Menstruation Phase

Day 1 of your period marks the start of a new cycle. The uterine lining sheds because pregnancy did not occur. Typical duration is 3–7 days. Hormones (estrogen & progesterone) are at their lowest.

Follicular Phase

Following menstruation, estrogen rises to stimulate egg follicle growth. This is generally a higher-energy phase. Cervical mucus is minimal and may appear creamy or sticky — not yet fertile-quality.

Ovulation

A surge in Luteinizing Hormone (LH) triggers the release of a mature egg. The egg remains viable for just 12–24 hours. Ovulation typically occurs ~14 days before your next period, regardless of cycle length.

Luteal Phase

After ovulation, progesterone rises to prepare the uterine lining. If no fertilisation occurs, hormone levels drop, triggering menstruation. This phase is relatively stable at 12–16 days for most people.

Signs of Ovulation

• Cervical mucus becomes clear, stretchy, egg-white-like
• Slight rise in basal body temperature (0.2–0.5°C)
• Mild one-sided pelvic cramp (mittelschmerz)
• Increased libido
• Light spotting or breast tenderness

Safe Period Facts

• Sperm can survive inside the body for up to 5 days
• No day is 100% safe without contraception
• The calendar method is ~76–88% effective with typical use
• Stress, illness & travel can shift ovulation timing
• Most reliable when cycles are regular (26–32 days)

Improve Tracking Accuracy

• BBT: Take temperature every morning before getting up
• Cervical mucus: Track changes daily throughout cycle
• OPK strips: Detect LH surge 24–36h before ovulation
• Log at least 6 cycles for reliable pattern data

When to See a Doctor

• Cycles shorter than 21 days or longer than 35 days
• Periods that are very heavy or extremely painful
• No period for 3+ months (excluding pregnancy)
• Spotting between periods frequently
• Trying to conceive for 12+ months without success

Irregular Cycles

Cycles varying by more than 7–9 days month to month are considered irregular. Common causes include stress, thyroid disorders, PCOS, extreme exercise, significant weight changes, and perimenopause. The calendar method is unreliable for irregular cycles — consult a doctor and consider using OPK strips or BBT tracking for better accuracy.