[Mrs. Don-o]

You wrote: "I have to wonder though, if this isn't part of the problem with the western world not producing at even CLOSE to replacement rate though."

Bingo.

In The Decline of Males, Lionel Tiger discusses various studies (some of which he did) on the effect of the Pill on male libido. In brief, the argument is that since the Pill imitates pregnancy, it changes the production of pheromones and so on by women, which makes them less attractive to men. He suggests that the increase in the wearing of revealing clothing and explicitly alluring behavior in the last part of the 20th century was a compensation for this chemically-induced decrease in natural "sexiness."

[Old Professer]

I thought this thread was going to be about wearing overshoes.

[Mrs. Don-o]

wait a sec--- here's a study that showed that while normally women are attracted to men who have a radically different immune set up (communicated pheromonally), women on the pill are attracted to men with a too-similar make up, and going on or off the pill can thereby disrupt a long standing relationship.

Here's the relevant portion from Psychology Today

(http://cms.psychologytoday.com/articles/pto-1174.html):

The Swiss researchers found that women taking oral contraceptives (which block conception by tricking the body into thinking it's pregnant) reported reversed preferences, liking more the smells that reminded them of home and kin. Since the Pill reverses natural preferences, a woman may feel attracted to men she wouldn't normally notice if she were not on birth control--men who have similar MHC profiles.

The effects of such evolutionary novel mate choices can go well beyond the bewilderment of a wife who stops taking her contraceptive pills and notices her husband's "newly" foul body odor. Couples experiencing difficulty conceiving a child--even after several attempts at tubal embryo transfer--share significantly more of their MHC than do couples who conceive more easily. These couples' grief is not caused by either partner's infertility, but to an unfortunate combination of otherwise viable genes.

Doctors have known since the mid-1980s that couples suffering repeated spontaneous abortions tend to share more of their MHC than couples for whom pregnancies are carried to term. And even when MHC-similar couples do successfully bring a pregnancy to term, their babies are often underweight.

The Swiss team believes that MHC-related pregnancy problems in humans are too widespread to be due to inbreeding alone. They argue that in-couple infertility problems are due to strategic, unconscious "decisions" made by women bodies to curtail investment in offspring with inferior immune systems--offspring unlikely to have survived to adulthood in the environments of our evolutionary past.

(There are also studies that show that women on the Pill put out less pheromones then women who aren't, and so may be less attractive)