appears leech-like.

The embryo obtains its nutrients via contact with the maternal blood vessels. This mirrors the action of a leech-like substance obtaining its nutrients via blood.

Critics declare that the use of the word `alaqah is a description of Galen’s second stage of the human embryo. Their translation of the word `alaqah to ‘blood clot’ creates an impression of Galen's description of this stage:

But when it [the clot] has been filled with blood, and heart, brain and liver are still unarticulated and unshaped yet have by now certain solidarity and considerable size, this is the second period; the substance of the foetus has the form of flesh and no longer the form of semen. 57

There are a number of weaknesses with the implications of these critics:

1. Firstly, the Qur’an does not make a mention of the “heart, brain and liver...

[being] unarticulated and unshaped yet [with] a certain solidarity and [of a] considerable size”.

2. Secondly, the word `alaqah does not mean blood; rather, its primary meanings are ‘a clinging form’ and ‘a leech-like substance’. Some Arab linguists would attribute the meaning of a ‘blood clot’ to the word `alaqah, not because of it being filled with blood, but instead due to it ‘clinging’ by nature. This interpretation matches the primary meaning of the word.

3. Thirdly, Galen insists “the foetus has the form of flesh” during the second stage, whereas the Qur’an affirms the mudghah (a chewed piece of meat or lump of flesh) stage comes after the `alaqah stage.

4. Fourthly, in his book On the Natural Faculties, Galen writes: so it is with the semen: its faculties it possessed from the beginning.58 Galen’s incorrect implication of the semen’s sole responsibility for the genetic material is incompatible, and in direct opposition, to the Qur’an and Prophetic traditions. As previously explored (see Aristotle, Galen & Nutfah) the Islamic source texts considers the nutfah as a mingled drop or fluid from both the male and the female, and confirm both the male and female as responsible for the genetics of the child.59 Therefore, if the Prophet ﷺ copied Galen’s views on human development, how is it that he rejected the incorrect science and only used what was correct, even though there was no way in 7th century Arabia of knowing which views were accurate?

Contemporary commentators argue the embryo only looks leech-like when the yolk sac is removed, and that the `alaqah's description is therefore a misrepresentation of the embryo’s appearance at this stage. However, embryologists explain that the yolk sac is separated from the embryo by an extra-embryonic feature, called the extra-embryonic coelom. This fact disproves claims of misrepresentation as the yolk sac is not part of the structure of the embryo.60