Welcome to the final installment of our series chronicling the history of the birth control pill. In earlier installments, we learned how chemists were able to extract a chemical from a wild yam called barbasco and convert it into progesterone, the active ingredient in the Pill.

In 1960, the FDA approved oral contraceptives for marketing. At this time, more than 2 million Americans were already using the Pill — and more than 100,000 Mexican campesinos (a Spanish word for peasants) were harvesting barbasco, the wild yam necessary for its production. By 1974, 125,000 Mexicans were collecting and selling barbasco. Every week, during the barbasco trade’s peak, an excess of 10 tons of the plant were removed from tropical Mexico.

Though they were paid subsistence-level wages for their labors (half a peso per kilo of dried root), and the work itself was dangerous and backbreaking, they were putting Mexico on the map in the scientific community. After establishing a hormone synthesis industry in Mexico, the European stranglehold on hormones was loosened and the price of progesterone plummeted from $80 per gram to less than a dollar per gram. By 1954, Syntex, a Mexican laboratory, was the largest producer of steroids in the world, having usurped Europe’s monopoly.

Scientists depended on the campesinos’ knowledge of soil conditions and growth cycles, as well as their ability to differentiate between different species of yams. The campesinos relied on their knowledge of weather patterns, differences in root coloration, and size variations to determine when they could dig up roots with the highest concentrations of sapogenin, the chemical that was converted into progesterone in the laboratory. Over the decades, the campesinos slowly gained an education in organic chemistry. Continue reading →