Day 12 of the menstrual cycle
In short: what happens on day 12?
Day 12 of the menstrual cycle is when oestrogen approaches its peak and the chance of pregnancy is high. The dominant follicle reaches about 18 mm. Cervical mucus becomes slippery and stretchy, like raw egg white – one of the most reliable natural signs that ovulation is near.
Day 12 of the menstrual cycle – animated explainer
Day 12: 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
Follicular phase
Chance of pregnancy
High
Uterine lining
9.5 mm
Follicle
18 mm
FSH
32
LH
27
Oestrogen
90
Basal body temperature
36.32°C
What is happening in your body today?
The uterine lining is 9–10 mm. The follicle enters its final stage of maturation.
Hormones
Oestrogen nears its peak; LH may start to rise.
How you might feel
Discharge increases; some people notice breast tenderness and a higher sex drive.
Chance of pregnancy
The chance of pregnancy is high.
Tips for today
- If you are trying to conceive, today is a very good day to have sex
- If your ovulation test is positive, ovulation will happen within 24–36 hours
- Drink plenty of water
When to see a doctor
See your doctor if you have severe pelvic pain, nausea and vomiting, or a fever.
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
What does egg white discharge mean?
It is slippery, stretchy mucus produced under the influence of high oestrogen; it helps sperm move and shows that ovulation is approaching.
Can you get pregnant on day 12 of your cycle?
Yes. In a 28-day cycle, day 12 is one of the most fertile days.
What are the signs of ovulation?
Common signs include slippery, clear discharge, a positive ovulation test, mild one-sided pelvic pain, breast tenderness and a higher sex drive.
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