Friday, May 8, 2009

Is it a boy or a girl? The odds of each gender


Source: Knockedupcelebs.com

Sometime in February before I left NYC I remember walking along the Hudson with Mamas A and V (all of us boy mamas). We somehow got on the subject of what sex we had hoped our first baby would be and what our husbands had hoped for. I can't remember the specifics but something Mama A mentioned that she'd read something that said that the odds of your second child being the same sex as the first child are actually higher - so you're more likely to have a boy for number two if your number one is a boy and same for girls.

If you look around at our group alone Mama LS (welcome our newest blogger!) has recently had her second boy, another friend V is having her second boy any day now and our own Mama J is expecting her second boy in September. All my friends here in London are having two boys! I'm not making this up. All of them! Strange...

We've decided not to find out the sex of our baby. Mr M wants another boy because he "won't know what to do with a girl". He thinks this baby is a girl. I'm fine either way. A little boy would be a nice playmate for Master R as there's only 18mths between them. But a little girl is just beautiful. All the wonderful little dresses I could knit/crochet/sew for her! The ribbons in her hair and the pretty mummy and me outfits - ok, that's a bit crazy... Now I'm thinking maybe we should have found out? The wait is killing me...

So after pondering the odds I stumbled upon this fantastic research by InGender: The straight truth about gender selection. The numbers are all a little off because of the fact that of all births in the US 51% are boys anyway. So this needs to be taken into account when you look at subsequent births.

You'll need to look at the site to get the full gist of the stats. But interestingly the odds of having a girl seem decrease after having each boy, but only very slightly. Even after 3 boys, you are only 6.4% more likely to have a 4th boy than a girl. The odds of having a boy seem to increase after having girls, except after 2 girls, when a 3rd girl is more likely.

"The bottom line: Although we often hear the "statistic" that you are 30% or even 70% more likely to keep having the same gender, this is just an old wives tale. It is NOT a fact. The truth is, your odds stay pretty close to 50% for each child and only vary slightly. If you have had 2 or 3 boys, you are only about 2% to 6% more likely to have another boy. If you have had girls, you are slightly more likely to have a boy next."

Hmm so there's a 2-6% chance I'm having another boy. Mama J do you still think I'm having a boy?

2 comments:

  1. I'm going to venture out there and say I think you are going to have a girl. I'd also like to know what Mama J thinks...

    ReplyDelete
  2. I still think it's a boy- but hope it's a girl for you Mama N. Mr. M may go into debt w/your knitting though if it's a girl!!!

    ReplyDelete