When does the gender of the baby get decided?

After some testing I do believe it's fairly set at conception - but able to be influenced!

I had a save half a day before my sim gave birth. During the pregnancy I carefully avoided carrots, strawberries, radio, and tv. I restarted the game many times to test the gender.

7 times in a row she gave birth to a girl. On the other 3 attempts, I had the sim eat carrots and listen to alternative music. Twice, she had a boy, and once she had a girl.

That many only be 10 times but I think it's fairly reliable results!

The baby's characteristics, gender included, are determined at birth. I stumbled upon this in a play through where the father was bitten and turned into a vampire after conception, but before birth. The child was born a vampire -- something that should have not occurred if this was not the case. And so, at the moment of birth the game randomizes characteristics from the two parents at that time, not at conception. It will evidently also take into consideration the foods eaten and music listened to in determining gender probability at that time as well. This makes sense, as it seems to utilize the three day period between conception and birth as a running counter to skew statistical probability and then does its calculating at the end.

EDIT -- Nuts. This thread is from last year. I already replied to it. Well, there it is.

I read things like 'if your sim eats strawberries during pregnancy they're more likely to have a girl' and 'if they watch the children's TV channel they're more likely to have twins' etc, I don't know whether or not these are definitely true but I have always assumed the gender was decided at birth depending on things like this? Don't quote me on this though :joy:

"rosemow;c-15909653" wrote:
Hello
The feature to be able to influence the gender of your baby was brought into the game in May 2015 through a game patch

Sims can now influence the gender of their offspring!
Strawberries and Pop music (one, the other, or both) seem to lead to more baby girls.
Carrots and Alternative music to more baby boys.

Awesome, thank you!!
@rosemow Is there anything that influences twins except the sim and lot traits?

Good to know, thanks!

For the record, it doesn't matter what you eat in real life. The sex is determined at conception according to the sperm. But now I'm curious because with mcc the pregnancy seems to be set in stone. I often check to see what my sim is having to plan out names or rooms and it's never changed thus far for me.

It's not set in stone with MCCC, first of all you can change it using that. Also if you influence it with the carrots or strawberries it does change. I've done it many times. Three of either seems to do the trick. I never even use the music and have always been successful.

I also use MCCC and can tell right away what gender(s) the babies will have. So far it has not changed for me if I leave it alone, but in cases where my family only has girls/boys for generations, I've made the mom eat carrots or strawberries to change it. That's always worked for me.

I just played and my sim is in her 2nd trimester. Savef. Then had her doctor husband determine gender and got girl twice. Third time had mom eat 5 carrots and listen to alternative music before determining gender. Got boy. Natural gameplay no interference

It's determined at conception. There was a bug awhile ago that sometimes made the gender shift I could never figure out if it was mod failure or just a bug, but it's been gone for awhile. You can of course change it through actions, but I have never tried through the in-game actions. My babies always come out like MCCC's scanner says they will. It's not set in stone at conception, but the gender is chosen then. It's just "set" after birth so long as you didn't influence it.