Take, for example, the Quran's highly controversial statement that human beings are formed from a clot of blood. "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" (23:14).
This is hardly a scientific description of embryonic development. It ignores to mention the female egg (the second and equally important half) and the process of fertilization when egg and sperm unite to form one new cell.
It mentions the obvious [the sperm], the visible, that which all mankind knew for a long time that it is necessary to "make" a baby. The Qur'an does NOT mention the invisible, that which we know only through modern medicine. Had God really wanted to reveal something nobody could know at that time, in order to prove the divine origin of his revelation, he would have talked e.g. about the "equal contribution of the female through the ovum to form the new person and how the two come together and form one being".
Contradictions in the Qur'an
Answering Islam Home Page