When does PMS start?
PMS usually starts 5 to 10 days before your period, in the second half of the luteal phase after ovulation. For some people it begins as early as two weeks before, right after ovulation, and for others only a day or two before. Your own start day tends to be fairly consistent, so tracking a few cycles shows when yours begins.
Why PMS starts after ovulation
PMS is tied to the luteal phase: the time between ovulation and your period. After ovulation, progesterone rises; in the last week or so, progesterone and estrogen both fall. Symptoms usually appear as those hormones shift, which is why PMS doesn't happen in cycles where you don't ovulate, during pregnancy or after menopause.
Work out your likely PMS start day
- Find your next period date with the period calculator.
- Count back 5 to 10 days. That's the usual PMS window.
- If your cycles are long, your PMS starts later in the cycle (but still about a week before bleeding).
- Log a quick mood and symptom check-in each day for two or three cycles to find your real start day.
| Cycle length | Ovulation (approx.) | PMS often starts around |
|---|---|---|
| 26 days | Day 12 | Days 16 to 21 |
| 28 days | Day 14 | Days 18 to 23 |
| 31 days | Day 17 | Days 21 to 26 |
| 35 days | Day 21 | Days 25 to 30 |
Common first signs
Most people have a personal first sign. For some it's sore breasts or a breakout. For many, it's emotional: a shorter fuse, feeling flat, or worrying more. Others notice cravings or poorer sleep first. See the PMS symptoms list and signs your period is coming.
When you know PMS usually starts on day 22, you can plan: fewer late nights, lighter meetings, easy meals, and a heads-up to people close to you.
When PMS starts too early
Symptoms that start right after ovulation and are severe for two weeks every cycle can be a sign of PMDD. If symptoms start even earlier, or never really go away, they may be something else that gets worse before your period. See PMS two weeks before your period.
See a doctor if PMS starts two weeks before your period and disrupts your life, or if symptoms are there all month. If you have thoughts of harming yourself, call your local emergency number now, or in the US call or text 988. In the UK, Samaritans are on 116 123.
Frequently asked questions
Can PMS start two weeks before your period?
Yes, for some people it starts right after ovulation. If it's severe for that long every cycle, ask a doctor about PMDD.
Can PMS start right after your period?
No. Symptoms in the week after your period are not PMS. They may be another condition, or a different part of your cycle.
Does PMS start on the same day every month?
Roughly, if your cycles are regular. It moves later if ovulation is late.
How long does PMS last once it starts?
Usually 5 to 10 days, easing within about four days of bleeding. See how long PMS lasts.
Sources
- Office on Women's Health: Premenstrual syndrome (PMS)
- Cleveland Clinic: PMS (premenstrual syndrome)
- NHS: PMS (premenstrual syndrome)
This page is for information only and isn鈥檛 medical advice. If something worries you, please talk to a doctor.
Keep reading
How long do PMS symptoms last?How long does PMS last? Usually 5 to 10 days before your period, easing within about 4 days of bleeding. The typical timeline and when it lasts too long.
What are the most common PMS symptoms?PMS symptoms: the full list of emotional and physical signs, from irritability and crying to bloating and cravings, when they start, and when to get help.
Period calculator: when is my next period?Free period calculator: enter the first day of your last period and your cycle length to see your next 6 periods. Private, instant, nothing is stored.
PMS test: do my symptoms follow my cycle?Free PMS test: rate 11 common premenstrual symptoms and see whether yours look like mild PMS, typical PMS or something worth raising with a doctor.
Luteal phase mood: a kind survival guideWhy the luteal phase can bring anxiety, low mood, irritability and tears, when it usually starts, what actually helps, and when it might be PMDD.