Is the Chinese Gender Chart Accurate?

Chinese Baby Gender Chart or Birth Chart is a set of methods for baby gender prediction summarized from the experience of imperial physicians in Qing Court, which is regarded as a mystery. In Qing Dynasty (1616-1912), the Chart was exclusively used by emperors, princes and concubines in Qing Dynasty and worked well; after the Republic of China (1912-1949), the chart came down to the folk. Some internet forums claim that the prediction by Chinese Gender Chart is quite accurate and it is used by many people to conceive the baby gender they want; in real life, many constantly consult and verify the accuracy of the birth chart.
On the internet, the Chinese Baby Gender Chart is believed to be excavated from the imperial mausoleum a hundred years ago by the archaeologists and has an accuracy rate of 70%; it has calculations, charts, etc. and all the text are annotated with traditional Chinese characters.
Experts' Ideas about Chinese Baby Gender Chart
Experts said the Chinese Baby Gender Chart at best can only be a statistical table, without any scientific nature. In general, boy or girl is just a matter of chance.
"There is no scientific basis for this method. Medically speaking, the prediction has to be more than 90% accurate in statistical probability to be credible, while the prediction by Chinese Baby Gender Chart is only 50% accurate." Experts said the accurate prediction by this method is just by chance and cannot be taken seriously. According to medical experts, the accurate way to predict baby gender is B-mode ultrasound or blood smear made of mother-to-be's capillary blood for dyeing treatment and cell morphology identification with a higher accuracy level. However, medical institutions are prohibited to predict the baby gender with ultrasound diagnosis, chromosome detection and other technical means for pregnancy termination based on gender, unless it is necessary.
A lot of people want to know whether the prediction by Chinese Baby Gender Chart is accurate but it is coincident only. Baby gender is determined by genes which are in turn determined by XY chromosomes in germ cells. There are 23 pairs of chromosomes, i.e. 46 chromosomes in human cells. Comparing the chromosomes of men and women, it turns out that they have 22 pairs (44) of identical chromosomes, which are called ''euchromosomes''. The other pair is very special and it is differently assorted between men and women. For women, the pair is two X chromosomes and for men, it consists of an X chromosome and a Y chromosome. Y chromosome is very small, just about one-third the size of X chromosome and the XY chromosome is called ''sex chromosome''. It is such a small difference in chromosome assortment that leads to different genders.
The newborn has 23 chromosomes from mother and 23 from father, which means each the egg and the sperm provide 22 autosomes and one sex chromosome. Since mother only provides X chromosomes while Y chromosomes are obtained from father, the sex of baby is decided by father rather than mother. Half of the sex chromosomes in a man's sperm are X and the other half Y; the baby gender is decided as soon as the sperm and the egg combine. In theory, the number of boys and girls should each account for 50%, but as a matter of fact, there are about 51.3 boys and 48.7 girls per 100 births and the proportion is roughly the same across countries. There are always slightly more men than women in society. Regarding the phenomenon, scientists have come up with a pretty good explanation: the Y chromosome is smaller and lighter, thus "run" faster and more likely to conjugate with the egg.
Therefore, the conjugation of two X chromosome or one X chromosome and one Y chromosome is beyond human control! 
Experts remind that, the prediction of baby gender by Chinese Gender Chart has no scientific basis; no matter what version it is, do not take it seriously or spend too much time on it but just for fun. The bias for a certain method or food may lead to malnutrition. Couples should take pre-pregnancy checks scientifically to avoid infertility and genetic diseases; take regular checks during pregnancy for the healthy growth of baby. It's the same to have a baby or a girl as long as he/she is healthy and smart.