You can take weeks, 2,3,4
Note that progesterone is the substrate for production of cortisol. Low progesterone might undermine that. Progesterone is made in the ovaries [and testes], as well as the adrenals. Progesterone is very important for brain function and recovery from trauma. So is vitamin D-3. Studies show that progesterone+Vit_D3 is greater than the sum of the parts. The root of this understanding that women survive and recover better than men from brain injury. Unfortunate, there is not much known, that I have found, about whatever would be optimal for males. For cycling females, their levels are all over the map and there are no simple answers there.
Everyone is different in terms of how well they absorb, how fast they metabolize and how much they need. So you will be on your own and labs can be helpful. Apply 1/2 teaspoon to one forearm and then wipe arm against arm all along inner arms. You can apply to breasts and see if that improves any issues with breast tenderness. You can also apply to belly or inner thighs.
There are signs to go by. Progesterone can reduce or eliminate breast tenderness [a sure sign of estrogen dominance], PMS, painful periods etc.
Estrogen dominance also can contribute or cause endothelial dysfunction, the root cause of arterial disease. Also causes enlargement of the uterus and fibroids. I have seen cases, women I have worked with, where progesterone has normalized the side of the uterus and in one case, fibroids shrunk then were spontaneously expelled. In that case, an otherwise vibrant woman in her 30’s had her doctors telling her that she had to have a hysterectomy. Also a case where a women heading into menopause had her cycle start back up. She tried a different brand [not KAL], and started to hot flash. So there is a big issue about how well a cream is absorbed.
Speaking of absorption: We know that most, seems like all, men who have hypothyroid problems, typically subclinical, cannot absorb testosterone creams or gels. This inability to absorb transdermal testosterone might translate into women not absorbing progesterone transdermally. So you can watch for that on labs. We really do not have enough data to know one way or another if effective thyroid meds can reverse this. Note that progesterone and pregnenolone have very poor oral bio-availability. 100mg/day capsules can be ineffective. This is one of the reasons that progesterone like chemicals, progestins, have been created. This also creates a situation where a novel drug can be created and patented, then development and drug trials are expensive. Doctors have been told that these drugs do the same thing as progesterone. True to some extent, and fatally wrong in other ways. Progestins seem to protect breast tissue from estrogens, but not endothelial tissue. That is why the womens health initiative showed increased deaths from heart attacks. When the shit hit the fan, the drug industry blamed HRT [false] and deflected the blame, and the press obediently spread the lies. None of that should have been a surprise. There have been warnings about such things for Oral Birth Control [OBS] since the 1960’s. All steroid hormones are transported to the cell nuclei where they affect the gene expression of your DNA. Throw synthetic chemicals in there and the results can be unexpected. Steroid hormones can increase gene expression, or reduce gene expression. And any one steroid hormone can have multiple effects for multiple genes. We simply do not understand that much about what is happening. So we have highly effective and absorbable progestins, that can cause heart attacks, strokes, blood clots etc. There is no way to predict which women will have such events and which will not. But there probably is an increased problem with arterial problems with all women, that is hidden inside the effects of aging.
Thyroid meds: You body temperature can be a good guide to your thyroid hormone status. If you can’t get to 98.6 mid afternoon, you are under-medicated. Use an oral thermometer when you have not been eating, drinking, talking, working out…
Any iodine in your diet from vitamins or iodized salt? Iodine is stored in breast tissue and there is data suggesting that low iodine increases breast cancer risks. Why is iodine there? Prime reason may be to provide iodine to babies. Because of this, women store more iodine than males. Most iodine is stored in the thyroid gland. Adults can store 1.0-1.5 GRAMS of iodine. When taking thyroid meds and if TSH is repressed, what are the issues with iodine in the thyroid gland? I do not think that this is understood. There are other roles for iodine in the body other than the thyroid. However, these are not understood.
If total cholesterol gets below 180, you have a problem, starts to be a concern at 160. Low cholesterol undermines steroid hormone production. Monitor DHEA-S.
Focus on the cell wall permeability, nutrients that I suggested. There is good info at LEF.org