Sometimes an intriguing new theory arises that drives scientific thinking into a whole new line of research. I believe such a theory has now arisen regarding pregnancy.

It will influence the future of medical practice and drug development.

In science, paradigm shifts happen when a collection of “repeatable anomalies” persuades enough scientists that the old theory isn’t complete.

Eventually, someone comes up with a new theory that explains these mysterious observations. (It also explains the non-anomalous data just as well as did the old theory; else it would be rejected.)

Most of the time, such new theories go through a long period of incubation, both in the development and in the acceptance. There is often fierce and even emotional disagreement about which theory is better.

Sometimes, the new theory sails through with little opposition. That’s rare, and in my view only happens when it doesn’t threaten entrenched interests. (While scientists try to be objective, they have research budgets to protect and reputations based on their published papers to preserve.)

The New York Times reports that pregnancy may be viewed, in part, as a battle for nutrients. From one perspective, this shouldn’t be surprising. After all, for much of humanity’s history people have fought the environment and each other to avert starvation.

However, we’ve long harbored the presumption that a mother’s top priority is the care of her unborn child. Isn’t it?

While no one is suggesting that mothers don’t go through arduous and even heroic efforts to provide the best for their fetuses, it’s also a fact that most mothers have multiple children. Also, they often intend to produce more children after the present womb-dweller.

This creates the possibility of competition for scarce resources. From the infant’s point of view, it wants and demands all that will help it to grow and be healthy.

The mother’s view is more complicated. While she keenly desires her child’s welfare, she also has great concerns for her other children. (Note: Abortion is not yet discussed as part of the new theory, but may come to be added later.)

The mother must balance competing interests. And here we see the potential for conflict between her and the developing infant.

Half a million women die annually during pregnancy or childbirth. Millions more suffer serious injuries. It’s no cakewalk.

Dr. David Haig has a new theory that’s rapidly winning acceptance among various stripes of scientists in medicine and biology. It holds that pregnancy is an ongoing battle between mother and fetus about nutrition.

Dr. Haig teaches evolutionary biology at Harvard. A basic question long nagged at him:

“Pregnancy is absolutely central to reproduction, and yet pregnancy doesn’t seem to work very well,” he said. “If you think about the heart or the kidney, they’re wonderful bits of engineering that work day in and day out for years and years. But pregnancy is associated with all sorts of medical problems. What’s the difference?”

The difference, he argues, is that only pregnancy involves two individuals. In his view, this explains a lot that’s heretofore remained mysterious.

For instance, in fetuses the copies of some genes are shut down, depending on which parent they come from.

The placenta isn’t a passive instrument. Instead, it grows blood vessels that search out penetrate the mother’s tissues in search of nutrients.

Dr. Haig points out that while we’ve long viewed mother and fetus as a cooperative system, this is only partly true. They do have different genes, and in every other instance that’s been studied different organisms compete at least some of the time.

So why not here?

Back in 1993, Dr. Haig predicted that this would serve to explain many of the health-related problems of pregnancy. (While the focus of his research seems to be on the mother’s health, clearly he would agree that this might also explain phenomena such as spontaneous abortion.)

Pre-eclampsia is a major mystery explained by Dr. Haig’s theory. In the later stages of more than 5% of pregnancies, the woman’s blood pressure reaches dangerous levels.

Haig’s view is that this happens because fetuses cause it. (They do so through an as-yet unknown mechanism, itself a future research topic.)  Raising mother’s blood pressure causes more blood to enter the placenta, giving the baby more nutrients.

The Haig theory states that this happens in all pregnancies. This creates a testable hypothesis: Are there micro-increases in blood pressure during all pregnancies?

Meanwhile, other researchers have confirmed that women with pre-eclampsia show high levels of a protein called “sFlt1″ in their blood. Interestingly, the protein prevents her body from quickly repairing minor damage to her blood vessels.

That minor damage raises blood pressure, and it’s the late-stage fetus that produces this sFlt1, not the mother. I marvel at the subtlety of this. While major damage would be dangerous to both mother and child, such minor damage isn’t. It helps feed the baby, at slight expense to the mother.

There’s also a process called genetic imprinting that the Haig theory explains. Genes come in pairs, one from each parent. Normally, both genes in such a pair respond the same way.

However, dozens of genes have now been identified where one parent’s genes remains silent. It doesn’t make proteins. Many of these genes either accelerate or slow the growth of the fetus. It now appears that the mother’s body turns these on and off to match her nutritional resources.

Some such genes even do this dance after birth, when the mother’s production of milk may conflict with the infant’s demands for it. This is especially true when there are multiple babies.

The influence of this research may extend far beyond pregnancy. For instance, it now appears that genetic competition between baby and mother influences and perhaps in some cases triggers psychological disorders like depression and autism.

What’s the significance of this for medical research and drug development? I believe it will open the doors to a whole new class of drugs. These drugs will be designed to reduce the risks pregnancy brings to a mother while in no way damaging the fetus.

It’s a tightrope act, one where the famous law of unintended consequences may be especially active. If I were making medical policy or running research at pharmaceutical companies, I’d tread very lightly on this one.

But I’m not, and where there’s a buck to be made the drug industry surely follows. I’ll keep my fingers crossed and hope that this emerging line of research follows the Hippocratic dictum of “first, do no harm.”

I’ll also be watching to see which bright medical researchers come up with the first drugs.

To your profitable future,
Jonathan Kolber
April 4, 2007

P.S.: Get ready for the worst property-led recession of the last 76 years. Nobody’s money is safe. The “second wave” housing tsunami of 2007-2011 is about to hit, and smart investors are already battening down the hatches.

Penny Sleuth Contributor

The Penny Sleuth also features commentary by other financial analysts, small-cap experts, investment gurus and an array of contributors from various fields and occupations. Their diverse insights and contrarian investing ideas are hand selected by the Penny Sleuth editors.

View articles by Penny Sleuth Contributor