At a glance
- The urge to leave often peaks in the week before your period and eases within days of it starting.
- This fits PMDD symptoms like rejection sensitivity and mood swings, not proof the relationship is actually failing.
- Delaying any big decision for 24 to 48 hours keeps your options open until the hormone drop passes.
- A 2024 cohort study of over 15,000 women in Sweden found PMDD specifically linked to a modestly higher rate of relationship breakup among married or cohabiting women (IRR 1.22, Journal of Affective Disorders); severe PMS alone showed no such link.
- If the pattern repeats every month and keeps costing you trust, daily symptom tracking for two cycles helps a doctor confirm whether it fits PMDD.
What's happening in your body right now?
In the week before your period, estrogen and progesterone both drop. For most people that drop passes without much notice. For people with PMDD, the same drop can turn ordinary annoyance into a conviction that the relationship itself is the problem.
Wanting out, feeling rejected over something small, or replaying every flaw in your partner are recognized PMDD symptoms, not a verdict on your relationship. DSM-5-TR lists mood swings and rejection sensitivity among the core symptoms, and relationship doubt often rides along with them.
This doesn't make the feeling fake. It means the timing matters more than it seems like it does in the moment. If the urge to leave shows up in the same week every month and eases once your period starts, that pattern itself is useful information, separate from whatever the fight was actually about.
What can you do in the next 60 seconds?
Name what's happening before you act on it. Something like, 'this might be the week before my period talking' doesn't erase the feeling, but it buys you a beat before you say something permanent.
Next, change what your body is doing. Run cold water over your wrists or hold an ice cube for 30 seconds. Breathe out for six counts, longer than you breathe in, for a full minute. Breathing exercises for PMS explains why the long exhale helps slow things down.
Then leave the room if you can. Tell your partner you need 20 minutes and that you're coming back. You're making sure you're the one steering the conversation, not the week before your period.
What should you say, and what should you not say yet?
Say the feeling without the verdict: 'I'm having a hard time right now and I don't trust my read on us today.' That's true, and it doesn't commit either of you to anything.
Hold off on 'I want to leave,' 'I don't love you anymore,' or anything about ending things for good. Those are the sentences hardest to take back, and the week before your period is the least reliable week to decide them.
If you're about to type something you'll regret, about to send a text you might regret and rewrite a heated message before you send it both walk through slowing down before you hit send.
Niyora is a PMS and PMDD support app. Its Moon feature lets you write down what happened, see it from your partner's side, and draft a reply you can hold for 20 minutes before you decide whether to send it.
How do you repair afterwards?
Once the urge has passed, go back to your partner. Name how it felt to say it, instead of replaying the whole fight. 'I meant that I was overwhelmed, not that I want out' names the gap between the moment and the relationship.
Skip the long apology that walks back through the whole fight. One honest sentence about what was true (you were struggling) and one about what wasn't (you don't actually want to leave) does more than ten minutes of explaining your hormones.
After the blowup: how to repair covers what to say when you're the one who needs to come back first, and what to do if your partner needs more time to come back than you expected.
How can you plan for next cycle together?
Pattern beats surprise. If you can both see it coming, it stops feeling like a referendum on the relationship every single month.
Mark the week it tends to happen on a calendar you both see, and tell your partner ahead of time: 'next week might be hard for me, not because of us.' How to explain PMDD to your partner has language for that conversation when you're not already mid-fight.
Agree on one phrase either of you can say to pause things, like 'can we take 20.' Agree together, outside the hard week, that it means a break and not a shutdown. Write it down somewhere you'll both remember it exists before the week you need it.
When is it time to get more help?
A monthly urge to leave that keeps costing you real relationship trust is worth more than a cold water reset. Daily symptom tracking across two cycles is how a doctor confirms whether this fits PMDD, rather than ordinary premenstrual tension or something present all month that just gets worse beforehand.
Mood swings and relationship doubt that don't ease once your period starts, or that show up outside that one week, are worth mentioning to a doctor too. A systematic review found that among women with bipolar disorder, the proportion who also met criteria for PMDD ranged from 27% to 76%, far more than in the general population (2022, The Journal of Clinical Psychiatry). That overlap is one reason a doctor may ask about your mood across the whole month, not only the week before your period.
If this takes a week of every month, or you have thoughts of hurting yourself, see a doctor and bring two months of daily notes. PMDD hopelessness: what it feels like and what helps is a good place to start if the low mood lingers longer than the doubt about the relationship does.
From the research library
Research on mood swings
116 studies in the library look at mood swings in PMS and PMDD. They were published from 1971 to 2026, and each one is summarised in plain English.
116
studies, 1971 to 2026
How strong the studies are
- Strong study design
- 6
- Moderate study design
- 41
- Early or limited evidence
- 69
Study, 2026
How do women with PMDD process emotions differently in their brains?
Women with PMDD show increased activity in emotion-processing brain networks, especially during the luteal phase, and this baseline difference even appears in the follicular phase and relates to symptom severity.
Strong study design
Case-control study, 2026
Do women with PMS handle emotions differently at different times of the cycle?
Yes. Women with PMS tend to use emotion coping strategies that make symptoms worse (like dwelling on negative thoughts) and fewer strategies that help (like accepting difficult thoughts). These patterns change across the menstrual cycle.
Strong study design
Systematic review, 2025
Do people with PMDD and severe PMS have difficulties with emotion regulation?
People with PMDD and severe PMS may have difficulties identifying emotions and choosing how to handle them, particularly using rumination (replaying upset thoughts) in the late-luteal phase. Evidence remains limited.
Strong study design
Systematic review, 2025
Does teaching adolescent girls about their menstrual cycle and health help reduce period pain and PMS?
Yes. A systematic review of five good-quality studies shows that psychoeducation (structured teaching) significantly reduced period pain and PMS symptoms and improved emotional wellbeing in adolescent girls.
Strong study design
Randomised trial, 2007
Does paroxetine work better if taken daily or just during your luteal phase for PMDD?
Daily paroxetine had an 85% response rate and was most effective overall, while luteal-phase-only paroxetine worked equally well for irritability and mood swings but was weaker for depression and physical symptoms. This well-designed study provides reliable results.
Strong study design
Survey study, 1994
How many different ways do researchers measure PMS in clinical trials?
Researchers use many different measurement tools across studies. 65 different questionnaires were found in 350 trials of PMS drugs, making it hard to compare whether treatments actually work.
Strong study design
Questions people ask
Is wanting to leave every month a sign of PMDD?+
A monthly urge to leave that shows up in the week before your period and eases within days of it starting can fit a PMDD pattern. A pattern alone isn't a diagnosis. PMDD is confirmed with daily symptom ratings over at least two cycles, not by how one month felt.
Should I make relationship decisions during PMDD?+
Big relationship decisions made during the week before your period are worth delaying until a few days after it starts. PMDD can turn ordinary friction into a conviction that you need to leave, and that conviction is far more reliable once the hormone drop has passed.
Does PMDD increase the chance of breaking up?+
PMDD doesn't guarantee a breakup, but a 2024 cohort study of over 15,000 women in Sweden found PMDD linked to a modestly higher rate of relationship breakup among married or cohabiting women (IRR 1.22, Journal of Affective Disorders). The increase was small, not inevitable.
What should I say instead of 'I want to leave'?+
Relationship doubts before your period are easier to manage if you name the feeling without the verdict: 'I'm having a hard time right now and I don't trust my read on us today.' That buys you time without committing either of you to a decision you might not mean next week.
When should I see a doctor about relationship doubts before my period?+
A doctor can help if relationship doubts before your period take a week of every month, or if you have thoughts of hurting yourself. Bring two months of daily notes on your mood and your period so the pattern is easy to see.
Sources
- 1.Relationship of Premenstrual Dysphoric Disorder With Bipolar Disorder: A Systematic Review, The Journal of clinical psychiatry, 2022
- 2.Association between severe premenstrual disorders and change of romantic relationship: A prospective cohort of 15,606 women in Sweden, Journal of affective disorders, 2024