Period Delay & Missed Period
Calculator
Calculate how many days late your period is, evaluate the 6 most common physiological causes, and get evidence-based medical advice.
Period Delay & Missed Period Calculator
Calculate how many days your period is late and receive personalized medical guidance based on cycle length and symptoms.
6 Most Common Medical Causes of Late Periods
1. Emotional or Physical Stress
High stress elevates cortisol, which can temporarily suppress the hypothalamus — the brain region that regulates gonadotropin-releasing hormone (GnRH) and triggers ovulation.
2. Polycystic Ovary Syndrome (PCOS)
PCOS causes elevated androgens and irregular ovulation, often leading to missed cycles, skipped months, or unpredictable bleeding intervals.
3. Thyroid Imbalance (Hypo / Hyperthyroidism)
The thyroid gland controls metabolism and interacts directly with ovarian hormone secretion. Both underactive and overactive thyroids cause period delays.
4. Rapid Weight Fluctuations or Low BMI
Significant weight loss, restrictive diets, or excessive athletic training can lower body fat below the threshold needed for regular estrogen production, causing hypothalamic amenorrhea.
5. Hormonal Birth Control
Starting, stopping, or switching birth control pills, hormonal IUDs, or emergency contraception (morning-after pills) frequently alters cycle timing.
6. Early Pregnancy
If you are sexually active, a missed period is the most common early indicator of pregnancy. Taking a home urine test starting day 1 of your missed period provides ~99% accuracy.
Explore Related Cycle & Health Tools:
Medical Sources & References
- American College of Obstetricians and Gynecologists (ACOG). FAQs: How to Tell When You Are Pregnant.(ACOG)
- American College of Obstetricians and Gynecologists (ACOG). FAQs: Amenorrhea: Absence of Periods.(ACOG)
- American Society for Reproductive Medicine (ASRM). Current evaluation of amenorrhea: a committee opinion (2024).(ASRM, 2024)
When to See a Gynecologist for a Delayed Period
- •Period is delayed by more than 14 days with negative pregnancy tests.
- •Fewer than 9 periods in a 12-month period (Secondary Amenorrhea).
- •Delayed period accompanied by severe pelvic pain, high fever, or unexpected hair growth.
Emergency Warning Sign Notice🇮🇳 IN
If you are experiencing severe sudden pain, uncontrolled bleeding, high fever, or signs of Toxic Shock Syndrome (TSS), please call national emergency services (112 in India / 181 Women Helpline / 14416 Tele-MANAS) or visit the nearest hospital immediately.
Educational Health & Safety Notice
Period Talk provides general educational health information only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for personalized medical concerns.
Authority & Emergency: Aligned with evidence-based guidelines from international health organizations (ACOG, NHS, WHO, FOGSI). If you think you may be experiencing a medical emergency, seek urgent medical care or contact your local emergency service immediately.