I am injecting estradiol valerate (EV) intramuscularly (IM) since about 3 years. At first, the injection was every 7 days but then, the interval was shortened to 5 days because of symptoms resembling PMS before day 7 (at that time though, whether PMS was actually occurring or not wasn't perfectly clear but I did it anyways). Lately, I noticed (but this could have happened much earlier and I just didn't pay attention) that I would get headaches from time to time but I remained clueless as to when they would occur during my cycle. Today, day 3 of my cycle and I noticed a headache slowly coming on at around noon. I decided to try something new and inject at around 7 pm today and try and figure out if the headache was due to a drop in E2 levels. 2 hours later, my headache was GONE! This is in agreement with a study which shows that E2 levels dramatically increase after only 1 hour, up to 18 times with IM EV.
Headaches is often used as a marker for determining when E2 levels drop too much. If I am right about this, this means that by day 3, my E2 levels drop too much and I need to inject again. Why this quick drop in levels, you might ask? I can think of two major reasons why:
1) progesterone intake: I take a high dose. The progesterone may accelerate the rate at which E2 drops since it is known to increase metabolism of E2 to E1. This may explain why I get headaches with progesterone and why these increase when I take more.
2) I am a stressed individual, in general (and due to circumstances), so this can accelerate the rate at which the estrogen is used up.
This could also account for why I got poor breast growth on IM EV as levels were dropping too fast (confirmed by lab tests, 2,500 to 1,300 pg/ml in just two days). Too much time was passing by as E2 levels were dropping.
I will continue injecting every 3 days or perhaps, just go by symptoms (i.e. headache). There may be times, perhaps, when I need to inject more frequently and then, other times, when I need to inject less often.
p.s.: my doctors allow me to decide on interval/injection frequency on my own, depending on symptoms as long as I keep monthly dose the same.