Brief Answer:
There is absolutely nothing you can do to increase Y chromosomes in sperms.

Detailed Answer:
Hello Mr XXXXXXX XXXXXXX

Thank you for your query.

I am sorry to disappoint you but this question is suggestive of how very wrongly informed you are about the reproductive physiology of human beings.

There is absolutely no way to increase the chances of occurrence of Y chromosome in the spermatozoa.

Each spermatogonium undergoes meiosis (a specific way the cell divides) and these contain diploid number of chromosomes (2 of each chromosomes).

In the first phase these chromosomes undergo duplication and then the cell divides into two equal halves, so at the end of this phase each cell will contain a pair of each of the 23 chromosomes.

In the next step however, the chromosomes do not undergo duplication, instead the two new cells that form will carry one chromosome set only, that is, 23 chromosomes only, not a pair of 23 chromosomes.

So, at the end, each of the 4 newly divided cells will contain 22 autosomes and one sex chromosome. 2 of these cells will contain one Y chromosome and 2 will contain X chromosome.

No matter what you do, you can never change this.

The fact that you have had 4 daughters only till now is just pure chance and nothing else.

Now that you have 4 daughters, you might consider to stop having children.

Both male and female children equally good.

In this 21st century and being educated I hope you are not one of those persons who values male children more than female children. ( I would refrain from passing judgement on other people, but this is disgusting way to think in my honest opinion).

I can understand that there may be societal and family circumstanced which may make you wish you had some way out of this, but there is none, and you should stop valuing the idiotic societal norms, and if someone says that you must have male children and should try to do something about it, you can now -armed- with this knowledge can tell them to their face that there is nothing to be done in this case.

I hope you find this information useful, please feel free to write back to me if you have any additional questions.

Best regards

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