Here, we’ll review 5 fertility facts every woman needs to know—whether she is trying to conceive or not.

1. You’re only fertile 6 days per month
   The truth is: you can only conceive six days per cycle. Only six! That means you’re fertile for about 20 percent of each month. So, if you’re trying to conceive, 80 percent of the time is waiting until you can try again. This is why tracking your cycle can be extremely valuable, as it will shed light on when you ovulate.
2. You can conceive after age 35
   You might have heard of a myth out there called the “fertility cliff.” The idea (based on a study that happened in the 1600s, yes, you read that right!) is that after age 35 your fertility falls precipitously. But the fertility cliff is false. While your fertility does decline with age—it happens gradually over time. The reason is that at birth, women have a finite number of eggs (or oocytes) in their ovaries. And with age, both the quantity and quality of those eggs declines gradually.
3. Your cycle is variable
   Remember your 6 fertile days? Well, they can be tricky to find: Your body doesn’t follow a Swiss train schedule. Your cycle is variable and your fertile days (those 6 days each month that you can conceive) don’t follow a schedule. Again, this points out how cycle tracking can help you pinpoint your fertile window.
4. You are more fertile on some days than others
   You are more likely to get pregnant on some of those 6 fertile days than on others. In fact, according to research, here are your most fertile days, ranked in order:

Sex on one, two, or three days before ovulation = 20–30% chance of getting pregnant
Sex four days before ovulation = 10–12% chance of getting pregnant
Sex five or six days before ovulation = 0–5% chance of getting pregnant

1. Sexual positions don’t affect your chances of conception
   One question that couples often wonder about when trying to conceive is whether or not certain positions during or after sex can increase the likelihood of getting pregnant. Pretty much as long as male ejaculates during sex, and sperm goes into the vagina, positions during or after sex don’t affect odds of conceiving.