Conception & Due Date

Wondering when you conceived, or when you could be due? Our Due Date Calculator can help. Simply input the required information below and get an estimate for your conception and due dates immediately. If you need more information or you have questions about pregnancy, parenting, or your options, call Calaveras Door of Hope Pregnancy Resource Center at (209) 736-9600.

Due Date Calculator

Please select the first day of you last period

You last period date:

How to Estimate Your Conception Date

The simplest way to estimate your conception date is to count forward approximately two weeks from the start of your last menstrual period. Most women ovulate two weeks after their period ends, and ovulation is when you are most fertile and most likely to become pregnant.

You can also get a much more accurate estimate of your conception and due dates with an ultrasound. Ultrasounds are simple, painless medical procedures offered at doctor’s offices, OB/GYN clinics, and other medical providers.

Menstrual Cycle

To estimate your conception date based on your menstrual cycle, simply add approximately two weeks from the first day of the last menstrual period you had before you became pregnant. This should give you the start of your ovulation period, when your body is most fertile and likely to become pregnant. Ovulation is a normal part of a woman’s monthly cycle, and it usually happens about two weeks after your menstrual period ends.

Keep in mind that this method isn’t 100% accurate. It is possible to become pregnant at any time during the month, not just during your ovulation period. You can even become pregnant during your menstrual period. Also, remember that these estimates are based on the average woman’s regular 28-day menstrual cycle. If your cycles are irregular, this method may not work for you.

You should also know that a man’s sperm can stay alive inside your uterus and fallopian tubes for several days after intercourse. In other words, you might not actually conceive until days after having intercourse.

Limited Ultrasound

In contrast to menstrual cycle estimation, ultrasounds are much more accurate at estimating your conception date. This is because an ultrasound can directly observe your baby’s development and estimate its age. Ultrasounds can also determine whether your pregnancy is healthy and viable.

Calaveras Door of Hope can provide you with a referral to get an ultrasound at a doctor’s office or clinic nearby. Call us today for more information.

Date of My Last Period?

If you aren’t sure when your last period was, or your periods are not very regular, it will be harder to determine your conception date and due date using a pregnancy calculator. Your best option in this case is to get an ultrasound to see how far along your pregnancy is, along with an estimate of your conception and due dates.

Free Pregnancy Test

If you’re not sure if you’re pregnant, not sure how far along you are, or have other questions about pregnancy and your options, call or visit Calaveras Door of Hope Pregnancy Resource Center. Call (209) 736-9600 to schedule your appointment or walk in during our office hours. All services are free and confidential.

Pregnant? Need Help?

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