In a culture that promotes alternative medicine, natural childbirth, and sometimes-bizarre dietary supplements, it seems strange that natural infertility treatments are not well-known. A natural infertility treatment is not necessarily alternative medicine, but rather a conventional-medicine approach that seeks to cure the underlying cause of infertility, allowing natural conception. It stands in contrast to assisted reproductive technology such as in vitro fertilization (IVF), which is stick a "band-aid" solution that does nothing about the underlying causes of fertility problems.

Why is assisted reproductive technology the current standard of care for infertility? If you type "fertility treatment" into Wikipedia, you are redirected to "assisted reproductive technology." Wikipedia, being written collaboratively by people around the world, reflects the biases and attitudes of those people. Fertility drugs and IVF are what people think of when they think about infertility treatments.

I think the reason IVF is so popular — despite its astronomical cost and mediocre success rate (only 1 in 3 attempts results in a live birth) — is because it is a "magic pill" approach. It is a silver bullet, a straightforward process left in the hands of doctors. Natural fertility treatments are more complicated because they start with diagnostics, rather than jumping immediately into treatment.

Among the diagnostic steps used in natural fertility treatments for women are ultrasound, laparoscopy, and sonohysterosalpingography (SHSG) to look for structural problems in the reproductive organs, as well as hormone level checks. During her menstrual cycle, a woman's estrogen and progesterone levels can change significantly in as little as 24 hours, so daily or every-other-day tests are best. Any underlying disease or structural abnormality that is uncovered is treated to increase the odds of a naturally conceived pregnancy.

How successful is natural infertility treatment compared to assisted reproductive technology? IVF has a maximum success (pregnancy) rate well under 50% (for 27-year-old women), with an average success rate closer to 35%. Statistics for live birth are even worse, with an average of only about 27% of attempts resulting in live births. That means that an average of 8% of attempts result in a miscarriage or stillbirth (or, if the fetus is imperfect, abortion). The poor success rates reflect, in part, the fact that over 50% of embryos conceived in vitro have chromosomal abnormalities, as reported by Rebecca Taylor of Mary Meets Dolly. Natural fertility technology also has treatments for male infertility.

According to the Pope Paul VI institute, a major proponent of natural infertility treatment, so-called "natural reproductive technology" has higher success rates than IVF for various infertility diagnoses. These results are both statistically significant (i.e. not due to chance) and personally significant (i.e. they're a lot higher). For example, for a diagnosis of endometriosis, IVF has a success (pregnancy) rate of about 21%, while natural reproductive treatment has a success rate of about 57%. It reports a 37% success rate for tubal occlusion compared to IVF's 27%. The whopping 82% success rate reported for natural fertility treatment of anovulation (not producing mature eggs) may be due to straightforward treatment of the most obvious cause of anovulation, hormonal insufficiency (although I am speculating here).

I find it amazing that natural treatments for infertility are not better-known, even though they are more effective than current approaches. That's right: for infertile couples, it is more effective to try to conceive a baby the way nature always has than to inject a sperm into an egg under a microscope, with less chance of complications like chromosomal abnormalities and multiple gestation. Who wouldn't choose that first, if they knew it was available?

Image credit: "Test tube baby" by Brendan Dolan-Gavitt. (CC) Some rights reserved.

Above: Space shuttle Columbia lifting off at the beginning of STS-107, its 28th and final mission. Courtesy of NASA.

To NASA, it's STS-107. To most of the rest of the world, it was the Space Shuttle Columbia disaster of 2003. A briefcase-sized chunk of foam weighing a little over a pound hit the orbiter's wing at 800 feet per second — that's about 550 miles per hour — damaging the thermal protection system (TPS). The compromised TPS was not adequate to the 3000° F reentry temperatures, and on its landing approach, the shuttle broke up into a handful of fireballs over Texas and Louisiana.

The shuttle disaster happened on my birthday. It's the worst birthday I have ever had.

This catastrophic event recalled to mind the Challenger disaster of 1986, seventeen years and four days earlier. I was in elementary school, and they wheeled a TV into our classroom so we could watch the shuttle explode over the Atlantic Ocean.

Stephanie Barr is a NASA engineer who writes the blog Rocket Scientist. She was part of the STS-107 team, and has a blog post remembering the Columbia tragedy. Go over and read it right now. I'll wait.

Then come back and tell me where you were when the Challenger and Columbia disasters happened.

Elsewhere, this blog has noted efforts to generate petroleum using genetically engineered bacteria (Bell BioEnergy, Amyris and LS9). These methods use naturally-occurring abilities of certain bacteria to convert cellulose, a carbohydrate, to hydrocarbons, the chemicals that fuel our vehicles, heat our homes, and otherwise serve most of our energy needs.

Bacteria convert one type of chemical energy to another type, as explained here. Photosynthesizers such as green plants are needed to perform the first step of converting light energy into chemical energy for the bacteria to work on.

What if this middle step were eliminated? A new Bill Gates start-up, Sapphire Energy, begins and ends with the photosynthesizer — in their case, algae, single-celled plant-like organisms. The goal is to create "renewable gasoline," not ethanol, taking advantage of "non-arable land."

Another company, Solazyme, takes a more conservative approach, if anything about this field can be called conservative. It grows its oil-generating algae in the dark and feeds it sugar water, which must be derived from food sources. The fundamental principles are the same as with methods that use bacteria to produce renewable hydrocarbons.

Algae are aquatic organisms that require water to be circulated, a significant energy cost that currently keeps the price of algae-derived fuels high. This factor may limit algae's usefulness on an industrial scale. Algae also need a source of carbon dioxide. These fundamental differences may mean algae will turn out to be inferior to bacteria in the field of renewable fuels.

Or not. There are few certainties yet in this exciting, promising field. There is a lot of potential and a lot of hope, and I will be interested to see whether these new energy companies can bring down the costs enough to produce their products on a meaningful scale and compete with fossil fuels.

Read more at Scientific American.

I wrote a guest post on DNA computers over at the tech blog Live Crunch. DNA computers aren't computers programmed to interpret DNA. They are computers made of DNA. If that sounds intriguing, head on over for this bulletin style post. For more detail, see an overview, a short history, and an explanation of how it all works.

How does a biotechnology company like the ones described here make petroleum from plants? And what effect will all this new petroleum have on global warming?

All fossil fuels contain energy stored in the form of hydrocarbons. Different hydrocarbons have different uses. Methane, the simplest hydrocarbon, is the main component of natural gas, while various complex hydrocarbons make up petroleum. Gas and petroleum refiners process these hydrocarbons into an array of fuels like gasoline, diesel fuel, and jet fuel.

The hydrocarbon in fossil fuels began as a different type of molecule, carbohydrate. This carbohydrate was produced by plants, then converted by a geological process to hydrocarbon. So far, fossil fuels have been the only game in town for obtaining hydrocarbon. Renewable fuels currently in use, such as ethanol, belong to yet another chemical class and do not have the properties that make hydrocarbon so useful as a fuel source.

Producing renewable hydrocarbon begins with naturally occurring microbes called methanogens. (Technically, methanogens are not bacteria, although they are commonly described as such.) These microbes are found in many environments, including the guts of many animals, such as cattle and humans. Here they are notorious for the gas they produce as they feed on indigestible organic compounds.

These microbes convert one type of organic compound (carbohydrate) to another (hydrocarbon). The chemical pathways to do this are already in place, and through genetic engineering, biotechnologists aim to make organisms that produce different kinds of hydrocarbons which can be refined into fuel.

Plants are mostly made of a type of carbohydrate called cellulose, which is the favorite food of these microbes. This means that almost all plant products, including waste like straw, stover, and sawdust, can theoretically be converted into fuel.

Burning fossil fuels increases the amount of carbon dioxide in the atmosphere because the carbon was stored in the fuel, then released when the fuel is burned. Renewable hydrocarbons, on the other hand, have no net effect on atmospheric carbon dioxide. This is because the plants at the beginning of the cycle made their cellulose out of carbon they removed from the atmosphere. The carbon dioxide released when renewable hydrocarbons burn is equal to the amount that was previously removed by the plant sources. Therefore, these fuels not only have a practically limitless supply, they do not contribute directly to levels of atmospheric carbon dioxide thought to be involved in global warming. Their "carbon footprint" consists only of the carbon released by refining and transporting them. If these processes can be made to take their energy from renewables, the carbon footprint will theoretically be zero.

Bell BioEnergy was previously mentioned here as a start-up whose goal is to produce petroleum from agricultural waste using genetically engineered bacteria. This is a searingly hot technology field, and Bell BioEnergy has competitors: LS9, Inc. and Amyris Biotechnologies.

LS9 claims it will produce gasoline, diesel, and jet fuel from materials such as sugarcane and "cellulosic biomass" (such as sawdust and straw) by feeding them to a "proprietary microbe."¹ A population of this microbe ferments these into oil that can be refined into various types of fuels. About a year ago, LS9 estimated the timeframe to bring these products to market at three to five years.²

Amyris Biotechnologies states that its gasoline and diesel substitutes "will be made from the same feedstocks and production plants that are used to make ethanol."³ In the U.S., that feedstock is corn, while sugar from sugarcane or beets is most prominent in the rest of the world.⁴ Corn and sugar are not nearly as compelling as fuel sources as agricultural waste; nevertheless, the Amyris product will be fully renewable like the others.

The UK's Times Online claims that LS9 is one of "several companies in or near Silicon Valley" to enter the renewable petroleum business;⁵ it may be referring to Amyris, in Emeryville. Silicon Valley seems to be a curious place to find either an agricultural concern or an energy company, although the high technology involved in creating the microbes suits it just fine.

These Silicon Valley companies boast founders with impeccable academic pedigrees and impressive venture capital funding. Contrast that with Bell BioEnergy's roots hawking powdered peanut butter from a Georgia farm. The race to produce the first renewable petroleum-based fuels on an industrial scale promises lots of drama.

Notes

1. LS9, Inc. website.
2. Neil Savage, Technology Review. "Making Gasoline from Bacteria" (August 1, 2007). Massachusetts Institute of Technology.
3. Amyris Biotechnologies website.
4. James Jacobs, Ag Economist. "Ethanol from Sugar" (n.d.). United States Department of Agriculture.
5. Times Online."Scientists find bugs that eat waste and excrete petrol" (June 14, 2008).