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, I was on amoxicillin AB, 3rd week of October . I was in sexually active in the night of the 4th of Nov I took morning after pill. But the 4th week of October I started having bloody discharge as though I was going to have my period. Haven’t had my period since then. I’ve done PT but it was negative. My boobs are sore as per normal when I would get my period
Hi there Heather! You should consult your doctor for this. Regards
I see everyone else commenting, so I’ll ask away. I started taking “Amox-Clav” antibiotics the day or so before my period was due. It’s been two days, could it be the antibiotics messing with me? I’ll likely call my doctor.
Hi there Victoria! Thanks for your comment!
Not all of the antibiotics interact with your period directly. But you should call your doctor to ask whether its affecting your periods or not. Regards
I started taking antibiotics on the day I was supposed to start my period it was then two days late. My period is normally four days long it is now on day eight. I have not been sexually active for two months.
Hi there Sydney! Antibiotics can mess up with your periods. But still you should seek medical advice on this antibiotics you are taking. Regards
hi I had antibiotics for three days the two days later I had spottings which lasted for 3 days just like my usual periods ….I tested 9 days after my periods where done and it came out negative can it be becouse of the antibiotics?
Hi there Jessy! Yes, it could be the antibiotics causing this. Regards
Hi! I had antibiotics for 2 weeks from the 5th day of my mensuration and i am 10 days late for periods. Can antibiotics be the cause or is it possible for pregnant ?
Hi there! Yes, Antibiotics can affect your menstrual cycle. The condition you are experiencing might be because of those antibiotics. Regards
I have stopped taking pills last September 7, 2016.
I became sick & took erythromycin on the last week of September.
I am sexually active.
My LMP is September 12, 2016.
Today is 02 November 2016 and still I havent got my period
I had 2 PTs already but all negative.
I wonder why it is happening to me
Hi there Juliana! You should visit a doctor and get yourself checked. Regards
Hi im cynthia. I had UTI and took antibiotics for women for 7 days, havent seen my period for 10 days. Is it possible that i am pregnant?
Hi there Cynthia! The cause of your delayed period might be the antibiotics you are taking. You should ask your doctor about it. Regards
Hi i recently went to the hospital and found out i had a UTI now ive been taking antibiotics for 8 days I’m 8 days late. Would the antibiotics be the cause of my missed period?
Hi there Dominique! Yes that might be the antibiotics that are delaying your periods. Regards
I have been taking amoxil for 4 days now and am 2 days late. Can that be the cause?
Hi there! Yes, that might be delaying your periods. Regards
Hi I have taking amoxicillin for five days now.haven’t seen my period and yet don’t feel pregnant. can the antibiotics be the cause of the delayed period plz
Hi Maa Adwoa, There’s no scientific link between most antibiotics and the menstrual cycle. It might be the stress that is triggering your period. You should really get a medical advice on this. Regards
Good day, I have been taking antibiotics for a prolonged period due to reinfection, my period came 5 days late and on the 2nd day a thin membrane like structure came out on my period, its a bit smelly. Should I be worried or its just that the dose was too much. Tia
Hi Michelle, this isn’t normal.You should really get a medical advice. Regards
Am Aderonke..
I took Doxycycline antibiotics since 4days ago now and I supposed to seen my period yesterday I didn’t see it till now. So am confuse can antibiotics stopped my period.
Hi Aderonke, Not every antibiotic can delay your period. It can stress, diet changes, hormonal imbalances etc, that is disturbing your menstruation. You should really get a medical advice on this. Regards
Hi am Sonia thanks for your help, please can antibiotics prevent me from getting pregnant because i am taking some antibiotics i have tried using test strip but it came out negative but i am yet see my period. And please i want i want to know how long it takes before test strip can detect pregnancy
Hi Sonia, Thanks for your comment!
Pregnancy tests are most reliable from the first day of your missed period, although some tests can be used as early as four or five days before your period is due. But to have an accurate test, you should take a pregnancy test after 14 days of missed period. Regards
I took lymph capsules 250mg 3days after my period on 18Aug. till now Oct.6 I have not see my period is this wrong is going to be permanent
Hi Ukamaka, Thanks for your comment!
Antibiotics can surely change your menstrual cycle. You should get your periods soon. Regards
Hello,
I suffered from high fever and cough and cold twice in a month and so I had to take antibiotics zofacin 500 twice in a month…its been over 40 days i had my period..is it due to antibiotics?
Hi Poulami, the period delay you are experiencing might be because of antibiotics. You should visit a doctor now and get yourself checked. Regards
I think this is off topic, but I was prescribed some penicillin, 3 times a day, earlier I was masturbaiting and it was only clitoral, when I went pee after and I wiped I noticed the fluid my vagina pushed out was very very thick for come. Almost like a thick snot. So I was wondering if the penicillin could be effecting my secretions?
Hi Yung Lean, Thanks for your comment!
It might be because of the antibiotic. You should visit a doctor now and get yourself checked. Regards