Day 17 of the menstrual cycle
In short: what happens on day 17?
Day 17 of the menstrual cycle falls in the first week of the luteal phase. Progesterone keeps rising and slightly increases body temperature. Because your body needs a little more energy, your appetite may increase. If fertilisation has occurred, the embryo is nearing the end of its journey towards the uterus.
Day 17 of the menstrual cycle – animated explainer
Day 17: 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
Luteal phase
Chance of pregnancy
Very low
Uterine lining
12.5 mm
Corpus luteum
22 mm
FSH
24
LH
22
Oestrogen
42
Basal body temperature
36.72°C
What is happening in your body today?
The uterine lining develops more blood vessels and begins to produce nourishing secretions (secretory phase).
Hormones
Progesterone rises; oestrogen increases slightly again.
How you might feel
You may feel hungrier, slightly bloated and in need of more sleep.
Chance of pregnancy
The chance of pregnancy is very low.
Tips for today
- Wholegrains and protein help you stay full for longer
- Limit sugar and processed foods
- Balancing exercise such as yoga and Pilates may feel good
When to see a doctor
See your doctor if you have unusual bleeding or severe pain.
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
Why am I so hungry before my period?
In the luteal phase, progesterone slightly speeds up your metabolism and can increase your appetite.
Can you get pregnant on day 17 of your cycle?
In a regular 28-day cycle, the chance is very low.
When does fertilisation happen?
Fertilisation takes place in the fallopian tube within 12–24 hours after ovulation.
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