The rapid reduction of progesterone in the last seven days of a woman's menstrual cycle can cause PMS symptoms.

“they're experiencing profound fluctuations in their hormones and this is another one of my favorite whiteboard topics and you know I remember there's this one patient I'll never forget she was I was a member sitting down with her in her living room actually drawing this out for her and explaining to her why she has PMS because her chief complaint actually which I thought was an odd reason to come to see me because I don't think like I offer any genius expertise on this but I mean mostly it was just to help control her her emotional swings during her sight and when I actually drew for her the time course of here the you know here's day one the day your period starts here's day one of your next cycle here's how your FSH your follicle stimulating hormone your LH or luteinizing hormone your estradiol your progesterone and your testosterone vary throughout that and let's highlight what's happening on about day 22 to 28 which is when you have this drop in progesterone and explaining to her that for some women that central meaning in the in the brain that reduction that withdrawal of progesterone can create emotional lability and other things”

“let's highlight what's happening on about day 22 to 28 which is when you have this drop in progesterone and explaining to her that for some women that central meaning in the in the brain that reduction that withdrawal of progesterone can create emotional lability and other things”

“it's that last seven days of that cycle that in a susceptible woman is what creates those PMS symptoms so it's the actually this is something that you would probably have a better understanding of than me there is something about this in a susceptible woman where the enormous reduction of progesterone so quickly is probably impacting something in her brain so I think this is a this is a legitimate thing right I mean you know it's not like oh she's crazy because she's having all these PMS symptoms know we know that that's the case because if you put women on progesterone for those seven days those symptoms go away so if you can stabilize their progesterone during the last half of their ludial phase and sometimes we would just do it for the entire luteal phase just put them on a low dose of progesterone all PMS symptoms vanish”

“for many women what's happening between between day 21 and day 28 is really profound physiologically so I you know we talk about this thing called PMs and I think any woman who's experienced it knows it's a real thing”