ELI5: Explain Like I'm 5

Calendar-based contraceptive methods

Okay little one, let’s talk about something called ‘calendar-based contraceptive methods’. This is a way that some people use to prevent pregnancy.

Imagine your mommy has a calendar at home. It has 12 big squares, one for each month. Each square has smaller squares inside it for each day of the month. Your mommy can use this calendar to see when she is more likely to get pregnant if she has sex.

When a mommy has monthly periods, it means her body is getting ready to have a baby. Every month, one of mommy's ovaries releases an egg, which can be fertilized if a sperm meets it. But the egg only lasts for about 24 hours.

Calendars can help mommy figure out when she is most likely to get pregnant based on when she has her periods. This is because the time she is most likely to get pregnant is when the egg is released and travels through the fallopian tubes towards the uterus. This is called the ‘fertile window’. This means that if mommy has sex during this time, there is a higher chance that she could get pregnant.

The calendar method can help mommy figure out when her fertile window is. To do this, she tracks the length of her monthly periods over a few months to work out the average number of days she has between each period. Then she uses that number and the first day of her last period to work out when the next period is due. Based on this, she can work out the best days for her to have sex and avoid having sex during the days she's most likely to get pregnant.

It’s important to remember that the calendar method is not the most reliable form of birth control as it can be influenced by many factors like stress, changes in weight and other medical conditions. So, your mommy should always talk to a doctor if she wants to use the calendar method as her primary form of contraception.