Sudden Cycle Changes- vitamins? normal?

[lineska]

You ladies seem to be pretty knowledgeable, so hoping someone might be able to tell me if I'm going crazy...

I've always been good about tracking my cycle and it's always been fairly regular, but long--right around 40 days. I started taking prenatal vitamins a few weeks ago as I've just started TTC and I got my period on Day 26.

I have never had a 20-something day cycle in my life. At first I thought it was ovulation spotting, but it's definitely a normal one. I know cycles can vary, but by this much? I'm 14 days early!

I've been wracking my brain, nothing else has changed that I can think of. Is it even possible that I was lacking in something before (B vitamins? Folic acid?) that contributed to long cycles? Has anyone else had their cycle just randomly change like that and did you ever figure out why?

(I have an ob-gyn appointment coming up soon anyway, just wondering if anyone might have an explanation! Googling has failed me so far.)

[southern.maple]

Is it even possible that I was lacking in something before (B vitamins? Folic acid?) that contributed to long cycles? Has anyone else had their cycle just randomly change like that and did you ever figure out why?

Yes, that is very possible. Changes in diet and exercise can easily affect your cycle. Definitely bring it up with your OB/GYN, though.

My change was not as drastic, but for a long time my cycles were about 35 days. I started exercising regularly and taking iodine supplements for my hypothyroidism, and suddenly my cycles were 28 days. Over time they've evened out to 32 days.

[kibby]

Last month my cycle was about 5 days early, I thought it was a lucky break as it was otherwise due to show up on my poolside vacation, but this month it has shown up 12 days early! Very odd for me! I can usually time down to the day! Before my IUD it was down to the hour! I also have a ob/gyn appt soon, so I plan to ask as well! So confusing!