How to ensure the sex of your baby

Dear Doctor,
I met this lady two years ago and we have one girl. I would like to have three to four kids, possibly three boys and one girl. How do I get boys now? Regards, CF
Dear CF,
I am sure you have your own reasons for wishing that your subsequent babies are all boys. It doesn’t seem like you are looking for a family balance, as you clearly want more boys.
But sex selection purely for social reasons has ethical and demographic dilemmas, and is medically illegal in many jurisdictions. However, advanced medical technology and increasing demand for sex selection have both created the need for more debate on the matter.
There is a push for relaxation of the rules on a selective basis, and more couples may have a chance to pre-select the desired sexes of their future children.
Sex determination is dictated by chromosomes (structures that contain genes) carried by sperms. Females have the XX chromosome complement, while males are XY. If an X bearing sperm fertilizes an egg, a baby girl is conceived. Conversely a baby boy will be conceived if a Y bearing sperm fertilizes an egg. Thus having a boy or a girl occurs purely by chance.
But can you influence the chances of having either a boy or a girl? You will find common advice based on physical characteristics of X or Y bearing sperms. This includes the timing of sexual intercourse in relation to expected time of ovulation, certain sexual positions, and even changing your diet. Such advice is very imprecise and has not been scientifically proven to influence eventual sex of the baby. You might as well toss a coin!
More scientifically sound methods of sex selection are available, but must be combined with assisted conception techniques. X and Y bearing sperms can be separated with laser guided techniques. The desired sperms can subsequently be inseminated into the womb, with over 90 percent chance of success.
In-vitro fertilization (IVF) can be used to preselect fertilized eggs (embryos) of the desired sex. This virtually guarantees conception with the desired sex, but is only licensed in cases where a medical reason for sex selection exists. Accessing such techniques for social sex selection is limited by cost, and the law.
Guaranteeing that your next baby will be a boy through natural conception is at best a gamble. Be ready to raise whatever sex you get, statistical chances are that you will father a boy as the number of the children your bear increases.