Quote from: Deborah on October 24, 2015, 08:50:41 AM
I'm just wondering if you might have an answer. At what stage in a pregnancy back in the late 50s or early 60s would a Dr have normally prescribed DES. Would it have been right at the start or sometime later? And at what point would right at the start be? My guess is that it's probably no earlier than at least four to six weeks after conception. A delay in administration of DES would answer the question of why so many are transsexed in the brain but exhibit no explicitly visible intersex conditions.
There's a table of doses taken from the 1953 Physician's Desk Reference here:
http://ireport.cnn.com/docs/DOC-1071366(the PDR is the industry "bible" that tells doctors how to prescribe a particular medication)
Apparently, that same table was published in the PDR every year until 1962, when it was replaced by a less specific recommendation to use doses of 25 - 100mg per day (even after that, most doctors probably stuck to what was in that table, since it was what they were already familiar with).
I put that table into Excel to see what the cumulative dose over the course of a pregnancy would be, and here's the results:

So, a total of 11,718 mg of DES over the course of a pregnancy if the dosing schedule was followed to the letter (which it probably was in a lot of cases, since it was the manufacturer's recommendation, and the patient would potentially have grounds to sue any doctor varying from it).
When you consider that a dose of between 1 and 3 mg per day will achieve suppression of testosterone production to castrate levels in an adult man being treated for prostate cancer, you can see how large these doses were, and how it's virtually inevitable that a male fetus exposed to this treatment would no longer be producing any testosterone during the second half of the pregnancy (which appears to be when all the important differences between male and female brains arise).
Note that the starting point was 7 weeks after the final day of the last period, which doesn't necessarily correspond to when conception actually occurred (it could be anywhere from that day up to a month later). For that reason alone, there'd be a fair bit of variability over how heavy exposure actually was during the critical period for genital development (between 7 and 12 weeks after conception), which probably explains the wide range of variability in effects on the genitals (anything from relatively normal looking male genitals to something that looks like high grade AIS). There wasn't nearly as much variability during the critical period for brain development though; it was uniformly high. It makes me think there must still be quite a lot of people who are trans as a result of DES but have yet to come out, either because they're in denial about it or are remaining closeted for personal reasons.