Did PMS Evolve In Order To Split Up Infertile Couples?

Did PMS Evolve In Order To Split Up Infertile Couples?

Premenstrual syndrome (or PMS as it is more commonly known) is a catchall term for any unpleasant physical and psychological symptoms a woman might experience just prior to getting her period. Research suggests that as many as 80% of women experience PMS; however, the nature and severity of the symptoms varies dramatically across individuals [1]. On the surface, PMS might not appear to be an adaptive trait, especially considering that, at least for a very small percentage of women, the symptoms are so severe as to become debilitating (in which case it may be referred to as premenstrual dysphoric disorder, or PMDD). But if PMS is so widespread, is it possible that perhaps it came to exist for some evolutionary reason? That’s what Dr. Michael Gillings argues in a controversial new paper just published in Evolutionary Applications [2].

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Hijacked By STIs: Infections That Spread By Increasing The Host’s Interest In Sex

Hijacked By STIs: Infections That Spread By Increasing The Host’s Interest In Sex

Bacteria and viruses are crafty little organisms. They need to be spread quickly from host to host in order to survive, so they tend to evolve in ways that ensure fast and efficient transmission. Sexually transmitted infections (STIs) are no exception. Consider this: part of the reason STIs are so widely spread in humans is because many infections (e.g., chlamydia, gonorrhea, HIV) take weeks or months (or even longer) for symptoms to set in, but during that entire period of time, the host remains highly infectious. For an STI to be spread even faster, all it would have to do is capitalize on this asymptomatic period by working as an aphrodisiac and increasing the host’s desire for sex. Although I am not aware of any research suggesting that STIs increase libido in humans to help them infect even more people, research has found an STI in crickets that seems to do something like this.

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Sex Question Friday: Do STDs Affect Women's Ability To Reach Orgasm?

Every Friday on the blog, I answer people’s questions about sex, love, and relationships. This week’s question comes from a college student who wanted to know whether having a sexually transmitted disease (STD) can interfere with a woman’s sexual pleasure.

If you happen to contract an STD, is it more difficult to induce a female orgasm?

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