sex ratio linked to mothers age when she began menstrating.

I do not know if anyone has seen this study so i figured i would share.
http://humrep.oxfordjournals.org/con...er107.abstract

interesting article, my first period age is 11 and seems early and have 2 dd.. Early menarche is genetic for me and grandma has 6 DDs no DS my mom has 2 DDs and 1 DS. My aunts mixed A1 has 3 DS and 1 DD, A2 has 1 DS, A3 has 1 DD, A4 has 1DS, A5 has 1 DS and 1 DD.. Considering all had early menarche i can assume i have chance for a boy :)

Still confused as to what I should have based on that... I started on my 12th birthday and have had 3 male births. My stepmom was 16 and had B, G, G. My biomom was 14 and had G, B, G, G, B. My dads mom was 18 and had G, B, B, B, B. My moms mom was about 17 and had G, G, G, B, B, B, G, B, G (all a year apart but 3B's were stillborn).

So with this research at what age do I get a girl?

I think 12-14 were boys, and 9-11 girls and 15+girls again. I was almost 15, so right on the cusp of boy girl. Hopefully one of each!

See I was in the 12-14 range and have 3 girls, of course I unknowingly had a perfect girl sway lol

I was just 11 and have two boys so far.
My aunt was 9 and had two boys
My Mum was 10 and had two girls.

Hmmmm, I'll add mine:

I was 13 and conceived G, B, B.
My mom was a month shy of 13 and had B, G
My maternal aunt was 16 and had B, B.

So if mine happened on my 12th b-day maybe I have a chance :)

this is interesting. The abstract was a little confusing to me, too. Maybe somebody who knows that lingo better can write it out in plain English?

I can add mine and my mom's info:

My mom started at 11 and had B (stillborn), G, B and many, many miscarriages where gender was unknown
I started at 14 and had G, B, B, B, and G on the way now.

I was 11 and have so far, all girls.