When I started my biology degree at Nottingham, I wasn’t interested in learning too much about human biology. I figured I knew what was necessary and I’d let the doctors do the rest while I focused on the more fluffy and scaly aspects of the natural world. However, on sitting through lectures on human behaviour and ecology, I slowly began to see how we humans are not so different to our animal cousins and how modern science can affect our natural instincts in surprising ways. One such phenomenon describes the effects of the contraceptive pill on our ‘mate’ choices and how this can sway the longevity and happiness of relationships.
A woman’s preference for partners has been shown to be influenced by the stages of her menstrual cycle, with ovulating women subconsciously seeking ‘good genes’ in men to maximise the success of potential offspring. ‘Good’ genetic features can include more masculine and symmetrical features as well as dominant behaviour and even decreasing genetic relatedness to herself (sometimes cued by odour!).
Conversely, when at other stages in the cycle, women lose this increased preference for masculine men and will even prefer the odour of genetically similar men. This can be predicted as a preparation for pregnancy, perhaps seeking ‘good fathers’ with milder dispositions and possibly part of her familial group.
How the pill may change a lady’s Prince Charming
Obviously, the ‘good genes’ and ‘good father’ explanations hark back to a time where this distinction was more important, where masculine men had more successful sons but had a degree of aggression that made for poor long-term partnership. This may be behind the times for this modern age but there are many examples where our biology has not caught up with society as we know it, and this can be particularly stark when we add modern medicine into the mix.
“On stopping her use of the pill a woman might find her attraction to a long-term partner, chosen while on the pill, changing and might feel tempted away“
Daily use of the contraceptive pill mimics the hormonal state of pregnancy, increasing the levels of oestrogen and progesterone in a women’s body. This stops the body from cycling as normal and seems to freeze a women’s mate preferences at those expressed when she is not ovulating. Studies have shown no marked preferences by pill users for masculine characteristics and a distinct preference towards genetically similar men. This can be viewed as beneficial, with long-term relationships being theoretically more stable as a women’s attraction to her partner can be more constant and satisfying.
Whilst the contraceptive pill’s effect may benefit long term relationships, this effect can, however, also have downsides. On stopping her use of the pill a woman might find her attraction to a long-term partner, chosen while on the pill, changing and might feel tempted away.
The pairing of genetically similar parents, as is common with contraceptive use, can also lead to future health issues in their children although more study in this area is required to accurately assess the risks.
How the pill may change how the women are viewed by men
It isn’t just a woman’s preference that changes over her menstrual cycle and with pill use, it is also her appeal to potential partners. Women seem to see an increase in attractiveness when ovulating through changes to odour, physical appearance and voice tone as well as acting and dressing more provocatively.
“These recent studies into its effects on behaviour and mate choice may, and should, affect its use into the future”
This change in attraction is very hard to quantify numerically but some out-of-box thinking by scientists at the University of New Mexico found a way using information gathered from lap dancers. On recording tips per shift and comparing these to the dancer’s cycle stages, the researchers found a peak during ovulation (with an average of $185 normally compared to $335 during estrus). This change was not seen in dancers using hormonal contraceptives, who received fewer tips across a month without the fertile peak.
With its side effects and modification of the ‘natural’ cycle of a woman, there has been much debate about hormonal contraceptive use over the years. These recent studies into its effects on behaviour and mate choice may, and should, affect its use into the future. There are, however, clear benefits to the freedom it brings and the medical conditions it alleviates so no-one is suggesting ‘au-naturelle’ is the best approach either.
There are numerous factors that go into a healthy and happy relationship so I wouldn’t panic too much about a freaky mind control drug affecting who you might have invited back at the end of a night out, it might even be helping you make a more ‘clear-headed’ decision!
Image courtesy of Annabelle Schemer via Flikr
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