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Original poster

Anyone found levothyroxine affected periods?

30 replies

Terramirabilis · 28/08/2013 05:32

I was diagnosed as having a slightly underactive thyroid at the start of this month. I've been taking 50 mcg of levothyroxine since then. I'm now on day 41 of my cycle with no sign of AF. My cycle is generally 30-32 days. Has anyone who's been taking it for longer than me found it was disruptive to their cycle?

OP posts:
digerd · 28/08/2013 07:01

No. When I was overactive - too much Thyroxine produced by my Thyroid- my periods stopped altogether.
My SIS had a very underactive Thyroid after the birth of her 2nd DC and she had no peiods either.

I was put on 50 mcms of Thyroxine years later but was menopausal by then and periods had stopped 4 years earlier.

Could you be pregnant?

mumat39 · 28/08/2013 14:08

Hi there.

I was diagnosed with hypothyroidism when my Dd was about 3 months old. It is the permanent variety, unfortunately.

I have just checked the leaflet on my box of tablets and it states menstrual irregularities in the 'other side effects you could experience are' section.

Dd was my first and due to a goitre I was under the local hospitals care, and had to have regular scans. The doctor at the hospital was brilliant. It took a good few months to find the right dose for me, and once I had 'stabilised' in terms of my levels of TSH etc, he pronounced that I could now try for another baby. I fell pregnant with DS2 shortly after that.

So, I think it can affect your hormones in that way. You should be have your blood tested every six weeks I think to make sure the tablets are working. In your shoes I would go back to my Gp just o make sure it is just that, but also to have it noted on your records.

I hope it all settles down soon and that your af arrives soon.

Take care

mumat39 · 28/08/2013 14:10

Sorry, in the early days you should have your blood tested every 6 weeks, until your levels settle.

hellymelly · 28/08/2013 14:15

That is interesting, as my periods changed when i started thyroxine, 11 months ago. I had put it down to my age as I'm late 40's, but maybe it is the levothyroxine.

Original poster
Terramirabilis · 28/08/2013 17:39

Sorry digerd should have said that the reason for delayed AF can't be pregnancy. When I had a colposcopy last week I had a pregnancy test beforehand which was negative.

I am going back for a six week blood test in a couple of weeks so when I speak to the doctor about those results I'll ask about the missing AF. It is annoying because having just got the all clear from the colposcopy we are ready to ttc. Quite difficult though with a missing menstrual cycle!

OP posts:
digerd · 29/08/2013 06:09

Good luck with TTC.

Tapirbackrider · 29/08/2013 11:46

I've found it to be the other way around (just to be awkward).

My periods were all over the place before I started on the Levothyroxine, but are now very regular - just blardy heavy.

I'm on 125mcg btw.

Keeping my fingers crossed for you.

TwoStepsBeyond · 29/08/2013 12:09

Mine are a bit irregular but I'd never made the connection! Been on Thyroxine for 13 years and never read that particular side effect! Blush

Mine can be every 3 weeks or sometimes 7 weeks in between and sometimes ridiculously heavy. Thanks for the heads-up that it could be the pills (or I suppose the condition itself) causing irregularity.

Monkeys121 · 03/03/2019 21:57

I just started taking levothyroxine 100mg dose once a day just getting very heavy periods stomach cramps why is this normal

Mittens73 · 29/01/2020 03:25

I’m so confused and need advice. I just got over my period and since then when I wipe after I pee I still have blood. But nothing in the toilet. This happened to me a few years back and I bleeded for 6 months straight and had a lot of year done and was put on levothyroxine for my thyroid. Well it’s back again and I don’t know why. Has anyone gone through this

Bunnyfuller · 29/01/2020 20:19

When I was diagnosed with hypothyroidism and went on the meds, 2 months in I finally started having regular periods, for the first time ever.

MrsCowboyJack · 04/03/2020 02:23

My dr diagnosed me with a "slightly underactive" thyroid and prescribed 25 mcg of levothyroxine. This drug has done nothing but screw up my normally regular period. I have had no other thyroid symptoms at all, I only asked if they'd check it because it runs in my family and I am going to be having a tubal reversal on April 9. I have had nothing but horrible bleeding since taking it. I finally stopped taking it and I feel completely normal but my period is now on day 16!!! I have NEVER been irregular in my whole life until this drug! It's horrible!

Hadenoughofitall441 · 04/03/2020 22:56

I have congenital hypothyroidism, take Levo and have always been on the same cycle for 17 years since I started aged 14 there have been a few months where it’s been slightly off but that’s it.

Emmilija · 11/03/2020 22:43

I am on levo too, a few months ago. My cycle lasts 7 days and 7 more days I have dark brown discharge - when I pee and sometimes it is like coffee. My PAP test is ok, microbiological tests ok, ultrasound ok, hormones ok. It strated 2 years ago and I can't find the reason. Maybe is my underactive thyroid, maybe levo had worsen the situation.

Kjj30076 · 28/03/2020 11:32

Omg ! I started taking mine Jan 2020 inconsistently then in feb 2020 to now (every day consistently ) - since I’ve been on it regularly I haven’t had a period in feb and March (this month) I wiped and it was light and then the next day I wiped and it seemed like a good first day flow but this morning I wake up thinking TAMPON time and NOTHING not even a drop - I’m on 25mg - so you think My body is still regulating to the meds?? Before the meds I had a period every month on time like clock work now.....it’s like I’m
Begging AF to come

Kjj30076 · 28/03/2020 11:37

@MrsCowboyJack - omg omg omg yes!!! I agree
My mom has it so she said I should get my checked - it was slightly elevated the day I got it checked (even though months before that it was in normal range strange) so I was prescribed 25mg started regularly taking it feb 2020 (did NOT have a period) and then now March 28 2020 My period is here and not here lol SMH I’m 26yrs old and never had irregular periods BEFORE this pill

Jasmine91 · 06/05/2020 01:12

I’ve been taking 75 mcg of Levothyroxine for about 8 months now, had regular periods up to about 5 months ago, now my cycle ranges between 37 - 41 days. I’m sure it has affected my cycle and caused it to become irregular, but I continue to take it, as it is important to treat it.

Kats1988 · 06/09/2020 09:53

Hi, I think this has also happened to me. Took 25mg of Eltroxin for 28 days. AF delayed. Fairly worried. I had a slighted elevated TSH level GP prescribed Eltroxin.

Will my cycle return next month?

Logee43 · 24/12/2020 08:49

I started taking levothyroxine (low free t4) Nov 5th, two days before my cycle was to start. I am now on day 82. My pcp said to keep taking it and it should come back. I dont see gyno until jan 29th. I had regular 33 day cycles with 12 day luteal phases. Im at least glad to see im not the only one but this is hindering TTC as I have no signs of ovulation now either (temp, opk)

NJH8 · 31/01/2021 08:21

Just reading this thread after a morning on google! I was diagnosed with an underactive thyroid as I started trying for baby No2. Since taking thyroxine it my periods have been on time but for 3 days before really weird spotting, getting my hopes up for implantation bleeding! Anyone else experienced spotting before periods?

Toniiiii · 01/02/2021 19:25

Omg me too. My dose of thyroxine was doubled at the start of my cycle from 25mcg to 50. I usually ovulate on cd19 out of 32 day cycle. I'm now on cd24 and ovulation has still not happened. The only change has been the Levo dosage. What a nightmare!

emmskie03 · 06/02/2021 01:05

I was given thyroxine to deal with subclinical hypothyroidism when trying to conceive. I have PCOS and the thyroid levels were off and on when I had my first with clomid. Thyroid is one of the things they check.

I worked my way up to 75mg and my TSH stabilised around 1 but this took about 7 months. The next month I got pregnant!

LHX820 · 06/04/2021 02:06

I started 75 mcg of Levothyroxine March 3rd. I haven't gotten my period yet this month & am 6 days late. I've always had a normal cycle, no issues. I took two pregnacy tests - both negative. Called my endo & they said my thyroid disorder would cause irregular periods NOT the levothyroxine. I'm really frustrated

Monkeys121 · 06/04/2021 14:54

iwas on 100mg my periods went very heavy and regular

WarriorN · 06/04/2021 16:27

It can take a few months for your cycle to settle after reaching a good level of thyroxine; I wouldn't ttc till you know levels are right and you feel ok.

It's frustrating but ultimately you will be making better quality eggs and have more chance of conception l.

Make sure you're taking folic acid and vit d. A prenatal multi vitamin or a-z multivitamin with minerals can be a good idea simply as they include the right amount of iodine and selenium which is very supportive for your own and baby's thyroid health/ general development. (Never more than rda.)

(If on a full dose of thyroxine iodine is less important but still helpful.)