periods.day
Pulling out & fertile days
Understand the cycle first
Explore estimated fertile days together. No date on this calendar makes withdrawal reliable or unprotected sex risk-free.
Use period days your partner chooses to share. Lower estimated fertility is never a green light for unprotected sex.
Cycle length
Period length
Ovulation day
Period days logged: 0 days
Tap each bleeding day to add or remove it
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Enter period days with your partner’s agreement. The model highlights estimated cycle phases, not measured hormone levels.
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Hover or hold a date for context. Ovulation can move, and sperm can survive for days; lower does not mean zero.
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Discuss contraception and condoms together. A calendar cannot replace a reliable pregnancy-prevention plan or ongoing consent.
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Withdrawal can fail. Neither pulling out nor cycle tracking protects against sexually transmitted infections; condoms reduce STI risk. If unprotected sex has already happened, seek prompt advice about emergency contraception. Read about fertility awareness and withdrawal
There is no calendar date that guarantees withdrawal will prevent pregnancy. Period predictions cannot confirm ovulation, and withdrawal itself can fail. Use contraception if avoiding pregnancy matters to you.
No. Shorter or shifting cycles and sperm survival can allow pregnancy from sex during bleeding. Bleeding is not proof of a safe day.
No. Fertility-awareness methods require specific instruction and monitoring, such as temperature and cervical mucus. This app only models period dates and must not be used as contraception.
These estimates use pregnancy data from 221 women who were actively trying for a baby and had stopped using contraception. They recorded each day whether they had intercourse. Li, Wilcox and Dunson (2015, Table 3) used a statistical model to estimate the chance of a clinical pregnancy from one act on a given cycle day. This does not mean the women had sex once every day. The study did not record whether ejaculation occurred inside the vagina. These figures therefore do not estimate the risk with withdrawal. Our calendar shifts the study’s curve to match the calculated ovulation day or the cycle day you set. This is an approximation, not a validated personal prediction. Days before the table starts use its first value. The percentages are population estimates, not your personal odds or a contraceptive method. Li, Wilcox & Dunson (2015)