Day 4 of the menstrual cycle
In short: what happens on day 4?
Day 4 of the menstrual cycle is when bleeding becomes noticeably lighter and oestrogen begins to rise. As the uterine lining approaches its thinnest point, the growing follicles in the ovaries produce more oestrogen. Many people notice that their energy levels and mood start to improve around this time.
Day 4 of the menstrual cycle – animated explainer
Day 4: cycle dial, uterus and ovaries, hormone levels (illustrative animation).
What the animation shows
- FSH
- Follicle-stimulating hormone: starts the growth of follicles in the ovary
- LH
- Luteinising hormone: its sudden surge triggers ovulation
- E2
- Oestrogen (oestradiol): thickens the lining of the uterus
- P4
- Progesterone: prepares the uterus for a possible pregnancy
- BBT
- Thermometer and dots below: basal body temperature
- RING
- Coloured ring: the 28-day cycle and its phases; the green arc marks the fertile days
- MM
- The measurement in the uterus shows lining thickness; in the ovary it shows follicle or corpus luteum size
Phase
Menstrual phase (period)
Chance of pregnancy
Very low
Uterine lining
2.5 mm
Follicle
6 mm
FSH
52
LH
18
Oestrogen
19
Basal body temperature
36.31°C
What is happening in your body today?
Shedding of the uterine lining is largely complete. As the follicles grow, the ovary becomes more active.
Hormones
Oestrogen slowly rises; FSH is still high.
How you might feel
Cramps usually ease or stop. Energy and concentration start to improve.
Chance of pregnancy
The chance of pregnancy is very low.
Tips for today
- Eat a balanced diet with enough protein and fibre
- You can gradually increase the intensity of exercise
- Choose lighter period products for the last days
When to see a doctor
See your doctor if your period lasts longer than 7 days every month or if you bleed between periods.
Menstrual cycle day by day: table
| Day | What happens | Fertile window |
|---|---|---|
| Day 1 | First Day of Your Period | — |
| Day 2 | Heaviest Bleeding Day | — |
| Day 3 | FSH Rises, Follicles Grow | — |
| Day 4 | Bleeding Eases, Oestrogen Rises | — |
| Day 5 | Last Day of Your Period | — |
| Day 6 | Follicular Phase Begins | — |
| Day 7 | Dominant Follicle Is Selected | — |
| Day 8 | Oestrogen Rises, Fertile Window Nears | Low |
| Day 9 | Fertile Window Begins | Moderate |
| Day 10 | Fertile Window, Higher Pregnancy Odds | Moderate |
| Day 11 | 3 Days Before Ovulation | High |
| Day 12 | Oestrogen Nears Its Peak | High |
| Day 13 | LH Surge: Ovulation Is Near | Highest |
| Day 14 | Ovulation Day | Highest |
| Day 15 | Luteal Phase Begins | Moderate |
| Day 16 | Progesterone Rises | Low |
| Day 17 | Luteal Phase and Increased Appetite | — |
| Day 18 | Breast Tenderness May Start | — |
| Day 19 | Implantation Window Opens | — |
| Day 20 | Implantation Bleeding Possible | — |
| Day 21 | Progesterone Peak (Day 21 Test) | — |
| Day 22 | Mid-Luteal Phase | — |
| Day 23 | PMS Symptoms May Start | — |
| Day 24 | Hormones Start to Fall | — |
| Day 25 | Late Luteal Phase and PMS | — |
| Day 26 | Progesterone Drop and Cramps | — |
| Day 27 | 1 Day Before Your Period | — |
| Day 28 | Last Day of Your Cycle | — |
Frequently asked questions
How many days does a normal period last?
A normal period lasts between 2 and 7 days. For most people it lasts 4–5 days.
Is it normal for your period to stop on day 4?
Yes. A period that ends on day 3–5 is within the normal range.
Can you get pregnant on day 4 of your period?
The chance is low. However, ovulation can come early in short cycles and sperm can survive for up to 5 days, so the risk is not zero.
Gynaecology check-ups and follow-up at SoftCare Clinic
Book an appointment with our specialist doctors for irregular periods, painful periods or pregnancy planning.
The information on this page is general guidance based on a typical 28-day cycle and does not replace a medical examination. It should not be used as a method of contraception.
Medical content editor: Op. Dr. Şükrü Sanus