Except that’s not what you said in the OP, Jim. You said:
The bit you quoted does not specify Lesbianism. Also note it says “some support for this hypothesis.” It’s an hypothesis.
Even if you had gotten it right, an outdated manual is not persuasive. To illustrate, go back to the original 1899 Merck Manual and find recommendations for [DON’T TRY THESE AT HOME, KIDS]:
• cocaine for angina AND alcoholism
• arsenic for anemia
• laxatives for chicken pox
• strychnine for constipation
• chloroform for hiccups
• cold douches for insomnia
Your first thought upon finding that old passage should have been, “Gee, more studies have probably been done in 30 years. I wonder if a more up-to-date edition of Merck’s says anything about this.”
No, Jim. Look at my post again. The point is that an outdated medical manual is no use in an attempt at persuasive argument (or in an attempt to treat a condition). An 1899 manual makes this especially obvious, so it was a good illustration of that principle. No comparisons made.
Merck Index 13th Edition (2001), which is in my stack o’ outdated medical texts to get rid of, has no citations related to sexuality and DES under the diethylstilbestrol entry.
OTOH, 30 year old studies about a medication that was withdrawn for use in pregnancy 50 years ago should be evaluated on their merits, not rejected out of hand.
Having said that, if exogenous hormones had an effect on orientation, I’d expect it to decrease incidence of lesbianism.
? You’re comparing a 29 year difference in science to a 122 year one