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’m Jane, I had my last period on 27th June, took Cipro on 9th July. My menstrual cycle calculator said I will see my next period on 21 July but today is 23 and it’s still not in. My breast is tender but have done pregnancy test too and it’s negative. What could be the problem?
Hi there Janet, the use of the antibiotic might have delayed your period.
Hi,I saw my period on the 23 of June,I am suppose to see it on July 20,but its delayed plus I have been on ampiclox for over a week(just stop yesterday), could it be the cause of the delay….pregnancy test is negative
Hello Ema, yes the taking of antibiotics is known to delay a woman’s period.
Hello good day, I saw my last period June 12 and was supposed to see my next period July 9. Not forth coming took a pregnancy test all turns negative… meanwhile am trying to conceive .What do I do please?
Hello there Lily, use the following link to help you calculate your most fertile days and have sex around and on those days. All the best.
https://womanjunction.com/
So, I am a nursing mom, my daughter is 1.5. I took an antibiotic for 7 days for a UTI. They did not help and 2 days after I finished the 7 days they put me on a stronger antibiotic. Well that did the trick, but I am 5 days late. I am thinking it is due to the antibiotics…I was told nursing messes with your hormones making it harder to get pregnant? Do the antibiotics mess with hormones as well. Anything will be helpful. Thank you.
Hi there Amy, yes, the intake of antibiotics might have delayed your period.
Hey. I’m taking septra ds for a uti and my period is 3 days late which doesn’t happen and I’m definitely not pregnant. Could this antibiotic cause this problem I’m having right now?
Hello Latoya, yes the antibiotics seems to be the culprit.
When will regular menstruation come back when taking antibiotics?
Hello Jadeee, periods might be delayed for a few days.
Can amoxicillin cause me to urinate more often than usual? And can it delay my period?
Hello Trendy, please see the following link re the effect of antibiotics: https://womanjunction.com/antibiotics-and-menstrual-cycle/
I had consulted skin doctor for acne. She gave me Minoz tablet
Now i am 8 days late for my period. Can this tablet delay the periods?
Hello Misthi, kindly consult with your doctor to get more information on this.
Hi. I’m Mia. I had my last period June 15 to the 18, had protected sex the 29, went to the emergency hospital on the 30 and they gave me the antibiotic ciprofloxacin. Started the antibiotics July 1. Will it affect my period, meaning will my period be behind since taking the antibiotics?
Hello Mia, yes this might delay the return of your period.
I started my period on Monday and my period stays for just 4 days and today is the 4 the day and its flowing like the first day can it be doxycycline I took on Tuesday???
Hi there Uju, please read the below link on how antibiotics affect the menstrual cycle:
https://womanjunction.com/antibiotics-and-menstrual-cycle/
I took cyprotap for uti then saw my period two days early. Am in the second month and no period could it be the antibiotics is affecting my cycle? I have a regular cycle
Hi Kim, yes the antibiotics is more than likely responsible for this.
please I’m on the family planning injection called Depp provera and I’m having spotting please if I take in amoxicillin will it stop the spotting or it will continue please help me.
Hi there Vivian, if this birth control keeps causing continuous spotting then see your doctor and ask for them to recommend a different birth control.
Hi, I’m Erion I had my last period on 13 June expecting the next for July 10, had unprotected sex on the 12th day of my cycle but took contraceptive. had pre mentrual symptoms and I have had two pregnancy tests(urine) its negative and I had a blood test yesterday(9 July) it came out negative and no period yet.
Hi there Erion, please repeat pregnancy test 7 days after missed period.
So I’m only 18 days into my cycle and started early today. I’m taking clindamycin for bacterial vaginitis and had to take out my nuvaring after only a week…I think the combo of everything cause me to start almost 2 weeks early.
Hi there Dee, yes this might be a possibility for what’s currently happening with you.
Hey I’m on antibiotics called app-sultrafrim 2 months and no periods
I didn’t even know antibiotics can delay my periods😒
I had a medical abortion it was successful
I bleed for one week plus 5 days I discovered quite early, after then I took antibiotics and I had a uti treated, I am supposed to get my period but nothing yet! I took a pregnancy test it came out negative please when does ovulation start after an abortion?
Hi there Nessa, a period typically returns 3-6 weeks after an abortion. Please follow the below link to read more.
https://womanjunction.com/menstrual-cycle-abortion/