The biological clock

Q: I would like to inform Your Eminence that a new product called the "Biological Clock" was advertised in a magazine. The advertisement states: (Part No. 2; Page No. 15)  The biological clock is the indicator of fertility. It helps you control birth and plan to get the desired gender of the child in accordance with the Hadith that reads: If the male fluid prevails upon the female fluid, the baby will be male, and if the female fluid prevails upon the male fluid, the baby will be female. Kindly, find it attached.Your Eminence Mufty, my question is: Do these claims contradict Shari`ah (Islamic law)? Is it permissible to make use of such a clock? Does it really help in selecting the desired gender of the child? I hope that you will answer me. May Allah guide you to what is good and right.

A: It is not permissible to use such a clock for the purpose mentioned above or to believe in it. Actually, all fetus-related affairs such as conception and gender of the fetus belong to the Ghayb which is known only by Allah (Glorified and Exalted be He). Even the angel entrusted with embryos asks his Lord on breathing the soul therein whether it is male or female as stated in the Hadith. Allah (Exalted be He) says: He creates what He wills. He bestows female (offspring) upon whom He wills, and bestows male (offspring) upon whom He wills. Or He bestows both males and females, and He renders barren whom He wills. Verily, He is the All-Knower and is Able to do all things. (Part No. 2; Page No. 16) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family and Companions.