The study does not say what you claim. Perhaps you should observe the first rule of holes.
Another reference I had reviewed awhile ago.
https://web.archive.org/web/20220120105856/http://before-i-do.org/
The takeaway:
“Consider sex. The vast majority of Americans—about 90 percent—have sex before marriage (Finer, 2007). Many of them have sex with multiple partners before finding the person they will eventually marry. Do premarital sexual relationships relate to later marital quality? Yes and no. It depends on who you are having sex with. Men and women who ONLY slept with their (future) spouse prior to marriage reported higher marital quality than those who had other sexual partners as well. Further, FOR WOMEN, having had fewer sexual partners before marriage was also related to higher marital quality. This doesn’t mean that sex before marriage will doom a marriage, but sex with many different partners may be risky if you’re looking for a high-quality marriage.”
The other studies I have seen have shown higher number of sex partners for women increase divorce chances. Pair bonding damage.