Birth Control Increases Out-of-Marriage Pregnancies

Here is a puzzle: if promiscuity has increased over the past century and if the cause of that increase was really a fall in the risk of pregnancy, then why have out-of-marriage births increased as well?

Over the whole of the twentieth century premarital sex rates for women increased; from 6% in 1900 to 75% in 1999.* Before the turn of the century, the only really safe form of sex, in terms of risk of pregnancy, was sex within marriage. As new technologies appeared, premarital sex became less "costly" and, as we know, when the price of anything falls, we demand more of it.

The only problem is that the share of all pregnancies that are outside of marriage hasn’t fallen; they have increased from 2% in the 1920’s to 33% in the 1999.

Clearly this isn’t simply a case of individuals weighing the benefit against cost of their behavior; there has to be more to the story.  I would argue that advances in birth control technology might have started the quake, but it was the tidal wave of social change that has really made the difference.

For most of human history the only way to have sex and avoid pregnancy was coitus interruptus—aka withdrawal. Condom use appears to go back 3,000 years but it wasn’t until 1844 when techniques were available to vulcanize rubber, that anything was produced that you might actually want to put on your penis. Even that is questionable, as the original condoms were re-usable and (apparently) uncomfortable.

Speaking of discomfort, it is said that Casanova used lemons cut in half in the way that the modern diaphragm is used, the invention of which had to wait until 1882.

The IUD was invented in 1909 and latex condoms were produced in 1912 making them, thankfully, disposable. As most of us already know, the birth control pill arrived on the market in 1960.

Given that technology for controlling fertility was advancing so quickly over the end of the nineteenth and the beginning of the twentieth century, it isn’t surprising that those who had been cautious about engaging in pre-marital sex began to "enter the market," so to speak. If everyone was making their decisions based solely on pregnancy risk, we would never have seen the increase in pregnancy outside of marriage; in fact, we might have expected to see it fall. Birth control is part of the story, certainly, but the effect is not just that the behavior of pregnancy-minimizing individuals changed.

The story is that when enough pregnancy-minimizing individuals changed their behavior, pre-marital sex became more and more acceptable and others, presumably not minimizing their risk for pregnancy outside of marriage, followed suit. The effect is advances in birth control technology plus social change.

Think of it another way. Let’s say it is 1900 and assume that everyone wants to have sex regardless of whether or not they are married. There is little birth control available, so that if you have sex there is a very good chance (about 85%) that you will get pregnant, even if withdrawal is used (22%). Also, having sex outside of marriage is heavily stigmatized. In fact, for a woman having premarital sex might make it difficult for you to ever marry in the future because it sends a bad signal to any future husband regarding your ability to be faithful.

Now birth control is available and, while it is still stigmatized, a small number of people willing to break the social norm start being more adventurous, presumably those that care more about pregnancy and less about the stigma. Over time the number of people in that promiscuous group increases and the behavior becomes more and more socially acceptable. Others begin to enter the group not because pregnancy risk has decreased but because the costs related to stigmatization are falling.

There is a chance of pregnancy any time two people have sex. As the share of sexual "events" that are between two people who are not married increases, the share of pregnancies in that situation is bound to increase. Add to that the fact that the availability of birth control has also decreased the total number of pregnancies within marriage; the rise in the share of pregnancies outside of marriage was mathematically inevitable.

So is the invention of the birth control pill responsible for the rise in out-of-marriage pregnancies? Well, not really. The effect of one particular contraceptive is quite small. Economists have estimated that less than 1% of the increase in pre-marital sex among teenagers is the result of the invention of the pill.* It isn’t that contraceptives are not important; it's just that the pill is just one of many viable birth control options.

 *Greenwood, Jeremy and Nezih Guner (2009). “Social Change: The Sexual Revolution.” Population Studies Center PSC Working Paper Series University of Pennsylvania.

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In truth, so much of what happens to us in life is random – we are pawns at the mercy of Lady Luck. To take ownership of our experiences and exert a feeling of control over our future, we tell stories about ourselves that weave meaning and continuity into our personal identity.

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Yale scientists restore brain function to 32 clinically dead pigs

Researchers hope the technology will further our understanding of the brain, but lawmakers may not be ready for the ethical challenges.

Still from John Stephenson's 1999 rendition of Animal Farm.
Surprising Science
  • Researchers at the Yale School of Medicine successfully restored some functions to pig brains that had been dead for hours.
  • They hope the technology will advance our understanding of the brain, potentially developing new treatments for debilitating diseases and disorders.
  • The research raises many ethical questions and puts to the test our current understanding of death.

The image of an undead brain coming back to live again is the stuff of science fiction. Not just any science fiction, specifically B-grade sci fi. What instantly springs to mind is the black-and-white horrors of films like Fiend Without a Face. Bad acting. Plastic monstrosities. Visible strings. And a spinal cord that, for some reason, is also a tentacle?

But like any good science fiction, it's only a matter of time before some manner of it seeps into our reality. This week's Nature published the findings of researchers who managed to restore function to pigs' brains that were clinically dead. At least, what we once thought of as dead.

What's dead may never die, it seems

The researchers did not hail from House Greyjoy — "What is dead may never die" — but came largely from the Yale School of Medicine. They connected 32 pig brains to a system called BrainEx. BrainEx is an artificial perfusion system — that is, a system that takes over the functions normally regulated by the organ. The pigs had been killed four hours earlier at a U.S. Department of Agriculture slaughterhouse; their brains completely removed from the skulls.

BrainEx pumped an experiment solution into the brain that essentially mimic blood flow. It brought oxygen and nutrients to the tissues, giving brain cells the resources to begin many normal functions. The cells began consuming and metabolizing sugars. The brains' immune systems kicked in. Neuron samples could carry an electrical signal. Some brain cells even responded to drugs.

The researchers have managed to keep some brains alive for up to 36 hours, and currently do not know if BrainEx can have sustained the brains longer. "It is conceivable we are just preventing the inevitable, and the brain won't be able to recover," said Nenad Sestan, Yale neuroscientist and the lead researcher.

As a control, other brains received either a fake solution or no solution at all. None revived brain activity and deteriorated as normal.

The researchers hope the technology can enhance our ability to study the brain and its cellular functions. One of the main avenues of such studies would be brain disorders and diseases. This could point the way to developing new of treatments for the likes of brain injuries, Alzheimer's, Huntington's, and neurodegenerative conditions.

"This is an extraordinary and very promising breakthrough for neuroscience. It immediately offers a much better model for studying the human brain, which is extraordinarily important, given the vast amount of human suffering from diseases of the mind [and] brain," Nita Farahany, the bioethicists at the Duke University School of Law who wrote the study's commentary, told National Geographic.

An ethical gray matter

Before anyone gets an Island of Dr. Moreau vibe, it's worth noting that the brains did not approach neural activity anywhere near consciousness.

The BrainEx solution contained chemicals that prevented neurons from firing. To be extra cautious, the researchers also monitored the brains for any such activity and were prepared to administer an anesthetic should they have seen signs of consciousness.

Even so, the research signals a massive debate to come regarding medical ethics and our definition of death.

Most countries define death, clinically speaking, as the irreversible loss of brain or circulatory function. This definition was already at odds with some folk- and value-centric understandings, but where do we go if it becomes possible to reverse clinical death with artificial perfusion?

"This is wild," Jonathan Moreno, a bioethicist at the University of Pennsylvania, told the New York Times. "If ever there was an issue that merited big public deliberation on the ethics of science and medicine, this is one."

One possible consequence involves organ donations. Some European countries require emergency responders to use a process that preserves organs when they cannot resuscitate a person. They continue to pump blood throughout the body, but use a "thoracic aortic occlusion balloon" to prevent that blood from reaching the brain.

The system is already controversial because it raises concerns about what caused the patient's death. But what happens when brain death becomes readily reversible? Stuart Younger, a bioethicist at Case Western Reserve University, told Nature that if BrainEx were to become widely available, it could shrink the pool of eligible donors.

"There's a potential conflict here between the interests of potential donors — who might not even be donors — and people who are waiting for organs," he said.

It will be a while before such experiments go anywhere near human subjects. A more immediate ethical question relates to how such experiments harm animal subjects.

Ethical review boards evaluate research protocols and can reject any that causes undue pain, suffering, or distress. Since dead animals feel no pain, suffer no trauma, they are typically approved as subjects. But how do such boards make a judgement regarding the suffering of a "cellularly active" brain? The distress of a partially alive brain?

The dilemma is unprecedented.

Setting new boundaries

Another science fiction story that comes to mind when discussing this story is, of course, Frankenstein. As Farahany told National Geographic: "It is definitely has [sic] a good science-fiction element to it, and it is restoring cellular function where we previously thought impossible. But to have Frankenstein, you need some degree of consciousness, some 'there' there. [The researchers] did not recover any form of consciousness in this study, and it is still unclear if we ever could. But we are one step closer to that possibility."

She's right. The researchers undertook their research for the betterment of humanity, and we may one day reap some unimaginable medical benefits from it. The ethical questions, however, remain as unsettling as the stories they remind us of.

Ashes of cat named Pikachu to be launched into space

A space memorial company plans to launch the ashes of "Pikachu," a well-loved Tabby, into space.

GoFundMe/Steve Munt
Culture & Religion
  • Steve Munt, Pikachu's owner, created a GoFundMe page to raise money for the mission.
  • If all goes according to plan, Pikachu will be the second cat to enter space, the first being a French feline named Felicette.
  • It might seem frivolous, but the cat-lovers commenting on Munt's GoFundMe page would likely disagree.
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