"How pregnant am I?"

It's hard to predict a baby's exact arrival date, but this calculator can help give you an idea.

To calculate how pregnant you are, just enter the first day of your last period. If you don't know the exact date, you can simply estimate it as closely as possible. And, again, please keep in mind that the information provided by this calculator is an estimate based on your last menstrual period.

Please enter the first day of your last menstrual period:
January February March April May June July August September October November December   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30   2006 2007 2008 2009 2010
Based on your LMP, today you are week(s) and day(s) pregnant.
Conception likely occurred around: (Approximately two weeks after your last menstrual period)
Estimated due date (40 weeks - full term): Note: Your due date cannot be perfectly predicted, even if the exact date you concieved is known. Calculating your due date based on the first day of your last menstrual period (LMP) is the method used universally by medical professionals to determine your Estimated Date of Conception (EDC), but there are also other factors involved. To determine your correct due date, you should always consult your doctor.
Other Notable Milestones
Reliable positive pregnancy test:	(5 weeks)
Beginning of organ formation:	(5 weeks)
Major organs have formed:	(10 weeks)
End of first trimester:	(12 weeks)
End of second trimester:	(27 weeks)

As soon as you think you're pregnant, it's important that you contact your physician or other health care professional immediately.

General Information
Medically, an average human pregnancy lasts for about 280 days or 40 weeks from the date of the last menstrual period (LMP). 40 weeks is the best average length of pregnancy. Since the number of weeks in a month varies, knowing how many weeks pregnant you are is much more accurate than knowing how many months.

Please keep in mind that you may not have conceived on the exact day that you had intercourse. Sperm can survive in the uterus for up to 3 days. LMP is the best constant from which to measure probable date of conception. Fertilization occurs -- generally -- around 14 days after the start of your last period.