Safe Days Before and After Ovulation

Safe Day Birth Control Method

safe days
safe days

Safe days to avoid or delay pregnancy are in use for thousands of years. This is the oldest known birth control method used by human beings. The accuracy of the safe day’s method improves with the implementation of modern scientific knowledge. Effectiveness and accuracy of the safe day’s method are almost the same as male condoms and better than female condoms with proper use.

Many studies are favoring the proper use of safe day’s method as a birth control method. Proper use of the safe day’s method prevents unwanted pregnancy without any side effects. There are several methods of natural family planning methods are in use. The rhythm method and the mucus method are used by peoples around the world. Furthermore, they are less reliable and not standardized as a birth control method.

Birth Control App: Calculate your Safe Days

Do you have a regular menstrual cycle?

Duration of your Last Menstrual Cycle

First day of your last cycle

Safe Period Calculator: Hypothesis

Safe Period Calculator is developed to provide maximum protection against unwanted pregnancy. Basic understanding of physiological and hormonal changes of the female reproductive system during the menstrual cycle is helpful to understand the safe day calculation method.

Menstrual cycle

The menstrual cycle is commonly divided into three phases: the follicular phase (pre-ovulatory phase), ovulation, and the luteal phase (post-ovulatory phase). The length of each stage varies from woman to woman and cycle to cycle, though the average menstrual cycle is 28 days. Menstrual cycles are counted from the first day of menstrual bleeding.

The Follicular Phase

The follicular phase (proliferative phase) is the phase of the menstrual cycle before ovulation. During which follicles in the ovary mature. It ends with ovulation and the primary hormone controlling this stage is estrogen. Estrogen levels go to peaks at the end of the follicular phase. Peak level estrogen triggers luteinizing hormone (LH) and follicle stimulating hormone (FSH).


Ovulation is the process of discharges a mature ovum (egg). The time immediately surrounding ovulation is the ovulatory phase. A woman gets pregnant around the days when ovulation occurs. Usually, ovulation date is between 12 and 14 days before the first day of the next menstrual cycle.

The luteal phase

The luteal phase (or secretory phase) is the latter phase of the menstrual cycle. This stage begins with the formation of the corpus luteum, a temporary endocrine structure. Luteal phase ends in either pregnancy or degradation of the corpus luteum. The corpus luteum is needed for the production of estrogen and progesterone. The endometrium is the inner membrane of the uterus and estrogen and progesterone are required for maintaining it ready for implantation.

Infertility time frame

The infertility period depends on the life span of the sperm and the life span of the egg. The average time of ovulation is the 14th day of an average length (28 days) menstrual cycle. Ovulation time vary for every individual and can occur from 12th to 19th day of the cycle. Sperm can live up to 3 to 5 days in a woman's reproductive tract, so it is possible to become pregnant if unprotected sex occurs five days before ovulation. The life span of the typical egg is relatively short, only around 24 hours. If fertilization does not occur within that time frame, the egg will die.

How to count safe days of women after periods to avoid pregnancy

In the Safe period Method, day 1-7 of a regular menstrual period lasting from 26 to 32 days are considered as infertile or safe. Considering the 3-5 day life span of sperm cells in the female reproductive tract. Post-ovulatory infertility period calculated based on the fact; if ovulation occurs on the 19th day, fertilization can result until the 20th day of the cycle, considering the short life span of the egg. So day 21 to the rest of the cycle is considered as safe or infertile days. Since it is a calendar based method, results may vary from women to women. The World Health Organization (WHO) data shows that approximately 80% of menstrual cycles range from 26 to 32 days. Safe period calculation system reflects these data.

Natural Birth Control Recommendations

Proper use of the Safe Period Calculation method along with the withdrawal method or pull-out method is recommended as a sin-free birth control method for couples with self-control over sexuality. The withdrawal method is not recommended for adolescents or those having casual sex. Others may use condoms during unsafe days.

Who May Use the Safe Period Calculator?

  • If your average menstrual cycle length in the last six months falls between 26 and 32 days.
  • The variation between the shortest cycle and the lengthiest cycle during this time is seven days or less.

Check with your doctor about the effectiveness of natural family planning methods. The expected perfect use failure rate for this method is 3 - 4% per year.

Who Cannot Use the Safe Period Calculator?

  • If your average menstrual period length is less than 26 days or more than 32 days.
  • The variation between the shortest cycle and lengthiest cycle during the past six periods is eight days or more, you may not use this method.
  • Soon after childbirth: you must wait for six regular periods, before using this method.
  • This method is not recommended for teens and those reaching menopause.