Miracles in the Quran : Embryology (taken from www.islam-guide.com)

"We created man from an extract of clay. Then We made him as a drop in a place of settlement, firmly fixed. Then We made the drop into an alaqah (leech, suspended thing, and blood clot), then We made the alaqah into a mudghah (chewed substance)... " (Quran, 23:12-14)

alaqah has three meanings: (1) leech, (2) suspended thing, (3) blood clot

Figure 1: Drawings illustrating the similarities in appearance between a leech and a human embryo at the alaqah stage. (Leech drawing from Human Development as Described in the Quran and Sunnah, Moore and others, p. 37, modified from Integrated Principles of Zoology, Hickman and others. Embryo drawing from The Developing Human, Moore and Persaud, 5th ed., p. 73.)

Figure 2: We can see in this diagram the suspension of an embryo during the alaqah stage in the womb (uterus) of the mother. (The Developing Human, Moore and Persaud, 5th ed., p. 66.) (Click on the image to enlarge it.)
Figure 3: In this photomicrograph, we can see the suspension of an embryo (marked B) during the alaqah stage (about 15 days old) in the womb of the mother. The actual size of the embryo is about 0.6 mm. (The Developing Human, Moore, 3rd ed., p. 66, from Histology, Leeson and Leeson.)

Figure 4: Diagram of the primitive cardiovascular system in an embryo during the alaqah stage. The external appearance of the embryo and its sacs is similar to that of a blood clot, due to the presence of relatively large amounts of blood present in the embryo. (The Developing Human, Moore, 5th ed., p. 65.) (Click on the image to enlarge it.)

The next stage mentioned in the verse is the mudghah stage. The Arabic word mudghah means “chewed substance.” If one were to take a piece of gum and chew it in his or her mouth and then compare it with an embryo at the mudghah stage, we would conclude that the embryo at the mudghah stage acquires the appearance of a chewed substance. This is because of the somites at the back of the embryo that “somewhat resemble teethmarks in a chewed substance.”(see figures 5 and 6).

Figure 5: Photograph of an embryo at the mudghah stage (28 days old). The embryo at this stage acquires the appearance of a chewed substance, because the somites at the back of the embryo somewhat resemble teeth marks in a chewed substance. The actual size of the embryo is 4 mm. (The Developing Human, Moore and Persaud, 5th ed., p. 82, from Professor Hideo Nishimura, Kyoto University, Kyoto, Japan.)