Did you know that antibiotics could affect the menstrual cycle? Indeed, most of them can have an effect on menstrual periods, with some reporting delays. Find out more about the connections between antibiotics and the menstrual cycle below.
Your Regular Cycle
During the first 14 days of a 28-day menstrual cycle, your follicle will start to grow and kick-start the initial production of additional estrogen. It will start to make the endometrium lining thicker. When ovulation commences, the estrogen hormone will be joined by the progesterone hormone from the corpus luteum to make the endometrium mature and thicker.
How Antibiotics Affect the Normal Cycle
Antibiotics can interfere with your body’s mechanism, which secretes the human chorionic gonadotrophin hormone (hCG) and cause uterus shedding to delay your period. This will happen mainly because the available estrogen will be reduced to cause a change in your cycle for it to become irregular.
A study done in 1947 shows that Penicillin caused heavier bleeding, changes in pain and PMS symptoms and the start of the cycle itself, but they stated that they weren’t able to find any correlative information regarding that.
There are actually two ways antibiotics could affect the estrogen metabolism. Most antibiotics are metabolized in the liver, and when they are present, the metabolism rate of estrogen as well as progesterone will be affected. This can interfere with the estrogen supply that is in the blood and causes an irregularity of the menstrual cycle.
In order for the follicular phase of menstruation to occur, the estrogen is needed to stimulate the ovaries and thicken the uterine wall. Without this, ovulation doesn’t happen or it happens late, which obviously affects when your period will arrive.
Other Issues with Antibiotics
There are some antibiotics that will cause diarrhea-like symptoms when they interfere with the stomach flora.
Even though it’s supposed to kill the bad bacteria in the body, it also affects and kills the good bacteria as well, which is why some women report yeast infections as well after their use of antibiotics.
The entero-hepatic circulation will be affected and cause a reduction of estrogen levels in the blood. It’s becausegut bacteria that usually re-activates small amount of estrogen in intestine are no longer available [1].
When the estrogen levels change in the blood, your cycle will be affected low estrogen levels fail to stimulate pituitary release of hormones. Your body actually ovulates based on the pituitary gland’s ability to identify that sufficient estrogen is in the blood, and then cause LH surge which causes ovulation on 14th day of cycle. So antibiotic treatment can affect these delicate hormonal balances.
So your body doesn’t have enough estrogen to regulate normal menstrual cycle.
Another important point to note is that antibiotics change your body’s metabolic performance and the ability to sustain a steady hormone level.
Use the Second Form of Protection if you are Not Trying to Get Pregnant
Antibiotics can also affect the estrogen as well as progestin levels in oral contraceptive pills. Estrogen is actually an active ingredient in these pills and the antibiotics will affect how it’s metabolized in the body.
Rifampicin and Rifabutin are liver enzyme-inducing drugs and can clear the estrogens from blood at faster rate thereby reducing the contraceptive benefit anticipated from contraceptive pills.
You should get medical advice if you are taking antibiotics in the first seven days of a new pill packet and you engage in sexual intercourse in the last five to seven days. The antibiotics could disrupt the normal protection that the pills provide and cause you to get pregnant.
So if you are taking antibiotics, ensure that you are also protecting yourself as well if you are not looking to have another child right now.
Reasons other than antibiotics that affect your period
While antibiotics get a bad rap regarding the effect on the body and the menstrual cycle, there can be other potential issues and situations that can go on with the body during the time frame. When sick, antibiotics or not, the body is being stressed to the max.
It is trying to accommodate for being sick and the stress of still having to maintain a home, a job, children, a spouse (because you know, moms don’t take sick days). So take into consideration that it can be affected by the meds or by stress, weight loss or gain, usage of birth control, and PCOS or thyroid conditions.
How to Prevent Antibiotic Related Period Issues
One way to help balance your hormones while you are on antibiotics could be to switch up your diet while you are taking antibiotics (and after as well if you are looking to maintain a healthy balance).
In order to balance the estrogen levels, you can add some fish oil, vitamin D, and vitamin B to your diet as well as probiotics, which can help balance that gut bacteria in a beneficial way.
Plus you’ll want to get enough sleep (which helps so many bodily systems) and be stress free (see above).
In general, antibiotics can affect so many bodily systems. Know that they shouldn’t be something that you take on a regular basis because it can cause antibiotic resistance in the body.
Take them only if necessary and ensure that you take the proper precautions for preventing pregnancy and keeping your other systems in balance.
If your period is still late, however, take a test and be confident with the results. But if you are still concerned with what is going on, be sure to talk to your doctor if you need more information on the effects of antibiotics and menstrual cycle.
References
- Estrogen-gut microbiome axis: Physiological and clinical implications. https://www.ncbi.nlm.nih.gov/pubmed/28778332
Hi..my last period was on 4 June …and now on 8 july I did not get periods..on 5 July I take test that was negative…I also took antibiotic for urine infection in June…now what should I do…I m worried ..plz reply thanks..
Hello Xyz, the taking of anti-biotics can definitely delay the period, so this might be what is happening.
My last period was on the 3rd of June.. i took antibiotics for 5 days… but my period not coming still now.. today is July 4th I am worried please give me some advice..
Hi there Sharmistha, the taking of antibiotics does delay the period. So no worries once you did not indulge in unprotected sex.
Comment Text*hey I was suppose to go on my periods on the 18 and I’m late with 12 days …and around 08 June I was having flu and tonsillitis the doctor gave me bren-400 ibuprofen pills and austell amoxicillin 500g for treatment could it be the reason why I’m late on periods …and since from the 18 my date for periods been having mild cramps everyday they come and go …what could be the delay please help????
Hello Kgomotos, yes this could very well be the reason why your period is delayed because of the taking of antibiotics.
In my pregnancy test there is no two dark line. When negative line is dark and positive dark line is very light. And in ultrasound there is no sac of pregnancy.. And I also used azithromycin.. Am I pregnant?
Hello Anikes, your comment is unclear, however if pregnant there should be an appearance of two lines, it doesn’t matter if the line is dark or light, two lines indicates a positive result on a pregnancy test.
Hello I used azithromycin antibiotic, is it affecting my period. I’m 10 days late. So I am worried. Please help me..
Hello Bhabana, the taking of anitbiotics delays a woman’s menstrual cycle.
Hi.. I have been on antibiotics for uti as well and yes my period delayed with over 2 weeks. I usually go 3 days on my periods then I am done, but its like 6 days now.. I am worried. Can I take something to stop them? Maybe Ibuprufen or contraception pill? I’m worried as they are painful this time around, which is unusual.
No Palesa, do not take anything to cease the natural flow of your periods, if this is very abnormal for you and is accompanied with terrible pain then see your doctor. However this might be as a result of increased stress, etc.
Hi…I was having the feeling of seeing my period so 2 days later I started seeing my period I inserted deeply a tissue paper to confirm and it was blood stained but later that night I took beecham ampiclox and by morning I was still having the feeling to see my period but it is not coming, neither is the tissue stained with blood again please help is it the ampiclox that caused it?
Hi there Alero, antibiotics delay a woman’s period, so this might be the reason why your period hasn’t started.
Hi i was using cifxime for a week and I am late for my period is it because of the anti-biotic
Hello Dawn, this might be as anti-biotics have a history of altering a woman’s cycle.
I started what I thought was my cycle the same day I started antibiotics for a uti. I only had a small amount of blood on Day one. Day two a spot of blood and brown discharge. Then nothing. Today nothing and I am 3 days past my period start date. Question is does it matter when you start taking antibiotics before it can affect your cycle? And can it cause your cycle to stop?
Hello there Rubiejayne, yes taking anti-biotics can alter a woman’s flow and cycle.
I took azithromycin. I am late for my periods, what should i do? Is this medicine the reason behind this or I should go for a pregnancy test?
Hello there Unknown, yes antibiotics are known to delay a woman’s cycle.
Hey There. My last period was on the 15th of may. I have irregular periods with 3 to 4 days early. Today is the 14th June and I am not seeing my period. I had unprotected sex in June 1st week[After 17 days of my period]. I was on some antibiotics for urinal infections in June after two days of having sex[used antibiotics on 20th day]. Is there any way I am pregnant? Very worried.
Hi there Unknown, anitbiotics are known to delay a woman’s cycle. However if you are worried about pregnancy please take a pregnancy test since you had unprotected sex.
Hi Mitch here, I am taking doxycycle for one week and I am worried today because my period comes every two week of the month but now it was delayed, should I need pregnancy test?
Hello Mitch, please take a pregnancy test to determine if you might be pregnant.
Hi
I went off the pill last year July and didn’t get my period for 5 months ..then January this year I got it for the first time again and then skipped a month after that I had two regular periods and then skipped May ..I’m not on anything at the moment and I didn’t take a pregnancy test because my periods havent been regular for a while ..Ive experience really bad pelvic pains last week and by my ovaries…today when I wiped there was this brown slimy discharge..could this be my period coming?
Hi there Mishe, yes this could be your period. However the only way to tell for sure is to wait around and see. All the best.
Good morning…please I am having a prolonged menstrual period, please what can I use to stop it? Thanks
Hello there Funmi, please see your doctor to figure out what is happening especially if this is something out of the norm for you. All the best.
Hi.. I had drips and I have been on medication which includes ibuprofen, D-Artepp and Fleming (amoxicillin 500mg + clavulanic acid 125mg) for weeks now treating typhoid and malaria.. I completed my drugs last week and I expected to have my period yesterday 21st of may but it didn’t come.. What could be wrong please?
Hello there Biim, anti-biotics (Amoxicillin) are known to change a woman’s cycle, your period should return soon but might be a bit delayed.
Thanks, A LOT Alison..
Milly. Please I am taking doxycycline and flagly and am on my period. Hope it won’t effect my period.
Hi there Milly, certain medications are known to alter a woman’s cycle, you can read up on those two particular medications to see how they might affect your cycle.