Not all women know the best time for pregnancy. And yes, there are times that are usually much more successful than others. Every woman has her own reproduction cycle, not every woman is the same. But for most women, two weeks before the next menstrual period, ovulation (the highest chance of sperm) occurs.
If you have a generally 28-day cycle then it means that Day 14 will be the most productive. Some women have cycles that do not fit into the "normal" range, so if your cycle is usually 36 days, you will have the highest odds on day 22 of the cycle.
If you have no idea what your cycle is, you can go to the store and you can hire a cheap ovulation kit, help you determine what your cycle is, and when the best time to be pregnant. Most tests will inform you about 24 to 48 hours before the ovulation begins, so there is plenty of time to prepare.
By charting BBT (Basal Body Temperature), you have a better chance of seeing yourself ovulating exactly. Usually, the temperature will remain about 1/10 at "normal" temperature, but if it is about 6/10 degrees higher than usual for a few consecutive days, this is a good sign, Ovulating.
If we find out that your pregnancy is the best time for your body, you will be able to set yourself up. Take the stress out of trying to get pregnant by using methods that worked for millions of millions.