“It seems likely that when there are large and predictable costs associated with producing and/or rearing either sons or daughters in a given environment, females should bias offspring sex ratios to produce the sex that will perform best in the given environment,” co-author Sarah Pryke told Discovery News.

“Altering offspring sex ratios in response to the quality of the local environment is likely to be highly advantageous to any species, as it should allow mothers to best match the phenotype of their offspring to the prevailing condition, and thus maximize their own fitness,” added Pryke, a researcher in Australian National University’s Research School of Biology.

Originally posted by Neopan100
I'm by no means an expert..but, supposedly there are methods to up a womans chances for girls/boys/twins. I used the chinese calendar for my two girls and now working on third girl. Everyone I know that uses this method along with shettles methods seem to get the sex they want. If you haven't heard of them you can look up ovulation calculators that will determine when you should have sex for girl or boy. To produce a girl start with the chinese calender for the best month to try for the desired sex..then for say a girl you are supposed to have sex a week prior to ovulation up until 2 days before ovulation. A woman wanting boy should start having sex on the day of ovulation and for two days after ovulation.

To help produce natural multiples a woman is suppose to up her folic acid over 800 mcg/day for 2 months or more before TTC. Also consuming yams, sweet potatoes and carrots, along with upping dairy intake and gaining weight over 20lbs also ups a woman's chances for multiples.

edit on 1-8-2012 by Neopan100 because: (no reason given)

Wow, any special tips on getting pregnant period?

It seems like I also heard about more boys being born during war times. I'll try to find the article as well.

I think this is pretty cool if true. Though, I have known many women who want a girl, think girl the whole pregnancy, swear they are having a girl, and they end up having a boy. And vice versa. So, I guess who knows?

Edit:

"The family tree study showed that whether you're likely to have a boy or a girl is inherited,” says Gellatly. “We now know that men are more likely to have sons if they have more brothers but are more likely to have daughters if they have more sisters.” Women, however, did not have the same tendency.

Originally posted by Neopan100
reply to post by tport17

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Start tracking your ovulation very closely. If you don't know (cant feel) yourself ovulating, I recommend buying those kits. Track for two or three months and then try having sex everyday or at least every other day for the entire time after your period. Some women ovulate the day after their period so if you don't know then just do it often.

Another tip -- Lay still and on your back for at least 15 -20 mins after intercourse. Laying still doesn't allow the sperm to leak out. God that was totally TMI

Originally posted by Neopan100
reply to post by luciddream

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They don't have to be extreme. Changing the pH in a woman's vagina determines which of those sperm get through easier. At different times of month a woman's pH can either be very alkaline or very acidic. Also if a woman has an orgasm during sex will change the pH allowing more of the slower male sperm through..