When is the gender determined?

When exactly is it that the sex of the baby is created? How long after ovulation or sex does it happen?

During fertilization

And fertilization occurs when u are ovulating and the sperm meets the egg? Yes?

You ovulate, the egg travels until it meets the sperm and once the sperm penetrates the egg, fertilization has happened and gender is then determined.

I've probably asked this before but does anyone think that what u ate on the day of fertilisation determines the gender at all?

I don't think it does, honestly. It doesn't really make sense from an evolutionary standpoint that what you ate the day sperm meets egg would determine gender rather than the condition of your body for several months prior to conceiving. Additionally, I have seen tons of opposites from women who did the diet only the week of conception. If what we ate the week of conception matters so much why wouldn't everyone who was perfect on the diet the few days around O always get girls? It seems the longer on the diet, the better the results which to me points to the biochemical markers on the egg (or whatever it is that makes swaying work!) is something that develops over weeks and months rather than days.

No, what you ate that day will not determine gender.

I hope so cos I had a big fat cheat on the day we DTD.and only 4dpo and finding it hard meat wise as I've ate quite a bit if meat.I've stayed within limits maybe a bit over as I stopped tracking for a while.I lost about around half a stone.been on the diet loosely from around June then got stricter and near enough vegetarian as time went on.just hope if I see a bfp this month I've done enough to get my girl.xx

Women have XX chromosomes. Men have XY chromosomes. Sex cells (eggs in women and sperm in men) have half the number of chromosomes of a normal human cell so that when they come together the resulting baby has the correct number again.
Essentially all eggs are 'female' (x chromosome) whereas sperm is 50% 'female' (x chromosome) and 50% 'male' (Y chromosome).
Gender is therefore down to the sperm that fertilises the egg; if an 'x' gets there first you get a girl (xx chromosomes) and if a 'y' gets there first the resulting embryo will be male (XY chromosomes).
Swaying tries to stack the odds in your favour by changing your internal environment, decreasing your condition etc but (even atomic will agree) a lot of the mechanics of this are still unknown. The sex of the child is determined by the sperm that fertilises the egg.
Hope that helps and good luck :) xx

it happens when sperm hit the egg. The reason we do diet longer than that is so the XX or XY have the best environment for their development after fertilization. XX may prefer lower glucose environment, XY higher. (we're not sure how much this really matters and it's very likely that both can develop perfectly fine in a wide range of environments.) But more importantly, it's so you aren't off the diet for two weeks in case of BFN.