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4 Causes of Period Bloating



5 min read

Causes of Period Bloating

by Team Thinx | 05/26/2024

Whether you’re brand-new to the menstruation process or you’ve been managing your less-than-ideal period symptoms for years now, you’ve likely asked yourself, “Why am I bloated on my period?”

Luckily, there are answers available (and a few sure-fire tips on how to reduce bloating). In this guide, we’re breaking down what causes bloating during period weeks and offering advice from the pros. 

what is period bloating?

If you’re not used to digestive discomfort while you aren’t on your period, you might have a hard time identifying bloating in the first place. If you’re bloated, you might feel:

  1. full – Even if you haven’t been indulging in period cravings, you might still feel overly full—like you just wolfed down a tasty fast food combo meal. 

  2. gassy – Bloating and gas usually have matching friendship bracelets. Bloating can bring an onslaught of farting and burping (again, even if you’re not eating gas-inducing foods).

  3. distended – During bloating phases, you might notice that your stomach is distended—a fancy word for “sticking out more than usual.” This could make your clothes feel a little tighter than they do on a normal day, even if your weight hasn’t fluctuated recently.

Simply put, bloating isn’t fun. But what causes period bloating in the first place and how long can period bloating last?

hormones, hormones, everywhere

Hormones are pulling the strings of your menstrual cycle—but, as it turns out, hormones are also highly involved in gut function.

Every day, hormones in your body interact to influence digestive factors like:

  1. fluid retention – Water is a key ingredient for digestion. We’ll dive into fluid retention in detail in a later section.

  2. food sensitivity – Believe it or not, hormones can impact your sensitivity to specific foods. You might find that some foods wreak havoc on your system only while you’re menstruating. 

  3. motility – Motility describes how quickly food and nutrients move through your digestive system. Hormonal activity can affect your body’s food processing.

Because hormone levels rise and fall throughout your menstrual cycle, these fluctuations can impact your overall gastrointestinal comfort—one potential culprit behind period bloating.


In addition to hormones, your body also produces hormone-like compounds called prostaglandins. Prostaglandins, like hormones, are the busybodies of your system: they communicate with other compounds to direct your body’s key functions. Prostaglandins even play a role in:

  1. contractions – Either during labor or while shedding the uterine lining, prostaglandins can initiate uterine contractions.

  2. ovulation – The specific timing of your egg drop is directly tied to both hormones and prostaglandins. 

  3. hormone regulation – Since hormones and prostaglandins are so closely linked, it's no surprise that they directly interact. 

But what’s their specific role in period bloating? Prostaglandins, like hormones, are also involved in gut regulation: they release or inhibit digestive acid secretion and smooth and contract the stomach muscles.

water retention and period bloating

Let’s return to the topic of water retention: a normal part of your menstrual cycle

Research suggests that fluid retention spikes during your luteal phase. And, yet again, hormones are in the mix: this time, an adrenal hormone called aldosterone, or ALD. To preserve critical minerals like sodium and potassium at a key point in your reproductive cycle, ALD triggers water retention after ovulation and before menstrual bleeding starts. 

Some people may experience extended fluid retention even after their luteal phase ends. And, since water retention can make you feel bloated, this is yet another possible cause of bloating before your period or during your period.

digestive issues and period bloating

Whether you’re no stranger to “period poops” or you’re less regular while on your period, studies indicate a real connection between hormonal activity and digestion during menstruation. There are two key compounds at play in period tummy troubles:

  1. prostaglandins (again) – If your egg isn’t fertilized during ovulation, prostaglandins will instruct your uterus to contract and shed its lining. But since prostaglandins also tell your stomach muscles to contract, this could change your digestive patterns—and potentially cause bloating.

  2. progesterone – Progesterone helps your uterus prepare to host a fertilized egg; it thickens your uterine lining. Progesterone levels spike while your uterine lining is growing, but if your egg isn’t fertilized during ovulation, these levels suddenly drop. This rapid fluctuation is connected with both diarrhea and constipation, and both of these are connected to bloating.

tips for managing period bloating

So, your period bloating might be the result of normal hormone and prostaglandin activity, regularly scheduled water retention, or digestive changes. What now? Let’s touch on some surefire tips to help you kick bloating’s butt. 

#1 hydrate, hydrate, hydrate

When you’re well-hydrated, your body can perform at its best. Ramping up hydration during your period can help you tackle digestive issues specifically; so, if you’re no stranger to the period poops, this is the advice for you.

To make it easier to stay hydrated, try:

  1. Setting alarms – Just like you might set phone alarms to remember to take medications, you can do the same for sipping. If you like to keep your workplace distraction-free, don’t forget about manual timing tools like egg timers and old-fashioned, plug-in alarm clocks.

  2. Getting a big cup – The Stanley cup has taken over the world, and for good reason: keeping a large supply of water on hand makes it even easier to access much-needed hydration anytime, anywhere.

#2 skip trigger foods

There are many possible nutrients that might trigger your body to retain water—every body is different. But scientists have also identified a few widespread retention triggers like:

  1. Salt – Loading up on salty food might signal your body to hold onto more water.

  2. Spice – Capsaicin, the compound that makes food taste spicy, can cause water retention.

  3. Fried food – Since they’re typically high in fat and salt content, fried foods are a common water retention trigger for many.

If you’re struggling with period dehydration or fluid retention is to blame for your cramps, steering clear of these retention-triggering foods might offer relief.

#3 load up on fiber

If you’re struggling to keep your digestive system moving during your period (and irregular poops are making you feel bloated), fiber is about to become your next best friend. You might already be low in fiber: only about 5% of Americans reach their recommended daily value of fiber consistently.

If you’re looking to boost your fiber, you have two options:

  1. supplements – Psyllium husk supplements (like Metamucil) offer a simple, effective way to add fiber to your diet without changing your menu. You can either try a stir-in powder or a capsule.

  2. high-fiber foods – If you prefer to get nutrients from food instead of supplements, turn to fiber-rich ingredients like grains, beans, leafy greens, berries, and nuts.

#4 get comfortable

Whether these tips cure your bloating for good or you still feel a little bloated during your period, comfort is key. One way to boost your overall comfort level during menses is to invest in cozy, functional clothing items—like absorbent period underwear

Similarly to bladder leak underwear, period underwear is designed to:

  1. Quickly and effectively absorb liquid

  2. Prevent leakage

  3. Serve as an alternative to pads and tampons

  4. Keep wearers comfortable—no matter where they are in their cycle

While a high-quality pair of period underwear won’t make the bloating go away, they will offer unmatched comfort and peace of mind.

#5 whip out your yoga mat

Research suggests that physical activity can help alleviate symptoms of bloating. But, if you’re on your period, you might not feel like squeezing in a high-intensity lifting sesh or a long run. Instead, opt for low-impact exercises like:

  1. Yoga and stretching

  2. Tai chi 

  3. Line dancing

  4. A casual stroll

If bloating is the only period symptom holding you back, you’re ready to hit the gym, and you want to crush a new PR, pushing through initial discomfort might help you kick bloating for good. 

#6 chat with your healthcare provider

While many period side effects are perfectly normal, that doesn’t mean they’re easy to deal with. If home remedies and tips don’t make a dent in your debilitating digestive distress, it might be time to schedule an appointment with your gynecologist. 

To make your visit as productive as possible, consider:

  1. writing down your symptoms as you experience them – Journaling about your symptoms in the moment can help you give your provider a complete picture of your needs. 

  2. talking about past efforts – If you’ve already tried changing your diet, drinking more water, and regular exercise, let your provider know. To help you find a solution, they need to know what hasn’t worked in the past.

  3. exploring medication options – Depending on the severity of your bloating (or other side effects), your provider might recommend either a prescription or over-the-counter formula that can help you find relief. If you’re hesitant to add medication to your regimen, try to keep an open mind while expressing your worries to your provider.

If you’re struggling to function during your period, your healthcare provider is in your corner.

unlock menstrual comfort with Thinx

Why do periods cause bloating? The answer is different for everyone—and you’re certainly not the only one struggling with digestive challenges during menstruation. 

When your period symptoms kick in, comfort can seem out of reach. At Thinx, we’re changing the menstruation experience for the better. Our high-quality period underwear offers a solution for anyone looking for leakproof technology, an alternative to traditional menstrual products, and well-deserved comfort. 

Our menstrual products are made for everyone: find your perfect pair now.


National Library of Medicine. Gastrointestinal symptoms before and during menses in healthy women. 

Medline Plus. Abdominal Bloating.

Cleveland Clinic. Bloated Stomach. 

World Allergy Organization Journal. Adverse reactions to food: the female dominance – A secondary publication and update. 

Cleveland Clinic. Prostaglandins. 

National Library of Medicine. Relationship between aldosterone and progesterone in the human menstrual cycle. 

Cleveland Clinic. Aldosterone. 

Cleveland Clinic. Here’s the Deal with Period Poops.

Business Insider. How your period changes your poop and what to do about it, according to an OB-GYN. 

National Library of Medicine. Physiology, Progesterone. 

Beaufort Memorial. Tired of Period Bloating? Here’s How to Manage It. 

Journal of Clinical Investigation. Increased salt consumption induces body water conservation and decreases fluid intake. 

Journal of Hypertension. Oral Dose of Capsaicin Increases Blood Pressure in Healthy Subjects.

Forbes. Water Weight: What It Is and How to Lose It.

American Journal of Lifestyle Medicine. Closing America’s Fiber Intake Gap. 

US Department of Agriculture. Food Sources of Dietary Fiber. 

Gastroenterology and Hepatology from Bed to Bench. The effect of a short-term physical activity after meals on gastrointestinal symptoms in individuals with functional abdominal bloating: a randomized clinical trial. 

by Team Thinx

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