"Oh, she must be on her period." If you've heard this phrase, it might have been said about you (or another woman) getting moody, angry, or upset when you usually wouldn't.
Understandably, hearing that phrase may leave you feeling guilty or worse than before. But the truth is, there could be some scientific reasons behind why you may feel or act a certain way the week before your menses.
If you're concerned about the physical and emotional changes you experience around the time of your period, we've got your back. Here's a complete guide we've put together about PMS and PMDD.
In this guide, we'll explore the different PMS and PMDD symptoms and why they occur. We'll also cover the differences between PMS and PMDD, your treatment options, and when it's best to seek medical advice.
Let's jump right in!
Premenstrual syndrome, or PMS, is a group of physical, emotional, and behavioural symptoms typically occurring a week before your period starts. Usually, symptoms will begin on the 13th day of a standard 28-day cycle, though this may vary from one woman to another [1].
Premenstrual dysphoric disorder (PMDD) is the less well-known cousin of PMS. The symptoms of PMS and PMDD can overlap, but PMDD is the more severe form of PMS [2].
Both PMS and PMDD occur during the second half of your menstrual cycle before your period starts. You'll notice that they reappear during a similar time in each cycle [2].
If you have observed such cyclical mood and physical changes, you're not alone. Data shows that 3 in 4 women of reproductive age experience some form of PMS symptoms. Meanwhile, around 3-8% of reproductive-age women are affected by PMDD, which is much less common [2].
The prevalence of PMS and PMDD marks the first difference between these conditions. The second difference is the severity and impact of their symptoms, which we'll explore further below.
At first glance, PMS and PMDD may seem like twins, mainly because they both share similar symptoms. But upon closer inspection, they're more like cousins, with similar features but some rather striking differences.
Common symptoms of PMS and PMDD can be split into two main categories:-
Affective symptoms are symptoms that involve your mood and emotional responses. Affective symptoms of PMS and PMDD include [2, 3]:-
Somatic symptoms focus more on the physical symptoms. Somatic symptoms of PMS and PMDD include [2, 3]:-
In general, these symptoms should follow a repetitive pattern. They usually begin the week before your period and should improve within four days after your menses start [3].
Remember how we mentioned that PMDD is the more severe form of PMS? This is typically reflected in the number and severity of symptoms you experience.
For your doctor to diagnose you with PMS, you'll only need to experience one somatic and one affective symptom leading up to your period. But for the diagnosis of PMDD, women usually report five or more symptoms in the week before they get their menses [3].
The severity and impact of the symptoms you experience may also differ. Here are some ways they vary [3]:-
Both symptoms of PMS and PMDD can affect your quality of life. However, PMS is often a mild or minor issue for women, whereas PMDD can significantly impair how you go about your day-to-day life [2, 3].
The symptoms of PMS and PMDD can change over the years, but how they evolve differ from woman to woman. These symptoms may improve, worsen, or persist over time.
For instance, one study found that only 36% of women diagnosed with PMS still had clinically significant symptoms a year later [3].
Another study involving over 7000 women found that PMS symptoms could either improve or worsen with age. Some women noticed the worst symptoms just before or around the age of 35, and others around the age of 40-44 [4].
Due to this, it's challenging to predict how your symptoms may alter over the years. They could get better, worsen, or fade away after a certain age.
To date, scientists still aren't 100% sure why some women experience PMS or PMDD while others don't. They've also yet to fully understand the exact mechanism behind these conditions.
Nonetheless, some studies have indicated that the fluctuation in hormone levels is the culprit. The levels of estrogen and progesterone will vary throughout your cycle, and research indicates that these cyclical changes may be the trigger for your symptoms [3].
Researchers also suggest that women who experience PMS or PMDD tend to be more sensitive to these changes in their hormone levels [3].
PMS and PMDD treatment is geared to relieve any physical and mood-related symptoms. Here are some treatment options your doctor may recommend:-
Antidepressants are used to treat PMDD and any severe mood-related symptoms of PMS. The most common type of antidepressant used is the selective serotonin reuptake inhibitor (SSRI) [2].
SSRIs alter the concentration of chemical messengers (neurotransmitters) in your brain and hence, help to improve mood and symptoms of anxiety or depression [3].
You'll typically have to take an SSRI for two or more menstrual cycles to see if it works. Around 60-75% of women will experience some form of benefit from taking an SSRI, but if not, your doctor may recommend an alternative antidepressant [2].
Your doctor may recommend contraceptives for the treatment of PMS or PMDD. Some studies have shown that oral birth control pills may be beneficial in treating both physical and mood-related symptoms. You'll typically take these pills daily with no break in between, and you won't get any periods doing so [2].
Alternatively, your doctor may recommend gonadotropin-releasing hormone agonists (GnRH agonists). These will temporarily prevent your ovaries from producing estrogen and progesterone. In other words, you'll be undergoing temporary menopause, which allows your symptoms to subside. Although these agents are very effective, they can be very costly and lead to side effects like bone loss over time. Therefore, they are usually less suitable for longer-term use [2, 3].
These methods may be recommended if your symptoms are not very severe. Another reason your doctor may recommend them is for treatment alongside medications if you have PMDD. These management options are effective in some women, and a huge plus point will be their low risk of side effects [2].
Some treatment options that do not require the use of medications include [2, 3]:-
It's best to see a doctor when your symptoms begin interfering with your personal life, relationships, or work commitments. If you're constantly feeling anxious, depressed, or dealing with suicidal thoughts, reach out to find a safe space where you can communicate your experience and concerns to a trusted healthcare provider.
Your healthcare provider will typically ask you questions about your symptoms and lifestyle. And they may even recommend keeping track of your symptoms for two or more cycles to make a diagnosis [2]. This helps them differentiate PMS and PMDD symptoms from other conditions with similar symptoms, such as depression and anxiety disorders.
If you'd like a practical, effective, and convenient way to track your cycle and symptoms, the inne minilab can help!
The minilab uses simple saliva tests to track your cycle and changes in your hormone levels. Plus, the app lets you quickly record your daily symptoms and mood. This allows you to learn more about your cycle and correlate it to your symptoms, as well as supports your healthcare professional in providing optimal diagnosis and treatment.
1. Abu Alwafa, R., Badrasawi, M., & Haj Hamad, R. (2021). Prevalence of premenstrual syndrome and its association with psychosocial and lifestyle variables: a cross-sectional study from Palestine. BMC women's health, 21(1), 233. https://doi.org/10.1186/s12905-021-01374-6
2. Casper, R. F. (2021, January 24). Patient education: Premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD) (Beyond the Basics). UpToDate. Retrieved August 15, 2022, from https://www.uptodate.com/contents/premenstrual-syndrome-pms-and-premenstrual-dysphoric-disorder-pmdd-beyond-the-basics
3. Hofmeister, S., & Bodden, S. (2016). Premenstrual Syndrome and Premenstrual Dysphoric Disorder. American family physician, 94(3), 236–240.
4. Dennerstein, L., Lehert, P., & Heinemann, K. (2011). Global epidemiological study of variation of premenstrual symptoms with age and sociodemographic factors. Menopause international, 17(3), 96–101. https://doi.org/10.1258/mi.2011.011028