Conception is the time when sperm travels up through the vagina, into the uterus, and fertilizes an egg found in the fallopian tube. Conception — and ultimately, pregnancy — can involve a surprisingly complicated series of steps. Everything must fall into place for a pregnancy to be carried to term.
The date of conception is the day on which a person's baby is conceived.
Conception occurs when a sperm cell from a fertile man swims up through the vagina and into the uterus of a woman and joins with the woman's egg cell as it travels down one of the fallopian tubes from the ovary to the uterus.
Conception (when the egg is fertilized by the sperm) can take place as soon as three minutes after sex or it may take up to five days. Implantation (when the fertilized egg attaches to the uterine wall) occurs five to 10 days after fertilization—which means it can happen anywhere from five to 15 days after you had sex.
To find your conception date, you will have to perform some calculations to estimate it. Find out on what day your last period began, and add your average cycle length in days to that date. Finally, subtract 14 days and you will have an estimate of conception date.
You're most fertile at the time of ovulation (when an egg is released from your ovaries), which usually occurs 12 to 14 days before your next period starts. This is the time of the month when you're most likely to get pregnant. It's unlikely that you'll get pregnant just after your period, although it can happen.
Is it possible? Although it is possible to get pregnant in the days leading up to your period, it isn't likely. You can only get pregnant during a narrow window of five to six days a month. When these fertile days actually occur depends on when you ovulate, or release an egg from your ovary.
Can I get pregnant just before my period? The probability of conceiving if you have sex two or three days before your period is extremely low. Since your egg lives for around 12 to 24 hours after it is released, this means your fertility window closes soon after you ovulate.
The researchers found that the probability of a person getting pregnant rises sharply 7 days after the LMP. This probability of pregnancy is highest at 15 days and returns to zero by 25 days. For the women in the study, the probability of being within the fertile window was: 2 percent at day 4 of their cycle.