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 azithromycin and cefalexin tablets and my period started 5 days i started the medication, and that was abnormal, I have a 26 day cycle and it started on 18 days, and the flow was normal 3 days as I used to have it and after another 18 days (that’s today 12/10/2017), it started again . Although I have sex during this medication. Please could that be because of those drugs, if yes, will my period ever return to normal?
Hello Francisca, this might be as a result of the anti-biotic taken, anti-biotics are known to delay or modify a female’s period, however this won’t last for long.
Thanks a lot.
Beth
I took ampiclox during my period and my period hasn’t stopped since then could it be as a result of the ampiclox?
Hi there Betty, yes this is more than likely as a result of the anti-biotics.
Hi I haven’t seen my period since last two months…I went for test which came out I had pelvic inflammatory diseases….have been on drugs for a week now but I haven’t seen my periods….please what could be the reasons…I need reply urgently
Hello there Tolupe, please correspond with your doctor re this especially if you were told that medication was suppose to start periods.
Started Azithromycin on the 25 of sep now I’m 3 days late but I did have unprotected sex with my bf during this time could I be pregnant or could it be the antibiotics?
Hello Jay, yes this could be as a result of the anti-biotics.
Hi there. I took levofloxancin this month because I was sick. I took it for sick days starting on the 18th of Spetember. I was predicted to start my cycle somewhere close to the 20th-24th. I did not get a period at all this month and still have not gotten one. My breasts are aching like crazy to the point where it hurts to walk and I’m having all the symptoms of a period. I need to know if the antibiotic is what is causing this and when I should expect another cycle. Thank you
Hello Emily, the anti-biotic might be responsible for your menstrual delay.
I’m 48 and have tooth infection. Dentist put me on amoxicillin and i started spotting light pink for 3 days then got it my normal period 4 days then back to light pink 3rd day not stopping. This has never happened before. Could it be my age ??
Hi there Regina, the amoxicillin as an antibiotic could be responsible for this.
Does ampiclox serve as a contraceptive
Hello Nkem, no, this is an antibiotic used to treat infections.
I have a stye in my eye and I went to the doctor got some antibiotcis and ibuprofen 800mg 3xs a day I started medication 2days before I was supose to get my period I read that ibuprofen stops periods but I still getting slight cramps Should I be fine of should I go to the doctors ?
Hello Cynthia, the antibiotics is more than likely the reason for this.
I took ampicillin twice daily for 4-5 days. Now I am 3days late but had unprotected sex twice during the intake and a day after. Could it be the effect of drug or pregnancy?
Hi there Gift, the taking of antibiotics causes the delay of the period, so this may be the cause.
Hi… I took erythromycin tablet for a week. I did not get my menstruation. Is this because of this tablet? I am unmarried and 28years old
Hello Mary, yes this antibiotic might have delayed your menses.
I had to take a total of 5 courses of antibiotics (1 course on one antibiotic and 4 courses on another), and I am almost two weeks late, can the antibiotics make me skip a period? Also if the antibiotics don’t contain penicillin, are the effects different?
Hello Jess, anti-biotics do delay the period, see link below to read more on this: https://womanjunction.com/antibiotics-and-menstrual-cycle/
Hi i started my period on Wednesday morning,it was flowing well,then i got sick and was on drugs,the blood was still flowing till Thursday then immediately i started the antibiotics tablet on friday,it was just a spot of blood i saw through out the whole day.my period lasts for 5days so the remaining two days nothing came out and yes i have been taking the antibiotics 3times daily as prescribed..could it be the antibiotics cause i think it has happened before also when I got sick some months ago and I took a drip with antibiotics..my period just stopped.
Hello Cynthia, yes it is more than likely that this was caused by the anti-biotics.
Started cephalexin on day 1 of my normally 5-day period. My period lasted for less than 3 days and then became light spotting, then nothing. Could this be due to antibiotics that soon, or just weird period? Also, will my period start right away again after i finish the pills?
Hello there Nic, yes, the taking of anti-biotics might be the culprit for this.
Hi i took agumentine tabletsfor 7 days and fluconazole for the treatment of an infection last month. And had unprotected sex with my boyfriend 1 wèek before my menses. Now my menses is out and it only lasted for 2 days instead of 5 days and it was scanty, could it be am pregnant or its the drugs?
Hello Obele, this could mean either. Anti-biotics are known to disrupt the menstrual cycle however you did have unprotected sex. You have to wait and see.
I am currently 12 days late for my period. I’ve been on a course of amoxicillin and then had strep. Where the doctor prescribed me with penicillin . I took it for a week and realized I had been taking it wrong and stopped for a week until I saw my dr again. He told me to finish the antibiotics so I was back on it for another week double the dose. I’ve never been this late for a period and I’m not trying to conceive! I’ve taken three pregnancy tests but all negative. Can anyone tell me how long it took for your period to come back ? Its so delayed I’m getting worried because there’s all these threads with girls getting negative results but actually end up pregnant!! Any advice is great!
Hello Selena, anti-biotics are known to delay the cycle and this might be what is happening to you. See link below to read more about this: https://womanjunction.com/antibiotics-and-menstrual-cycle/
I started taking antibiotics on Tues., then my menstruation came out the next day… could that (Menstruation) make the drugs less effective???
Hello Iphie, having your period is not linked to making antibiotics any less effective.