I remember looking at these statistics before, and one of the issues with the numbers was that they weren't being careful about counting the number of sexual partners before (as opposed to after) the woman's first marriage.
For example, if we have woman #1, who gets married at 20, who has had no pre-marriage sexual partners (or maybe she just slept with her future husband) and is still married. She gets counted as "near-virgin bride".
Then let's take woman #2. She has a similar situation (no sex before marriage or only slept with her future husband before marriage). She gets married, then divorced, then gets into the dating scene and sleeps with a handful of guys. Now, they count all of her sexual partners (including her post-marriage sexual partners) in their numbers. Then, the higher number count and the divorce are talked about as if the higher-partner-count helped cause the divorce, but it was actually the opposite way around.
In fact, there's an article that often cited by the RedPill as evidence that more sexual partners increase the divorce rate. They often cite these charts as evidence:
http://3.bp.blogspot.com/-QPnsHoU2Pz...0/Heritage.jpg
(This is one of the charts cited in the original post.) The problem with this chart is obvious. It measures the percent of women in stable marriages at the age of 30 compared to their number of sexual partners. It's not measuring divorce rates. Imagine woman #1 who gets married early and is still married. She's counted as "still in a stable marriage and has low partner count". Imagine woman #2. She's 30 years old, has never been married, and has had a number of boyfriends over the past 10+ years that she's been sexually active. She's counted as "not in a stable marriage" and "higher partner count". Obviously, you can see the problem here - the fact that she's been single her entire life means that she's had time to have multiple different relationships and have sex with a number of different men. Woman #1 wasn't in a position to do that unless she's going to be unfaithful to her husband.
In short - the chart has too many variables going on to draw any real conclusions.
Chart#2:
http://1.bp.blogspot.com/-4uvCNpBV-P...640/linear.jpg
At least this one is limited to women who have been "married at least once". The problem is that they're counting total sex partners (including post-divorce sexual partners). Of course women who have had a divorce are more likely to have a higher sexual partner count -- quite a few of those sexual partners occurred after her divorce. Again, I can't draw any real conclusions about how "premarital sexual partner count" affects divorce rate.
Chart #3. Now this chart actually attempts to compare the number of pre-marital sexual partners to the divorce rate. I should note that I've seen the first two charts cited on the RedPill, but the third one is omitted. I consider that to be an example of bias because the 3rd chart is actually the most straightforward about telling us what's going on, but it's also the least (of the three) in agreement with the "high pre-martital sex partners increases chances of a divorce" theory.
http://3.bp.blogspot.com/-BUQXGYyTqy...640/UShape.jpg
What's interesting about this chart is that virgin brides are least likely to divorce. However, it get complicated once you get past virgin brides. As you can see, the risk of divorce follows this pattern:
•Highest Risk: Women with 2 sexual partners.
•Women with 21+ sexual partners.
•Women with 1 marital sexual partner
•Women with 3-20 sexual partners.
•Lowest Risk: Virgin Brides.
It's sort of bizarre. If your goal is to reduce your divorce risk, and you can't/won't marry a virgin, then marry a woman with 5-9 past sexual partners.
There are, of course, some other issues going on. I would suspect that maybe a reason virgin brides are less likely to divorce is because they come from very religious backgrounds, where divorce is frowned on, or where the women start having children quickly (which might cause a woman to be less likely to attempt a divorce, for fear that she would have to manage the work and expense of raising the children on her own). Clearly, we would expect some differences in the cultural backgrounds of the virgin brides compared to other women. The article suggests that maybe women with 5-9 sexual partners is more stable (than other non-virgin women) because it's correlated with the age when women get married. Getting married too young is a divorce factor. If I remember right, divorce rates are lowest when the woman getting married is around 25 years-old and has a college degree. The time-gap between becoming sexually active and getting married would likely result in a partner count above 2. I also can't help but wonder if women with 21+ sexual partners have other correlations going on - for example, sometimes when women are sexually abused as children, they become very sexual in adulthood. Being sexually abused as a child is also a risk factor for getting divorced later in life.