The chinese calendar and the shettles method (the one that says ttc a few days before ovulation = girl) both would indicate I would be having a girl but just found out I am having my 4th boy this March. I think my husband may just only make y sperm, haha.
I very seriously and carefully used the Shettles method when trying to conceive my 3rd child. I already had 2 boys and really wanted a girl. I charted for months, I took my temperature religiously every morning, I timed intercourse to down to the minute. I got a girl! Eureka! It must have worked. I was so happy.
Then...I got greedy...
I wanted another girl. I very seriously and carefully used the Shettles method again, to make a girl. I did everything the same as when I got the girl. I got...my third boy. LOL. I was still happy though.
An egg is only viable for about 24 hours. Shettles advocates having sex frequently up until 3 days before ovulation and then abstaining to make a girl, or abstaining and then having sex only right at ovulation to make a boy. There are some other details...douching with vinegar or baking soda to make the environment more acidic or base, avoiding/having female orgasm, depending on which gender you're trying for. The real trick is figuring out exactly when ovulation occurs and timing sex accordingly.
OK, this is something I'm also contemplating and this is what I've found/read.
First of all, it's a bad idea to "try one more time for a girl" (not saying that's what you're specifically doing, Delma, just throwing it out there.) Of course, there is a chance you'll get another boy, and you need to be OK with 3 boys or 4 boys or whatever. You (general) shouldn't have more kids than you can afford or are comfortable with just to get a certain sex - you should have another child because you want another child. There are plenty of people with 4 or 5 kids of the same sex so that's very possible.
Secondly, that being said, there's certainly no harm in trying to get one sex or the other if you know you want another baby anyway, and this is what I am going to be trying. You should google this because there's tons of info out there and way too much for me to put in one post, but from what I've read, there are two competing theories on how to conceive a girl.
1) Shettles - have sex a few days before ovulation and then stop until you are certain the egg is gone. Start cutting off sex 4-5 days before O and if that doesn't work after a few months, try 3 days - the closer you get to O, the closer the chances of a boy. This obviously means you need to chart for a few months first to make sure you know how to recognize your signs of O. I have heard that having a girl can take a while and require patience, because the optimal way to get pregnant quickly favours boys.
2) O +12 method - claims Shettles is bunk and you should have sex 12 hours AFTER ovulation before the egg is gone - this is obviously tricky because a) you have to know exactly when O is or you can miss your chance to get pregnant at all or b) you and your partner have to be both available for sex at a very specific and limited and possibly inconvenient time or c) if your timing is a little off, you could be having sex right close to O which is Shettles boy timing. You have to be using ovulation tests and temping all the time. I'm not personally a fan of this method, but some swear by it. Some do both - a Shettles cut-off and then try to hit O + 12 as well.
From what I've read, neither of these methods is an iron-proof guarantee, and some believe you get what you get no matter what. Also, I have seen studies that even if you have several kids of one sex, it doesn't significantly reduce your chances to have the other sex, but the more boys you have, your chances of a girl do go down slightly.
There are also beliefs that your diet, lifestyle etc. have an impact - both woman and the man - as the acidity of the vaginal environment or the conditions by which the man makes sperm are affected by this. Some of the things I've heard that work are:
for the man - hot baths before sex, tight underwear (kills off the less resilient male sperm - but also make the man produce less sperm and be less fertile in general, so if there are any fertility issues, this may not be for you)
for the woman - use Benadryl to dry up cervical fluid (helps keep male sperm alive longer, but again, also reduces chances of pregnancy in general)
for both - there are "girl diets" you can go on - to my memory, there are supplements people take and certain things to avoid (dairy, meat etc.) You can google for this - the girl diet is very restrictive as the goal is to reduce calories - it is believed that more girls are conceived in times of hunger. It is also believed that women at a lower body weight are more likely to conceive girls, so some weight loss (if applicable) may help. Anecdotally, every really large woman I know has had primarily boys and most of the really thin ones have had girls, for the little that's worth. I've also heard that girls are more likely to be conceived while nursing.
From my own personal experience, I had Shettles conditions for boys with both my boys - not sure whether that was a coincidence or not. I was trying to get pregnant as quickly as possible so we had sex right up to O, and I had a lot of cervical fluid and was encouraging this with lots of water, etc. I also had most (but not all) of the boy diet and some of the other factors. So I'd probably give Shettles a shot first when my time comes.
Get used to me. Black, confident, cocky; my name, not yours; my religion, not yours; my goals, my own; get used to me. -Muhammad Ali
Honestly I want one more baby anyway boy or girl, but obviously I'd like a girl or I wouldn't have asked about this. But I love my boys so having another one wouldn't be a big deal. I don't want to try for a while but would like one more child before I'm 35 so I do want to at least give it a try to have a girl.