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570004 tn?1226983796

menstrual cycle shortening

Over the past several months (since about July – a month or two after I started on levothyroxine) I've noticed that my menstrual cycle is about a week shorter than it used to be.  It was about 36 days before, but now it seems to be about 28 days at most - if anything it's getting shorter; not going back to the way it was before.  Does anyone know if this is normal / related to hypothyroidism?  I am 31 years old.

Thank you.
8 Responses
Avatar universal
Funny you should mention this. I am dealing with cycle problems as well. Mine started in Dec.; I had a cycle on Dec. 3, (3-4 days) Dec 22 (3-4 days) and Jan 6 (still on it, day 11). This is not normal for me....

My dr. thinks it is due to thyroid dosage change or menopaus, but I am not so sure. I am 38 though. But I have always had thyroid dosage changes, and this has never happened, yes my ovaries hurt. I did make an appt. with gyno dr, but not until Feb. I did call my PCP about still on the 3rd cycle all she said is that it will eventually end. Needless to say, I was not happy with that answer....
570004 tn?1226983796
day 11!  You must not be so happy!

I am unsure whether I should say anything about this to my doctor; it's not really a problem for me, other than being kind of annoying...
393685 tn?1425816122
I am 43 and going through alot of cycle changes too. It does have alot with balancing  thyroid hormone - but it does go a bit deeper than just that too.

Facing hypothyroidism your body is adjusting to changes going on in the system - other things are changing too - some good some bad. Perimenopause is very common naturally to start in mild forms in a woman reaching past her 40's and lingering for years before it becomes full blown.

When hypothyroid - the process becomes sooner for some. Finding a doctor who can deliver results of a hormone panel and work with you can be a different story. Most doctors will say you are in normal ranges on your FSH - estrogen - progesterone and Testasterone levels but in fact you might be off a hair or more on ONE specific hormone throwing you cycles off and mocking symptoms of hypothyroidism entirely.

I don't know what advice you can get - except finding a doctor who looks directly at the symptoms and works with you to balance out. I was fortunate enough to find a doctor that does this and found I was estrogen dominant. My levels of progesterone were low and my female hormones were not working to keep me healthy - along with remaining hypothyroid for so long and was left very ill.

Getting on progesterone was not as easy as "Just that" either. After I began the Rx cream I started having adult acne break outs and my periods were coming closer together and very heavy. I was calmer inside and not so anxious - but I looked like a zit factory.

I am still working on a bio identical hormone balance that is completely right for me. This can be another long process - just like thyroid and adrenals were.

Avatar universal
I just started on synthroid in April and have had very irregular and shorter cycles since then. One month my cycle is 25 days, the next it's 29 days. I used to never have a cycle of less than 28 days. It's rather disturbing since I'm trying to get pregnant after 2 miscarriages. Have you had any luck finding out more info about your changing cycle and the relation to hypothyroidism? Incidentally, I'm almost 38.
219241 tn?1413541365
Since I went hypo earlier this year, I have noticed that my period cycle is a week earlier each time now too. Used to be on the knocker of a particular day, could almost even tell you the time it would arrive! Now it is almost exactly 3 weeks to the day each one starts. So makes getting PMS a really big drag.
When I was Hypo years ago the very same thing happened. I was not on any medication for thyroid back then, so seeing the same thing happening now and being on meds, I can say it isn't the medication, but rather, the hypo state.
Avatar universal
maybe I should mention that I went through early menopause and finished it at 46 years of age...although I was diagnosed at the start of it at the age of 36.
I went for testing last year and my Doc told me I had finished the menopause 3 years prior !
So basically I was going through it while having Graves Disease and never connected the two.

My menstrual cycle was irregular to start with ...sometimes 2 a month, then sometimes none for 3 months then after 2 years I went 11 months without a cycle.
Then finally 12 months without a cycle.
It has been 3 years now since I last had a menstrual cycle and blood tests confirmed I was Post Menopausal.

Graves and Hashis are well known for interfering with womens cycles and early menopause.
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