Sitnews - Stories In The News - Ketchikan, Alaska - News, Features, Opinions...


Chemical Eye on Plan B
by Preston MacDougall


September 19, 2005

Latex is a water-based suspension of natural rubber. If properly tapped, it is secreted by Hevea brasiliensis, which is better known as the rubber tree. For sexually active college students, latex is also referred to as Plan A.

jpg Preston MacDougall

I am probably compounding my metaphors, but when two students are in love, latex is the "chemistry between them"and an unwanted pregnancy.

The natural rubber that is suspended in the milky latex is composed of very long (as far as molecules go) and stringy members of the terpene family. A monoterpene has two molecules of isoprene linked head to tail. Isoprene is a small hydrocarbon molecule with five carbon atoms, but only eight hydrogens. It is thus "unsaturated" and chemically active.

With slight chemical modifications that can occur after hooking up, such as adding an oxygen atom here or there, monoterpenes are surprisingly diverse. The myrcene in the oil of bay leaves is a kinky chain, the limonene in lemon oil has an annular structure, and camphor is a cagey little molecule that gives Vick's its vapor. There are many other mono- and sesquiterpenes found in the plant kingdom.

Larger terpenes can be found in plants and animals. For instance, the beta-carotene that is needed for love at first sight, is a tetraterpene (it contains eight isoprene units). The long molecules in the milky secretion of the rubber plant are made from thousands of isoprene molecules, all linked head to tail. After purification, and "curing" which involves cross-linking the chains, natural latex can be formed into commercial products such as surgical gloves and condoms (the common name for Plan A).

The sex hormones, that might have called Plan A into action, are also terpene-related - they are derived from triterpenes. This goes for both the androgens (his) and estrogens (hers). The hormones called progestins (also hers) are triterpene cousins as well, and they factor into Plan B.

Women who take birth-control pills digest a regimen of synthetic versions of both estrogen and progestin. This prevents the implantation of a fertilized egg in the uterus. However, if she is not on the pill, and he forgot to implement Plan A, then there is still a chance that Plan B could be put into action.

The trouble with that is Plan B currently requires a prescription. This can present a problem time-wise, since it is dubbed the "morning-after pill" for good reason, and prescriptions usually involve making appointments with very busy people.

Plan B, which is actually called Plan B, and is now sold by Barr Pharmaceuticals, contains essentially the same ingredients as "the pill." The dosage is much higher however, and this will reduce the chance of a pregnancy by a factor of ten, if taken within 72 hours of the failure of Plan A.

This is where the FDA comes in. Originally, back in March of 2002, a small firm called Women's Capital filed an application with the FDA to sell Plan B over the counter. Subsequently, studies were done by reviewers who are contracted to evaluate all new drugs and new uses of existing drugs. It is important to note that they are trained to do so using established scientific principles. During this same period, rights to the drug were purchased by Barr Pharmaceuticals.

Based on all of the studies conducted, the FDA advisory committee, in a vote of 23 to 4, recommended approval of the switch from prescription to over-the-counter in December of 2003. The political appointees at the FDA rejected the application in May of 2004, citing concern over the availability of the drug to young teens.

Following the advice given to it by the FDA, in July 2004 Barr resubmitted the application, but for availability restricted to women 16 years of age or older. After another year of delay, the FDA delayed its decision again. Finally, at the end of August of this year, when their own deadline for a decision had arrived, and with no scientific objections ever having been raised, Lester Crawford, President Bush's recently appointed FDA Commissioner, indefinitely postponed the decision.

Commissioner Crawford's excuse was that the agency needed to seek public comment, and that there were questions about selling the drug to women under 17 years of age. Derisive comments comparing the Commissioner's tactics to a game of Three-Card Monte were quick to come, as was the resignation of the director of the Office of Women's Health at the FDA. Susan Wood was quoted in Nature as saying "It was very unusual for the Commissioner of the FDA to overrule the recommendation of all of the professional staff."

Shortly after that, when the Director of FEMA was busy making excuses for lethally late rescue efforts in New Orleans, there were reports that certain heart defibrillators were short-circuiting, often at critical times, and that one college student in Minnesota had already died as a result. It was also reported that the FDA was aware of company-supplied data that had alarmed some cardiologists. When I read that the FDA had this data before it gave its approval, I started to wonder who might have been Dr. Crawford's roommate when he was in vet school (he is a Doctor of Veterinary Medicine). Were horse shows in the picture? Perhaps dog and pony shows.

If science and reason cannot be in the lead at the FDA, then I am afraid that a great number of co-ed couples, in addition to countless others from all walks of life, will needlessly go straight from the failure of Plan A, not to Plan C, but to latex gloves implementing "Plan D. & C."

Preston MacDougall is a chemistry professor at Middle Tennessee State University. His "Chemical Eye" commentaries are featured in the Arts and Public Affairs portion of the Nashville/Murfreesboro NPR station WMOT (


E-mail your news & photos to

Publish A Letter on SitNews
        Read Letters/Opinions
Submit A Letter to the Editor

Stories In The News
Ketchikan, Alaska