Fertilization can only happen if a sperm and an egg meet. Once it's released from the ovary, an egg can only live for about 12 to 24 hours. Sperm, on the other hand, can live for 3 to 5 days inside your body. There is a window of time known as the “fertile window” where pregnancy is possible during each month.
The egg lives for approximately 24 hours in the reproductive tract. On the other hand, sperm can live for up to five days under the right conditions. This means that most people can conceive for about six days during each menstrual cycle—the five days before ovulation and one day afterwards.
Once the sperm have entered the uterus, contractions propel the sperm upward into the fallopian tubes. The first sperm enter the tubes minutes after ejaculation. The first sperm, however, are likely not the fertilizing sperm. Motile sperm can survive in the female reproductive tract for up to five days.
Sperm would have a 5% probability of surviving more than 4.4 days and a 1% probability of surviving more than 6.8 days.
Ejaculated sperm remain viable for several days within the female reproductive tract. Fertilization is possible as long as the sperm remain alive — up to five days. Sperm can also be preserved for decades when semen is frozen.
You are most likely to conceive during the 5 days before ovulation, along with the day you ovulate. Sperm can live up to 5 days inside your body, so if you have sex up to 5 days before your egg is released, you can get pregnant. After ovulation, your egg can only live for 12 to 24 hours.
From studies over a threeyear period among 44 women, they find that sperm cells can stay alive or active in the female for as long as seven days.
But because sperm can live for three to five days in the reproductive tract, it's also possible to get pregnant by having sex in the five days leading up to ovulation. (In other words, five-day-old sperm can still fertilize a newly released egg.)
Since sperm can only live for a maximum of 5 days in the female reproductive tract, only a small number of sperm will even survive the long journey through the female reproductive tract. Therefore, couples trying to conceive should plan to have intercourse a number of times in the days just prior to ovulation.
The World Health Organization (WHO) recommends that for testing and analysis, semen samples should be collected after a minimum of 2 days and a maximum of 7 days of sexual abstinence [1].
There is ample evidence to show that as millions of human sperm cells swim towards a waiting ovum or egg, only one gets to fertilize it.
The cervical entrance (os) is not only very small, but it is blocked by cervical mucus. During most times in the menstrual cycle, cervical mucus is highly sticky (G mucus) and represents an almost impenetrable barrier to sperm penetration.
Scientists discovered that there was pretty much no difference in the odds of getting pregnant between the group that got up and moved around and the one that went on short bed rest.
After ovulation the egg lives for 12 to 24 hours and must be fertilised in that time if a woman is to become pregnant.
A person can conceive at any time, but especially if they have sex from 5 days before until 1 day after ovulation. Ovulation occurs when one of the ovaries releases a mature egg. This is the time when the body is ready to receive sperm for fertilization.
Ovulation usually occurs about two weeks after your menstrual period and lasts for two or three days. This means you can sometimes determine when you conceived based on your ovulation cycles — simply determine when your last menstrual period was and add approximately two weeks.
What are the chances? Having sex as close as possible to the time of ovulation increases the chance of pregnancy. If a woman has sex six or more days before she ovulates, the chance she will get pregnant is virtually zero. If she has sex five days before she ovulates, her probability of pregnancy is about 10 percent.
A healthy sperm can live from a couple of hours to as long as five days after intercourse.
This is because sperm can live for around 5 days inside a woman's body, so if you've had sex in the days before ovulation, the sperm can 'wait' for the egg to be released. These days before and just after the egg is released is often called the 'fertile window'.
So, can you get pregnant when you're not ovulating? The short answer is yes. It's possible to get pregnant outside of your predicted fertile window because timing of ovulation may differ each month and sperm lives in the body for several days.
Ideally, you want to have sperm ready and waiting for the egg.
"As we were expecting, the sperm from the first fraction of ejaculate were faster moving and the count was higher, and more importantly, they had higher DNA integrity than sperm from the second phase," says the researcher.