Pregnancy Due Date Calculator

How do you want to calculate your due date? First day of my last period Conception Date Date of Ultrasound IVF Transfer Day Advanced Method First day of my last period Date I conceived (Projected) Due Date Date of Ultrasound IVF Date Advanced Method The advanced method uses the Mittendorf-Williams rule, which is said to be more accurate since it takes more factors into account like race, weight and coffee consumption. Average Length of Cycle 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 days (default 28) Average Luteal Phase Length 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 days (default 14) Gestational Age 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 31 32 33 34 35 36 37 38 39 40 weeks 0 1 2 3 4 5 6 days IVF 3 Day Transfer Date

IVF 5 Day Transfer Date

Egg Retrieval Date Maternal age 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 Race Caucasian Non-Caucasian Pre-pregnancy height ft in cm switch to metric Pre-pregnancy weight lbs kg Higher education No Yes Alcohol during pregnancy No Yes Cups of coffee per day 0 1 2 3 4 5 6 7 8 9 10 11 12 Incompetent cervix No Yes First pregnancy No Yes DES exposure in cervix No Yes History of miscarriage No Yes History of stillbirth No Yes Bleeding None 1st Trimester 1st & Other 2nd, 3rd or Both Placenta previa No Yes Placental abruption No Yes Premature rupture of membranes No Yes Pregnancy induced hypertension No Yes

How is my due date calculated?

Your due date is calculated by adding 280 days (40 weeks) to the first day of your last menstrual period (assuming a 28 day cycle).

Note that your menstrual period and ovulation are counted as the first two weeks of pregnancy. If you deliver on your due date, your baby is actually only 38 weeks old, not 40.

Your due date is only an estimate

Please remember that your due date is only an estimate. Every pregnancy is unique and your baby will come when it's ready. Be sure to talk to your health care provider about your due date.

On average only 5% of births take place exactly on the estimated due date. Most are born within a week either side of the estimated due date. A normal pregnancy can last anywhere between 38 and 42 weeks.

Each due date report contains the following data:

Estimated Due date

Conception Date

Baby Status (Size, Weight, Heartbeat)

Due Dates for Multiples (Twins, Triplets, Quads)

Trimester Stages

Prenatal Testing Dates

Timeline of Significant Milestones in Embryo/Fetal Development

Imagine, Your Baby Will...

Fun Due Date Facts

Famous People Born on The Due Day

The Due Day In History

If you want to, you can view a sample due date report.

Pregnancy Calendar

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