minervasmom

Scientific studies + timing

2010-03-20T01:16:00Z

One of the "truisms" in swaying is that timing is of minimal importance. Shettles' theories have largely been disproven, timing is listed as the least important of the seven swaying factors, and many assume that as long as the environment is right, timing really doesn't matter. Part of the reason for this dismissal of timing seems to come from the apparent lack of scientific studies supporting it.

One such scientific study that finds no evidence for timing is "Timing of Sexual Intercourse in Relation to Ovulation - Effects on the Probability of Conception, Survival of the Pregnancy, and Sex of the Baby." The study analyzes the last day intercourse occurred on and "[finds] no association between the sex of the baby and the timing of intercourse in relation to ovulation."

http://nejm.highwire.org/cgi/content/full/333/23/1517

The problem with this study is a problem I suspect a lot of timing studies have: it is looking at the wrong timing patterns. Most BD patterns do not sway, or if they sway, it is probably just by a small amount. There are only a handful of BD patterns I have found that may significantly influence gender (these are the patterns that I have at least 20 charts for and that have a greater than 55% effectiveness rate):
- 1 time BD the day before ovulation (23 charts): sways boy 65.2%
- 2 day cut-off (44 charts): sways girl 56.8%
- 3 day cut-off (22 charts): sways girl 68.2%
- frequent BD (at least 4 times) with a 1 day cut-off (26 charts): sways girl 69.2%
- frequent BD (at least 4 times) with a 1 day cut-off AND BD the day after ovulation (45 charts): sways girl 57.8%
* And, of course, I think O+12 also sways, but I can't evaluate it in my study.

If a study isn't looking for one of the handful of timing patterns that may sway, it is unlikely to find any evidence that timing works. For instance, the study above looked at the last day that intercourse occurred, and determined how many boys and girls were conceived. This is the graph of its findings:

There aren't numbers to indicate how many boys and girls were conceived with BD ending on each of these days; however, the article says 129 pregnancies resulted in a live birth, so there must be at least 129 pregnancies in the graph.

One of the obvious problems with looking at the last day of intercourse to evaluate timing is that BD patterns with a 1 day cut-off (for instance) can be very different. Both the best boy timing method and best girl timing method (in my opinion) have a 1 day cut-off. Yet the results are very different if there is no BD before the cut-off than if there is lots of BD beforehand.

Another problem is that the vast majority of all conceptions (at least by people who are trying to get pregnant) have intercourse the day before or day of ovulation. In this study, there were a total of 192 pregnancies initiated (including those that ended in m/c or stillbirth), and only 12 were from a 3 day or more cut-off (so only 6.25% of all pregnancies). This is similar to what I found in my study: only 38 charts out of 700 had a 3 day or more cut-off (5.4% of all pregnancies). I don't know how many charts had a 2 day cut-off in the study above, but the bars for the graph are significantly lower for 2 days before ovulation than they are for 1 day before ovulation. In my study, I only found 82 charts with a 2 day or more cut-off (11.7% of pregnancies). So, in other words, upwards of 88% of charts in my study had BD ending the day before or day of ovulation (and the percentage was probably similar in the study above). It is difficult to tell anything about timing by looking at the day intercourse ends, since almost all conceptions end on just two days.

A final problem is looking at too few pregnancies. Evaluating the sex ratio based on the last day of intercourse COULD identify whether cut-offs of 2, 3, or 4+ days influences gender. However, since cut-offs of 2 or more days are relatively uncommon, you have to look at a LOT of pregnancies to find very many cut-offs. Even with 700 charts, I still only have 82 cut-off charts in my study. 129 pregnacies is simply too few to be able to evaluate whether cut-offs sway.

As a test, I decided to look at the charts in my study to see if I also found timing of intercourse to have "no influence" if I only looked at the day ovulation ended. Since the study above looked at the last day of intercourse BEFORE ovulation, I left out charts that had BD AFTER ovulation. This is what I found:
- BD ends on O: 116 girl charts, 124 boy charts (sways boy 51.7%)
- BD ends on -1: 63 girl charts, 64 boy charts (sways boy 50.4%)
- BD ends on -2: 25 girl charts, 19 boy charts (sways girl 56.8%)
- BD ends on -3: 15 girl charts, 7 boy charts (sways girl 68.2%)
- BD ends on -4: 6 girl charts, 3 boy charts (sways girl 66.7%)
- BD ends on -5+: 2 girl charts, 5 boy charts (sways boy 71.4%)

If I include the charts with BD the day after ovulation, the results are similar.
- BD ONLY on the day after O: 1 girl chart, 0 boy charts (sways girl 100%)
- BD ends on O: 193 girl charts, 206 boy charts (sways boy 51.6%)
- BD ends on -1: 98 girl charts, 90 boy charts (sways girl 52.1%)
- BD ends on -2: 31 girl charts, 30 boy charts (sways girl 50.8%)
- BD ends on -3: 18 girl charts, 13 boy charts (sways girl 58.1%)
- BD ends on -4: 6 girl charts, 6 boy charts (50/50)
- BD ends on -5+: 3 girl charts, 5 boy charts (sways boy 62.5%)

In both analyses, the only significant result was that 2-3 day cut-offs sway for girl. All other patterns either had too few charts to be significant or had results close to what would be expected from chance. If I was just looking at the day intercourse ended, I would be able to tell that 2-3 day cut-offs swayed, but otherwise it would look like timing had no effect.

In conclusion, I do think timing is important, and I do think some BD patterns sway. However, since most BD patterns don't sway or sway very little, scientific studies are not going to recognize the importance of timing unless they are looking for the handful of BD patterns that influence gender. Simply looking at the last day of intercourse is not an effective way to evaluate whether or not timing sways.

Frequent BD + Testosterone

2010-03-02T04:42:00Z

I've been reading a very interesting book, Heroes, Rogues and Lovers by James McBride Dabbs with Mary Godwin Dabbs, on testosterone. One interesting finding in the book is that people with high testosterone have more sex overall and have more sex with different people. However, while high testosterone is related to greater amounts of sexual activity, it also works the other way around: Having sex also increases testosterone.

One of the most popular timing methods for girls is frequent BD, based on the assumption that more BD lowers sperm count. It may very well be true that lots of BD lowers sperm count. However, as I've studied charts, I have NOT found that frequent BD favors girls. In fact, frequent BD seems to be close to 50/50 or to slightly favor boys. Even extended frequent BD (at least 7 BD times in the 10 days prior to through the day after ovulation) was also pretty close to 50/50, just slightly favoring girls. And the charts with the most BD (12-13 BD times) significantly favored boys (4 boy charts to 1 girl chart).

Before I started looking at charts, I assumed frequent BD would favor girls. It was surprising to find that it didn't. After reading what I have about testosterone, though, I have found a possible explanation. My hypothesis is that frequent BD raises testosterone levels in the dh and dw, and that increase in testosterone (which sways boy) offsets the benefit of lowered sperm count (which sways girl).

Does swaying work?

2010-02-14T00:53:00Z

One of the questions that comes up on the boards all the time is "does swaying work?" These are my thoughts on the subject.

I've read the studies in the FAQ, I've read other information available here and elsewhere online, I've followed information about people's sways, and I've even done my own extensive research into one aspect of swaying (timing). My feeling is that swaying absolutely does "work" (in the sense that it increases your odds of a particular gender). I've seen lots of evidence that various things influence the gender ratio, and I think logically it makes sense that various environmental factors could influence gender.

I do think our knowledge of swaying is incomplete. There isn't a whole lot of research available, and so we don't really know how much various factors sway (does it sway 10%? 5%? 2%?), we may be unaware of some factors that sway, and we might even be wrong about the way certain factors sway. With incomplete information, there is some disagreement about how various factors sway. Some people think the moon sways; others of us are extremely skeptical that it has any influence at all. Some people think frequent BD through ovulation is a great girl swaying method; I think if it sways at all, it sways for boys. Still, despite our incomplete knowledge about swaying, I do believe we have identified a number of things that can influence the gender ratio.

However, I don't really think that swaying is all that effective. The most optimistic odds I have seen anyone give for a perfect sway is 75-80% effective. (The odds might be higher with extreme gender swaying, but since we have so few examples of people who have tried it, it's hard to know for sure.) People with near perfect sways are often stunned when they get an opposite and decide swaying doesn't work. People who see near perfect sways fail have their "faith" in swaying shaken. Personally, I agree with the 75-80% effectiveness rate for a near perfect sway. However, I guess I am different from most people in that I don't see 75-80% as being very good odds.

Look at it this way. The "normal" odds for gender are 50/50. So if you have 4 women who don't sway, 2 should end up with girls (or boys). In contrast, the odds for a near perfect sway are, perhaps, 75%. So if you have 4 women who all have near perfect sways, 3 should end up with girls (or boys). Even with a near perfect sway, the odds of an opposite are 1 in 4. And lots of people don't think perfect sways are even 75% effective.

Here's another way to look at it. I just had a miscarriage at 13 weeks. Two weeks earlier I saw the baby's heartbeat on an ultrasound and saw it move. My odds of having a take home baby at that point were 90-95+%. Those odds were significantly higher than my odds of a having a girl, even if my sway had been a lot better than it was. And yet, my baby still died. Loads of other women also lose their babies in the second and third trimester even when the odds are drastically in their favor. Does this mean doctors are wrong and seeing a heartbeat or reaching various pregnancy milestones have no impact on the chances of a healthy pregnancy? Nope. It just means that sometimes people end up on the unlucky side of the statistics, and it sucks. :(

I suspect the effectiveness of the "average" incomplete sway that most people do is 60-70%. 60% is definitely better than 50%, and if most sways are 60% effective, that means women have increased their odds of getting the gender they desire. Now, instead of having 5 women in 10 having girls (or boys), 6 in 10 will. But people need to keep in mind that neither 60% nor 70% nor even 80% is the same thing as 100%. It is inevitable that there will be opposites with swaying, and it is impossible to judge swaying by looking at a single person's experience. While I do think swaying increases a person's odds, I don't think swaying is even remotely close to a guarantee of one's desired gender.

Ph Study - Volunteers Needed!

2009-10-31T02:39:00Z

One of the things that I've been really interested in since I first learned about swaying is ph. It makes a lot of sense to me that low ph would favor girls and high ph would favor boys. But how much does ph sway? Is it more effective than timing? Less effective? And if your ph is in a specific range (4-5, 6-7, or 8-9, say), how does that specific ph sway?

Unfortunately, ph doesn't appear on FF charts - which is what I've studied in the past - and the information on swaying boards about ph is too anecdotal to be very helpful. Someone might say her ph was "low," but was it really 4-5 her entire fertile period? Did she check every day and how often? Did it ever spike without her knowing? Without carefully keeping track of ph during the entire fertile period, it is difficult to know for sure what the ph was and how it swayed.

So I have decided to try to put together a study of ph. This will be a volunteer study; I will need people who are swaying (or who have swayed) to keep track of their ph and send their information to me. If you would like to be part of the study, this is what I need you to do.

1) You must be an active member of IG. I don't at this time have a definition for "active member" (I will update if/when I come up with a specific definition). While I don't expect you to have 1000s of posts, I do want to avoid including people who are only lurkers. You need to have some minimal level of participation and visibility on IG.

2) You need to keep track of ph from 5 days prior to ovulation through the day afterward. For each of those days I would like at least 4 ph readings spaced throughout the day. If you have more than 4 readings - great! But I would like to see at least 4. For instance, this is the format I would like to see:

5 days prior to ovulation:
- 8:00 am: 4.5
- 1:00 pm: 4.7
- 6:00 pm: 5.0
- 10:00 pm: 4.8

4 days prior to ovulation:
- 8:30 am: 5.0
- 1:00 pm: 5.2
- 5:30 pm: 4.8
- 10:00 pm: 4.9

You don't need to have the exact same amount of time between your readings; I just don't want all the readings to, say, be 1 hour apart in the morning. They should be spaced to reflect your ph throughout the day. If you happen to be missing ph information for the day after ovulation, it is okay to send me the information anyway as I may still be able to use it - but the days prior to and including ovulation are not optional.

One exception: If you are doing just an O+12 and have at least 5 days abstinence prior to ovulation, I only need to have one day's worth of entries on the day of ovulation (that is, at least 4 ph readings on the day of ovulation). Please specify the time(s) you made your O+12 attempt(s) and keep testing ph for 12 hours after that.

3) You need to have a Fertility Friend chart that verifies ovulation based on BBT, and you must send me a link to your chart. In my opinion, OPKs, cm and cervical position are useful for helping to identify ovulation - but BBT is the best method for determining whether ovulation has definitely occurred. Thus you must be verifying ovulation by BBT.

4) You need to let me know how you are testing ph. I would just like to know, as specifically as possible, what ph tester you are using. E.g. Hanna 99104, Colorphast ph strips, etc. Please only send me ph information if you feel confident your ph tester is testing accurately and you are interpreting it correctly.

5) You need to have gotten a BFP on the cycle for which you send me ph information. I don't need ph information for cycles that resulted in BFN. Please also update me if you end up having a miscarriage and/or when you find out gender.

6) You need to let me know if you are swaying for a girl or a boy. If you ph is low, I can guess you are trying for a girl, just like if your ph is high, I'll guess that you are trying for a boy. However, I know that not everyone can get their ph in the right range - and sometimes it spikes or drops and we can't get it back where it is supposed to be. So I do need to know for certain what you were trying for.

One of the big things that distinguishes this study from the one I did on timing is that few if any people in the timing study were swaying whereas everyone in the ph study will be. So this will really be testing how ph affects gender for women who are already swaying. This is why I need to know what you are swaying for. If you are trying for a boy, but you can't raise your ph as high as it should be, you are still more likely to have a boy because of all the other things you are doing to sway. An "average" ph for someone who is swaying for boy is more likely to result in a boy than an "average" ph for someone who is swaying for a girl for reasons other than just the ph - so I will need to account for that when I am analyzing the information.

7) If you would like to send me information about when you did anything that directly affects vj ph - douche, Replens, baking soda finger, etc. - that could be helpful information to have. But if you don't want to send it that is okay, as I will primarily be looking at the ph.

For now, I think this will be adequate information for me to get started on a ph study. However, these requirements are subject to change, as I may find that I need to make changes or request more information as the study progresses.

Thank you very much to anyone who is willing to participate!

How does BD 2 times sway?

2009-10-28T05:01:00Z

So far, I've looked at how 1 BD time, 3 BD times, and 4+ BD times sway, so I figured it was time to look at how 2 BD times sway as well. :)

There were 72 boy charts and 65 girl charts, resulting in a preference for boys of 52.6%. This is the breakdown of the charts.
- 2 non-consecutive times including ovulation: 13 boy charts, 11 girl charts (sways boy 54.2%)
- 2 consecutive times including ovulation and NOT the day after O: 6 boy charts, 14 girl charts (sways girl 70%)
- 2 consecutive times, O and the day after O: 8 boy charts, 2 girl charts (sways boy 80%)
- 2 non-consecutive times including the day after O: 10 boy charts, 7 girl charts (sways boy 58.8%)
- 2 non-consecutive times with a 1 day cut-off: 16 boy charts, 11 girl charts (sways boy 59.3%)
- 2 consecutive times with a 1 day cut-off: 5 boy charts, 3 girl charts (sways boy 62.5%)
- 2 times with a 2 day cut-off: 14 boy charts, 17 girl charts (sways girl 54.8%)

As you can see, most of the patterns with 2 BD times sway boy, and most of those appear to sway boy substantially. There are only two exceptions. One is the pattern with a 2 day cut-off. Not surprisingly, this shows a small preference for girls, as fits with the previous finding that cut-offs in general favor girls.

More surprisingly, 2 consecutive BD times that include ovulation but NOT the day after showed a surprisingly signficant preference for girls. There were two specific patterns in this category:
- the day before and day of ovulation: 5 boy charts, 12 girl charts (sways girl 70.6%)
- twice on the day of ovulation: 1 boy chart, 2 girl charts (sways girl 66.7%)

Since the day before and day of ovulation are typically viewed as prime boy swaying days, I don't know why BD on BOTH those days appears to favor girls. There also aren't that many charts with this pattern (only 20), so I can't really bring myself to suggest this as a good girl swaying pattern. But if you accidentally end up with this pattern, it doesn't look like it's the worst BD pattern for a girl. And if you are swaying for a boy, it appears that it is good to BD on the day before ovulation OR the day of - but not both.

How does extended frequent BD sway?

2009-09-24T03:40:00Z

Another theory I have been interested in testing is whether extended frequent BD - that is, frequent BD for longer than just the 5 days prior to ovulation - favors girls. I know that BD from AF to O is a popular girl timing method. However, I have been skeptical about how effective this would be, since frequent BD shortly before ovulation seems to be pretty close to 50/50. It also seems to me that there are other potential problems with extended frequent BD.

First, it's an awful lot of work. BD every day from AF to O results in a LOT of BD, and a lot more than most people would normally have by choice. It's hard enough to ttc in general, and when you have to BD every day - not just during your fertile window - it makes ttc that much more difficult. Second, because you start BD so early - especially for people who ovulate late - there is an increased chance of "pooping out" right when you get to the most important time. Finally, it seems to me that dealing with the "We have to BD tonight!" feeling for one to two weeks - or even longer in some cases - would be quite stressful. And stress of course, raises testosterone and sways for boys. Swaying is stressful enough as it is; extended frequent BD just seems to me to add to the stress. However, if it works it works, and if extended frequent BD does significantly favor girls, then it might be worth the drawbacks.

To analyze this timing pattern, I had to go back to the original charts I used in order to find timing patterns earlier than 5 days prior to ovulation. There was one little problem with this: I no longer have copies of all the charts used in my study. When I first started this project, I was pretty informal about it. I just looked at the charts on FF and took down notes. By the time I realized that I could - and should - save the charts I was using, a bunch of the charts had already disappeared from the FF chart gallery. Only about 50 charts are missing from my study, but that still poses a problem when I need to get further information from the charts. What I decided to do in this case was simply remove the first 55 boy and 55 girl charts from this part of the study. Not all of those charts are missing, but the missing charts are all from the first 110 charts I looked at. So for this particular theory that I'm testing, I am only looking at the most recent 590 charts.

When I looked at the charts again, I decided to analyze the 10 days prior to ovulation through the day afterwards. I defined extended frequent BD as at least 7 BD times during those 12 days, at least 4 of which had to occur within the 5 days prior to ovulation through the day afterward. 130 charts out of 590 had this pattern, 62 boy charts and 68 girl charts (sways girl 52.3%).
- 7 times: 27 boy charts, 30 girl charts (sways girl 52.6%)
- 8 times: 15 boy charts, 21 girl charts (sways girl 58.3%)
- 9 times: 11 boy charts, 8 girl charts (sways boy 57.9%)
-10 times: 3 boy charts, 5 girl charts (sways girl 62.5%)
-11 times: 2 boy charts, 3 girl charts (sways girl 60%)
-12 times: 2 boy charts, 0 girl charts (sways boy 100%)
-13 times: 2 boy charts, 1 girl chart (sways boy 66.7%)

As you can see, there is a small preference for girls on the extended frequent BD charts, but the overall results are pretty similar. And while there were more girl charts than boy charts, the boy charts had a slightly higher rate of BD: The 68 girl charts had 546 BD times (an average of 8.03 BD times), and the 62 boy charts had 510 BD times (an average of 8.23 BD times).

As usual, the thing that made a difference in whether the extended frequent BD charts swayed for a girl is whether there was BD on the day of ovulation. 50 boy charts and 52 girl charts had BD on ovulation, which results in a slight preference for girls (51%). On the other hand, if the day of ovulation was avoided, it resulted in a stronger preference for girls. 12 boy charts and 16 girl charts avoided BD on the day of ovulation, which results in a 57.1% preference for girls.

Just like with frequent BD shortly before ovulation, extended frequent BD only seems to really favor girls if the BD avoids ovulation. And extended frequent BD doesn't appear to do anything to improve the odds of a girl. In fact, right now frequent BD for the shorter period of time has 59% odds of a girl, which is, obviously, higher than 57.1%.

If you really like BD every day or nearly every day and are enjoying the ttc process, it may not hurt to BD every day from AF to O. But for the rest of us mere mortals, I think it's best to just leave the frequent BD to the five days prior to ovulation. As far as I can tell from looking at FF charts, BD every day for a week or two or three does not appear to significantly raise the odds of getting a girl.

How does BD every other day sway?

2009-09-11T09:46:00Z

For anyone who is interested, our first sway attempt resulted in a BFN, so now I don't have to stress about how I ruined the timing part of my sway. Instead, now I can start stressing about how maybe I'm too old, my eggs are all rotten, and I'm not going to be able to get pregnant. (There's always got to be something to stress about, you know! ) Anyway, since we are still not pregnant, I am still obsessed with analyzing charts, and so today's post deals with another theory I have run across for swaying.

One of the theories I've wondered about is whether BD every other day results in more boys, since gaps of 48 hours or more are supposed to favor boy sperm. So I looked through the 700 charts I have amassed to see how BD every other day sways. In order to have BD every other day, you can only BD 2, 3 or 4 times during the 5 days prior to through the day after ovulation. There were 40 boy charts and 42 girl charts with every other day BD, resulting in a preference for girls of 51.2%.
- 2 times: 23 boy charts, 23 girl charts (50/50)
- 3 times: 16 boy charts, 14 girl charts (sways boy 53.3%)
- 4 times: 1 boy chart, 5 girl charts (sways girl 83.3%)

As you can see, the results were pretty similar except for BD every other day for 4 days. That pattern significantly favored girls (though since there are only 6 charts, the percentage isn't particularly reliable). Part of the reason for this is that there is only one BD pattern possible if you are BD every other day, for 4 times, within the 5 days prior to through the day after ovulation: O-5, O-3, O-1, and O+1. This pattern also counts as frequent BD that avoids ovulation, which as has already been discussed, significantly favors girls. Apparently if you are swaying for a girl, the benefits of frequent BD that avoids ovulation outweighs the risks of BD every other day.

If we omit BD every other day for 4 times, the results are essentially the same as chance (39 boy charts out of 76, sways boy 51.3%). I would still be leery of BD every 48 hours if you are swaying for a girl because of other evidence that BD every 48+ hours favors boys. However, the above information suggests that BD every other day may be another timing pattern that does NOT sway, and so it won't hurt or help your efforts for whatever gender you are hoping for.

There were some aspects of BD every other day that did appear to have an influence on gender. 25 of the charts had BD on the day ovulation: 15 boy charts and 10 girl charts, which results in a preference for boys of 60%. And 11 of the charts had a cut-off of at least 2 days: 4 boy charts, and 7 girl charts, which results in a preference for girls of 63.6%. This suggests that while BD every other day seems to be pretty close to 50/50, it does favor boys if it includes BD on ovulation and it favors girls if the every other day BD has a 2-3 day cut-off.

How does BD 3 times sway?

2009-08-30T22:12:00Z

This month was our first attempt at ttc another dd, and as seems to happen after the best of swaying plans are laid - everything goes awry once you make your first attempt. :) I ovulated 1-2 days earlier than normal, and in fact, in all the time I have been charting, I have only ovulated earlier than this one other time, 3+ years ago. *sigh* (And yeah, I know it would have been smarter to start BD sooner, but I had to keep in mind that 1. I am far, far, far more likely to ovulate late than early, and 2. dh and I are old and tired, lol, and even BD 4 times in a row is a superhuman feat for us to have to accomplish! :) )

So, anyway, I wondered how timing sways if there are only 3 BD times. This is what I found.

There were 91 girl charts, and 83 boy charts, resulting in a preference for girls of 52.3%. This is the breakdown of the charts
- 3 non-consecutive times including ovulation: 31 boy charts, 34 girl charts (sways girl 52.3%)
- 3 consecutive times including ovulation: 6 boy charts, 7 girl charts (sways girl 53.8%)
- 3 non-consecutive times including O and the day after O: 4 boy charts, 7 girls charts (sways girl 63.6%)
- 3 consecutive times including O and the day after O: 3 boy charts, 2 girl charts (sways boy 60%)
- 3 non-consecutive times ending before O: 23 boy charts, 26 girl charts (sways girl 53.1%)
- 3 consecutive times ending before O: 4 boy charts, 6 girl charts (sways girl 60%)
- 3 non-consecutive times with NO BD on O but WITH BD the day after O: 12 boy charts, 9 girl charts (sways boy 57.1%)

As you can see, there is a small preference for girls, but it is only about 3-4%. (The few high percentages are due solely to having small numbers of charts available for those patterns, and the percentages are not reliable for that reason.) Here are some other ways to look at the numbers.
- the BD includes ovulation: 44 boy charts, 50 girl charts (sways girl 53.2%)
- the BD doesn't include ovulation: 39 boy charts, 41 girl charts (sways girl 51.25%)
- the BD is non-consecutive: 70 boy charts, 76 girl charts (sways girl 52.1%)
- the BD is consecutive: 13 boy charts, 15 girl charts (sways girl 53.6%)
- BD includes the day after ovulation: 19 boy charts, 18 girl charts (sways boy 51.4%)
- BD doesn't include the day after ovulation: 64 boy charts, 73 girl charts (sways girl 53.3%)

Note: It may seem a bit odd that girls are favored for everything except for BD that includes the day after ovulation. But the reason for this is simply that there are more girl charts in this sample. Since the results for everything are close to 50/50, almost all of the patterns slightly favor girls.

The moral of the story is that if you are planning frequent BD to sway for a girl, it is best to start too early rather than too late (assuming both you and your partner can keep up with the BD schedule!). If you try for frequent BD and get cut short by early ovulation - even by just one day - it does significantly reduce your timing odds for getting a girl. This is yet another reason why it is good to do several effective things to sway. You won't screw up your whole sway if you mess up one part! ;)

Update: Does frequent, consecutive BD favor girls?

2009-08-24T03:04:00Z

With the additional 200 charts, frequent consecutive BD is now showing a small preference for girls - but it still appears to be a much less effective girl timing method than others we have looked at.

Frequent, consecutive BD is defined as charts where the BD ended with at least 4 consecutive BD times. So, for instance, if a chart had 5 BD times, starting with 1 day of BD, followed by a gap of one day, followed by 4 days with BD every day, it was included. But if it started with 2 days of BD, followed by a gap of one day, followed by 3 days with BD, it was not included. Also, I counted multiple BD times during one day as separate BD times. So I included charts that had, for instance, 1 day with 1 BD time, followed by a day with 2 BD times, followed by a day with 1 BD time.

There was a small preference for girls on the charts with frequent, consecutive BD. There were 57 boy charts and 66 girl charts with this pattern, resulting in a preference of 53.7% for girls.
- 4+ consecutive BD times: 57 boy charts, 66 girl charts (sways for girl 53.7%)
- 5+ consecutive BD times: 34 boy charts, 37 girl charts (sways for girl 52.1%)
- 6+ consecutive BD times: 21 boy charts, 19 girl charts (sways for boy 52.5%)
- 7+ consecutive BD times: 10 boy charts, 12 girl charts (sways for girl 54.5%)

And here are the actual numbers of charts that had 4, 5, 6, etc. BD times on them:
- 4 consecutive BD times: 23 boy charts, 29 girl charts (sways girl 55.8%)
- 5 consecutive BD times: 13 boy charts, 18 girl charts (sways girl 58.1%)
- 6 consecutive BD times: 11 boy charts, 7 girl charts (sways boy 61.1%)
- 7 consecutive BD times: 7 boy charts, 9 girl charts (sways girl 56.25%)
- 8 consecutive BD times: 2 boy chart, 3 girl charts (sways girl 60%)
- 9 consecutive BD times: 1 boy chart, 0 girl charts (sways boy 100%)

While frequent, consecutive BD favors girls, the degree to which it does so decreases if we look at just the charts that had BD on ovulation. Of these frequent, consecutive BD charts, 53 boy charts and 57 girl charts had BD on the day of ovulation, resulting in a 51.8% preference for girls. This IS a percentage that is greater than chance, but it's not a whole lot greater.

Frequent consecutive BD that avoids ovulation still favors girls, but to a much smaller degree than it did previously. 4 boy charts and 9 girl charts in the study had this pattern, which results in a 69.2% preference for girls.

Update: Does frequent BD that avoids ovulation favor girls?

2009-08-23T07:59:00Z

Even though frequent BD through ovulation is pretty much 50/50 overall, frequent BD that AVOIDS ovulation does appear to favor girls.

Once again, frequent BD is defined as at least 4 BD times between 5 days prior to ovulation through the day afterward but NO BD on the day of ovulation itself. There were 83 charts with this pattern: 49 girl charts and 34 boy charts, which results in a 59% preference for girls.
- 1 day cut-off: 8 boy charts, and 18 girl charts (sways girl 69.2%)
- 2 day cut-off: 2 boy charts, and 2 girls charts (50/50)
- 1 day cut-off and day after ovulation: 19 boy charts, and 26 girl charts (sways girl 57.8%)
- 2 day cut-off and day after ovulation: 4 boy charts, and 3 girl charts (sways boy 57.1%)
- 3 day cut-off and day after ovulation: 1 boy chart, and 0 girl charts (sways boy 100%)

What is apparent from looking at how the charts break down is that the charts that did not have BD the day after ovulation favored girls to a much stronger extent (10 boy charts and 20 girl charts, favors girls 66.7%) than the charts that had BD the day after ovulation (24 boy charts and 29 girl charts, favors girls 54.7%).

Even though I have been repeating this throughout the blog, I will say it yet again: I do NOT think this means that a cut-off and O+12 favors boys. As I've said previously, the FF charts do not tell when ovulation actually occurred, so it is impossible to tell whether any BD times on them are O+12. I suspect that the reason there are more boy charts that had BD the day after ovulation is because in some cases ovulation occurred late on the day of ovulation and the BD happened early the next day, and so the BD the "day after ovulation" was really in boy timing.

While frequent BD that avoids ovulation favors girls overall, it sways for girls the most if the 4+ days of frequent BD all occur prior to ovulation. In fact, the current effectiveness rate for this pattern (66.7%) is now running higher than the current effectiveness rate for cut-offs (60.6% for 2-3 day cut-offs). Also, the big plus with this pattern is that it should not significantly reduce the odds of getting pregnant.

Update: Does frequent BD favor girls?

2009-08-22T23:04:00Z

After adding another 200 charts, frequent BD continues to be a 50/50 timing pattern - however, it does sway for either boys or girls depending on whether the frequent BD includes the day of ovulation.

Overall the amount of BD on boy and girl charts is very similar. There were 1220 BD times on the 350 boy charts (average of 3.49 BD times on the boy charts). There were 1253 BD times on the 350 girl charts (average of 3.58 BD times on the girl charts).

Since there is no set definition for frequent BD, I chose to define it as at least 4 BD times during the five days prior to ovulation through the day afterwards. 321 charts out of the 700 I looked at followed this pattern, 159 girl charts and 162 boy charts (162/321, sways boy 50.5%).

Frequent BD charts:
- 4 BD times: 74 boy charts, 69 girl charts (sways boy 51.7%)
- 5 BD times: 51 boy charts, 47 girl charts (sways boy 52%)
- 6 BD times: 23 boy charts, 28 girl charts (sways girl 54.9%)
- 7+ BD times: 14 boy charts, 15 girl charts (sways girl 51.7%)

Even though the numbers for frequent BD through ovulation are pretty close to 50/50 for boys and girls, there is one significant detail that makes a difference in how the BD sways: whether there is BD on the day of ovulation. 205 charts with frequent BD had BD on the day of ovulation, 111 boy charts and 94 girl charts, resulting in a 54.1% preference for boys.

If the day of ovulation is avoided in frequent BD, though, the preference is for girls. 83 charts followed this pattern, 34 boy charts and 49 girl charts, resulting in a 59% preference for girls.

Previously, I said that I didn't think frequent BD through O was the worst swaying method for a girl (and technically it still isn't - there are definitely worse timing methods to use, lol!). However, after looking over the statistics again, I do think frequent BD through ovulation is a worse timing method than I used to think. Before I simply thought that it was 50/50, and that it was better to go with a timing method that actually sways, since there are timing patterns that DO produce more girls and that don't significantly decrease the chance of pregnancy. But in fact, if the frequent BD includes the day of ovulation it is NOT 50/50; it actually sways 54.1% for boys. Obviously, this is not a huge preference for boys, and it is only about 3% more than chance. But it does result in more boys.

It does surprise me that frequent BD that includes the day of ovulation is not just 50/50. BD on ovulation in general is running close to 50/50 and one would think that, since frequent BD lowers sperm count, frequent BD at the very least should have the same odds as BD on ovulation in general. I have no theories at this time to explain why frequent BD through ovulation would result in MORE boys that nonfrequent BD through ovulation. If I come up with some explanation, I will update.

Update: Do cut-offs favor girls?

2009-08-21T02:16:00Z

After looking at another 200 charts, cut-offs still favor girls - but the effectiveness rate for cut-offs has decreased.

Overall, there were 34 boy charts and 48 girl charts with cut-offs, which results in a preference for girls of 58.5%.
- 2 day cut-off: 19 boy charts, 25 girl charts (sways girl 56.8%)
- 3 day cut-off: 7 boy charts, 15 girl charts (sways girl 68.2%)
- 4 day cut-off: 3 boy charts, 6 girl charts (sways girl 66.7%)
- 5 day cut-off: 3 boy charts, 1 girl chart (sways boy 75%)
- 6 day cut-off: 2 boy charts, 0 girl charts (sways boy 100%)
- 7 day cut-off: 0 boy charts, 1 girl chart (sways girl 100%)

Short cut-offs (2-3 days) have a 60.6% effectiveness rate overall, and 3 day cut-offs appear to be the most effective at 68.2%. However, part of the reason why 3 day cut-offs may appear to sway more for girls is because a "2 day cut-off" on the FF charts may really be a less than 48 hour cut-off - if BD took place in the evening and if ovulation occurred in the morning. I still think a 2 day (that is, 48 hour) cut-off is a good timing method.

I also kept track of charts that had a 2+ day cut-off, followed by BD the day after ovulation. (Again, please keep in mind that this is NOT the same thing as a cut-off and an O+12. BD the day after ovulation may mean an O+12 - but it may also mean that the BD happened within 12 hours of ovulation if ovulation occurred late in the day on the "day of ovulation," or it may mean the BD occurred long after the egg had died.) There were 20 boy charts and 10 girl charts with this pattern, resulting in a 66.7% preference for boys.
- 2 day cut-off w/BD 1 day after ovulation: 11 boy charts, 6 girl charts (sways for boy 64.7%)
- 3 day cut-off w/BD 1 day after ovulation: 6 boy charts, 3 girl charts (sways for boy 66.7%)
- 4 day cut-off w/BD 1 day after ovulation: 3 boy charts, 0 girl charts (sways boy 100%)
- 5 day cut-off w/BD 1 day after ovulation: 0 boy charts, 1 girl chart (sways girl 100%)

Alas, while these are some of the highest effectiveness rates I have found for boys I cannot recommend a cut-off and then BD the day after ovulation to sway for a boy, lol! The reason, of course, is that I don't know exactly when ovulation is occurring or when BD is occurring so I don't know WHY this pattern is producing such a high rate of boys. What it may suggest is that BD within 12 hours after ovulation favors boys if the most recent previous BD took place 3-5 days before. This would fit with other scientific evidence discussed on IG. But that is the best hypothesis I can come up with to explain the pattern.

One more notable thing about cut-offs is that they are not a particularly good way to get pregnant. Only 82 charts out of 700 (11.7%) had a cut-off. Only 16 charts (2.3%) had a cut-off of 4 or more days.

Update: Does one-time BD favor boys?

2009-08-20T02:32:00Z

For as long as I've been doing this study, I've been finding similar numbers of boy and girl charts with one-time BD. Usually there are slightly more boy charts, but after looking at these last 200 charts, I now have slightly more girl charts. 35 girl charts had one-time BD, and 33 boy charts had one-time BD, which results in a 51.5% preference for girls (35/68 charts).

However, what was significant was the day the one-time BD occurred on.
- 1 day after ovulation: 0 boy charts, 1 girl charts (sways girl 100%)
- on the day of ovulation: 7 boy charts, 6 girl charts (sways boy 53.8%)
- 1 day before ovulation: 15 boy charts, 8 girl charts (sways boys 65.2%)
- 2 days before ovulation: 2 boy charts, 7 girl charts (sways girl 77.8%)
- 3 days before ovulation: 2 boy charts, 5 girl charts (sways girl 71.4%)
- 4 days before ovulation: 2 boy charts, 6 girl charts (sways girl 75%)
- 5 days before ovulation: 3 boy charts, 1 girl chart (sways boy 75%)
- 6 days before ovulation: 2 boy charts, 0 girl charts (sways boy 100%)
- 7 days before ovulation: 0 boy charts, 1 girl chart (sways girl 100%)

Again, a lot of these statistics are questionable because there aren't many charts with one-time BD. However, there is a general trend where BD the day of ovulation or 1 day prior favors boys (22/36, sways boy 61.1%), BD 2-4 days prior to ovulation favors girls (18/24, sways girl 75%), and BD 5+ days prior to ovulation favors boys (5/7, sways boy 71.4%). One-time BD does seem to sway - but how it sways depends on what day the BD occurred on.

One-time BD is also not the best way to get pregnant. Out of 700 charts only 68 (9.7% of the charts) had just a single time of BD.

Update: Does BD on ovulation favor boys?

2009-08-20T01:05:00Z

I've analyzed another 200 charts (100 boy charts and 100 girl charts) since I last posted. I am keeping track of these charts separately from the 500 I originally looked at since I want to see - once I've looked at another 500 charts - if I get similar results to what I found with the first 500. However, I thought I could still update each of the theories I was testing so people could see how these new charts affected my past findings.

What I found previously for BD on the day of ovulation is that it slightly sways for boys, but the numbers are pretty much the same as chance. Those findings are still the same after looking at another 200 charts.

A majority of all charts - for boys and girls - had BD on the day of ovulation.
- 207 boy charts out of 350 (59.1% of all boy charts had BD on ovulation)
- 192 girl charts out of 350 (54.9% of all girl charts had BD on ovulation)

Out of 399 total charts with BD on the day of ovulation, boys resulted 51.9% of the time (207/399 charts) and girls resulted 48.1% of the time (192/399 charts). While this technically results in more boys, the findings are essentially the same as chance (since the natural birth rate is 51% boys, and 49% girls). It indicates that simply BD on the day of ovulation does not sway.

One thing that does sway a little bit is the kind of cm present on the day of ovulation. If there is ewcm (eggwhite OR watery cm) on the day of ovulation, boys are a little more likely to result.
- 152 boy charts out of 281 charts w/ewcm on ovulation (54.1%)
- 129 girl charts out of 281 charts w/ewcm on ovulation (45.9%)

If there is NOT ewcm present (if it is sticky or creamy, or there is no cm present), girls are a little more likely to result.
- 55 boy charts out of 118 charts with NO ewcm on ovulation (46.6%)
- 63 girl charts out of 118 charts with NO ewcm on ovulation (53.4%)

Still the influence of cm has dropped as I've continued to look at more charts and the results aren't substantially different from chance.

So what does all this mean for swaying? BD on ovulation in no way guarantees a boy, and it doesn't ruin the chances of having a girl. A majority of all charts have BD on ovulation, and simply BD on ovulation results in odds of a particular gender that are essentially the same as chance. Just BD on ovulation in general seems to have little to no impact on the gender that results.

More on frequent BD that avoids ovulation

2009-07-13T07:25:00Z

Since I've gotten some questions about the "frequent BD that avoids ovulation" timing method, I thought I would look a little closer into which charts that followed this pattern seemed to work best for girls.

Again, this pattern is defined as at least 4 BD times between 5 days prior to ovulation through the day afterward but NO BD on the day of ovulation itself. There were 58 charts with this pattern: 33 girl charts, and 25 boy charts, which results in a 56.9% preference for girls. (If you've been following this blog, you may have noticed that this is a different total than I gave previously. Yup, even though I double and triple check this information before sharing it with people, I'm still capable of goofing up and losing 11 charts. *sigh* At least the error is fixed now.)

- 1 day cut-off: 3 boy charts, and 13 girl charts (sways girl 81.25%)

- 2 day cut-off: 1 boy chart, and 2 girl charts (sways girl 66.7%)

- 1 day cut-off and day after ovulation: 17 boy charts, and 16 girl charts (sways boy 51.5%)

- 2 day cut-off and day after ovulation: 4 boy charts, and 2 girl charts (sways boy 66.7%)

What is obvious from looking at how the charts break down is that the charts that did not have BD the day after ovulation clearly favored girls (4 boy charts and 15 girl charts, favors girls 78.9%), and the charts that had BD the day after ovulation favored boys (21 boy charts and 18 girl charts, favors boys 55.3%).

Please note that I do NOT think this means that a cut-off and O+12 favors boys. As I've said before, the FF charts do not tell when ovulation actually occurred, so it's impossible to tell whether any BD times on them are O+12. I suspect that the reason there were more boy charts that had BD the day after ovulation is because in some cases ovulation occurred late on the day of ovulation and the BD happened early the next day and so the BD the "day after ovulation" was really in boy timing.

If BD "the day after ovulation" is avoided, frequent BD that avoids ovulation favors girls very strongly. Unfortunately, there are fewer than 20 charts with this pattern so the effectiveness rate is probably quite a lot lower than the 78.9% it is showing right now. However, despite the uncertainty about exactly how effective this timing method really is, I still feel comfortable enough with it that it is the one I plan to use in my sway.