One of the biggest ongoing studies in the developing-world Obstetrics is the Calcium and Pre-Eclampsia (CAP) Trial. The hypothesis is that calcium supplements prevent the development of Gestational Proteinuric Hypertension – but if you like history, where this idea originated is a wholly fascinating story.
The 1970s was a turbulent time in Argentina, which was experiencing a military dictatorship and a lot of oppression. At this time, anybody considered to be a remote threat was eliminated; including many talented young people who could be considered ideological threats. (I am not well-versed in Latin-American history, but reading up about this “Dirty War” is interesting and horrifying.)
One young OBGYN in Argentina feared for his own life after his brother and sister-in-law – similarly well-educated – disappeared. Nobody knew where these thousands of young people were disappearing to, but years later it was revealed that many of them were loaded in airplanes and then dropped out into the ocean.
The OBGYN in question was José M. Belizán, today well-known in the world of maternal health, and he fled to Guatemala in the name of self-preservation.
When he started working in Guatemala he noticed something particular: the incidence of pre-eclampsia in Guatemala was much lower than in his native Argentina.
Both Latin-American countries, the reason for this discrepancy was not blatant.
Belizan noticed that although the diets of both nations have corn as staples, Native Guatemalans soaked their corn in lime water before cooking. As a result, the major difference between their diets were that Guatemalans ingested substantially more calcium than Argentinians.
Since then, numerous studies have proven the efficiency of Calcium supplementation in reducing pre-eclampsia and pregnancy-induced hypertension in high-risk women. Some studies have failed to show the association, thus not all clinicians are comfortable with it, but in South Africa and Argentina, high-risk women are given Calcium and the CAP Trial is ongoing.
I am privileged that I am currently training under one of the professors instrumental in this trial, but what I like most about this story is the history. It is not pure medicine and biology and chemistry: it is history and war and tragedy that all form part of this story, and it reminds me that no matter how isolated and pure our field tries to be, it really is part of the bigger picture.
1. The relationship between calcium intake and edema-, proteinuria-, and hypertension-gestosis: an hypothesis by J.M. Belizan and J. Villar, The American Journal of Clinical Nutrition (the original study, free full text here)
2. Calcium supplementation to prevent pre-eclampsia — a systematic review by Hofmeyr, Roodt, Atallah and Duley, South African Journal of Obstetrics and Gynaecology (free full text here)
3. WHO Recommendations for Prevention and Treatment of Pre-Eclampsia and Eclampsia (free, full text here)