Even though I found no evidence that frequent BD favors girls, I thought that perhaps if the BD was consecutive - that is, if there was BD at least once every day - that that pattern might favor girls. So I looked at all the charts where the BD ended with at least 4 consecutive BD times, to see if frequent, consecutive BD favored girls.
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 40 boy charts and 45 girl charts with this pattern, resulting in a preference of 52.9% for girls.
- 4+ consecutive BD times: 40 boy charts, 45 girls (sways for girl 52.9%)
- 5+ consecutive BD times: 26 boy charts, 27 girl charts (sways for girl 50.9%)
- 6+ consecutive BD times: 16 boy charts, 13 girl charts (sways for boy 55.2%)
- 7+ consecutive BD times: 7 boy charts, 9 girl charts (sways for girl 56.25%)
And here are the actual numbers of charts that had 4, 5, 6, etc. BD times on them:
- 4 consecutive BD times: 14 boy charts, 18 girl charts (sways girl 56.5%)
- 5 consecutive BD times: 10 boy charts, 14 girl charts (sways girl 58.3%)
- 6 consecutive BD times: 9 boy charts, 4 girl charts (sways boy 69.2%)
- 7 consecutive BD times: 5 boy charts, 7 girl charts (sways girl 58.3%)
- 8 consecutive BD times: 1 boy chart, 2 girl charts (sways girl 66.6%)
- 9 consecutive BD times: 1 boy chart, 0 girl charts (sways boy 100%)
While it appears that frequent, consecutive BD favors girls to a small degree, this appearance disappears if we look at just the charts that had BD on ovulation. Of these frequent, consecutive BD charts, 39 boy charts and 38 girl charts had BD on the day of ovulation, resulting in a 50.6% preference for boys - which is basically the same as chance.
On the other hand, if we look at the charts with frequent, consecutive BD that AVOIDS ovulation, the numers are startling. 1 boy chart and 7 girl charts followed this pattern, which results in an 87.5% preference for girls.
It seems that - like frequent BD in general - frequent, consecutive BD is pretty much 50/50 if the frequent BD includes the day of ovulation. However - again like frequent BD in general - if ovulation is avoided, frequent consecutive BD appears to favor girls, possibly by a significant amount.
(Note: I do not believe that frequent, consecutive BD that avoids ovulation is anywhere close to 90% effective at swaying for girls. However, I do think it may be another effective girl swaying technique and will explore this pattern further in my next post.)