Clomid half-life

I’ve been researching Clomid today and found this:
“With a half-life of 5-7 days, it is possible that clomid, after inducing a successfully fertilized ovulation, remains in the mother’s system well into the initial weeks of pregnancy…The estrogen receptors necessary for interaction with clomid are not present until the fetal stage of pregnancy (56 days post-conception).”
So your body has 56 days to clean out the residual Clomid before it can begin to effect the baby. Clomid has a half-life of 5-7 days so every 5-7 days the amount in your system is reduced by 50%. Using 6 days as an average, I figured the following:
Day Clomid taken: 100%
6 days later (approx ovulation time): 50%
12 days later (baby approx 6 days): 25%
18 days later (baby 12 days): 12.5%
24 days later (baby 18 days): 6.25%
30 days later (baby 24 days): 3.125%
36 days later (baby 30 days): 1.562%
42 days later (baby 36 days): 0.781%
48 days later (baby 42 days): 0.390%
54 days later (baby 48 days): 0.195%
60 days later (baby 54 days): 0.097%
So less than 1/10th of a percent is still in your body when the baby reaches 56 days post-conception. That’s not a whole lot- less than 1/20th of a mg per 50 mg taken- but more than I thought before I calculated it up. I take 150 mg for 5 days and that comes out to 1/3 of a mg still in my body (with the error of me assuming it’s all taken at once; it’s actually a smidge less) when the baby reaches fetal status.
Interesting. I guess that solves the riddle of why some non-ovulatory women go on to ovulate the month after stopping Clomid.