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
I took augmentin for my cough but on the second day of my dosage started seeing my period and it was only 13 days after my last period. Is this because of antibiotics or should I consult a doctor?
Hello Ida. A strong dose of antibiotics can sometimes affect periods. You should definitely consult with your doctor for clarification.
I had sex on my ovulation last month, took antibiotics 500mg in 3 days. Now my period was meant to show up on the 13th of this March, it started and stopped immediately. Am I pregnant or did the antibiotics affect my period?
Hello, I took in some Amoziklav for my wisdom teeth some few days ago. My flow started yesterday but it’s not coming well. It’s just some tiny drops. Could it be the medicine?
I started taking amoxicillin on March 3rd, I expected to see my period on the 7th. I’m normally 100% on time all the time, I know from this page the antibiotics can interfere, I was curious if there was any way to gauge when I should maybe start to expect my period to start..maybe a day or 2 after I’ve completed my run of antibiotics? I’m on 500mg 3x a day of amoxicillin for strep.
Hi Sierra, there is no way to calculate it exactly, as everybody reacts different and there are a number of other factors, such as age, health habits, medical history.
Am flowing at the moment, please is it advisable to take antibiotics at same time?
Hello. Although antibiotics can have an impact on the menstrual cycle, the benefits of the antibiotic probably outweigh the effect of the antibiotic on your cycle. You should consult your doctor.
hi i had UTI and i was prescribed levofloxacin for ten days,my period was supposed to come on 4th but still no signs,could this be due to the levofloxacin?
yes, it’s possible that the medicine affected your cycle
I got a tooth extracted and I was given some antibiotics. While taking the antibiotics I started seeing my period that I was not supposed to see cause I saw it 2 weeks ago. However am still seeing my period and it’s like 3 weeks now. I’m so worried now the only thing I can think of is it the antibiotics that caused this? I will be going to see my doctor.
Yes, you must consult your doctor. While antibiotics can throw off a cycle, the prolonged bleeding should be checked out.
I took the generic brand of z pack in the beginning of February. Now my period is 20 days late. My cycle was like clockwork prior to taking the medication. Does anyone know when the cycle will start again? I’m hoping it just affected the one cycle and will go back to normal!
I took azithral on 30th and then on 1st but did not take the 3rd dose. which means my consumption for antibiotics was wrong ..
I was supposed to have my periods on 3rd but it haven’t started yet..
Can wrong dosage of antibiotics affect periods?
Hi,Antibiotics can affect periods yes depending on the antibiotics and the dosage.
I’m currently taking Augmentin Duo Forte & Solone for Bronchitis. I just find finished taking Amoxicillin. My period is due. Will it effect my period?
Hi, Some medications can affect your period coming late or even earlier than usual.
I’ve been taking amoxicillin for an ear infection and I’m 15. My periods are usually irregular anyway but right now my period is super light, I’m not even able to use a mini tampon let alone a regular! Hope this helps
I had a serious urine infection for almost two weeks and had to take antibiotics for 2 weeks as well. My period was supossed to arrive 5 days ago but still nothing. The antibiotics can delay the period this much or should I see a doctor? Thanks!
Yes, the antibiotics can affect the flow of your period. Read this post from our website for more information dhttp://womanjunction.com/antibiotics-and-menstrual-cycle/
Can antibiotics have any effects when I’m on periods ?
I took antibiotics due to flu and subsequently started having my periods. But after Day 1 I stopped having any flow at all. Is it related to my antibiotic prescription ? Should I consult a doctor about it?
Hello,If you’re taking antibiotics for an illness, it may affect your menstrual cycle. Most women experience no change, but a heavy course of antibiotics can delay your period.
Hello,yes all these things along with stress can affect your cycle it will return to normal though it just takes a while try not to stress,if you become too worried you can always call and ask for a test.
I had a really bad abscessed tooth that landed me in the hospital… After about 4 days on all kinds of antibiotics cant even count how many they actually tried before they admitted me… Then they had me on all kids of stuff pain killers and all the above then i had to have surgery to remove the tooth the 23rd of December i usually start my period on the 7th of each month and i haven’t started at all but I’m having the pms and all the stuff but now i have nausea all the time morning and night…. Could all the stuff that went on could that cause the delay in my cycle? Its been way over a month since my last cycle should i call and ask for a test or just wait it out?
I am on antibiotics for recovery from a nose and tonsil surgery that I had about a week ago. I got my cycle yesterday but it’s very heavy. Does this mean it might end sooner? And does this also happen due to the medication.
Hi, Lots of things can affect your menstrual period,antibiotics can affect your cycle too this is normal and not usually a cause for concern as your body will go back to normal.
I have regular menstrual 28-days cycle. My last month period on 11th Dec, i was expecting this month would come on 7th Jan. But i took few antibiotics on 27-31th Dec. because i got terrible sick. This month period came on 14th (yes, just now). So it can totally sure that antibiotics would cause period late.