DUE DATE CALCULATOR WEEK BY WEEK HOW TO

During the first and second weeks of the first trimester, the egg released by the female will be fertilized by the sperms that enter the uterus following unprotected vaginal sex.The first trimester is called early pregnancy that lasts from the 1st to 13th week. Note that due dates are not expiration dates! Most first-time moms will give birth 3 to 5 days past their due date, and a great many go longer than that still.A full-term pregnancy of 40 weeks is divided into three trimesters with each trimester consisting of three months in duration. In fact, only about 4% of women will give birth on their due date. In short, due dates are not very accurate. Related: 9 essential questions to ask during your first prenatal visit How accurate are due dates? Surprisingly, as your pregnancy progresses, it becomes harder to calculate the gestational age and size of the fetus with an ultrasound (the bigger they get, the more inaccurate the measurements are). The ultrasound technician will measure the size of the embryo and use the information gathered to determine your due date. A history of irregular periods, medications and plain ol' forgetting are all normal reasons to be unsure.Ī transvaginal ultrasound (where a lubricated ultrasound wand is inserted into the vagina) can help pinpoint your estimated due date, especially when done in the first trimester. Related: September is by far the most popular birthday month-and here’s why Using ultrasounds to determine your due dateįor a variety of reasons, a lot of women don't know when their last period was (so don't worry if you're not sure, mama). You can also use a due date calculator, which can help if you know the day of intercourse, insemination or embryo transfer, or try our handy graphic below. Subtracting three months from April brings you to January.Write down the first day of your last LMP.Your due date is based on the first day of your last menstrual period (LMP). There are a few ways to calculate your due date. At 42 weeks, the pregnancy is considered post-term.At 41 weeks, the pregnancy is considered late-term.At 37 weeks, the pregnancy is considered early-term (technically full-term, but on the early side of it).

Delivery prior to 37 weeks is considered preterm. Your pregnancy is considered full-term after 37 weeks. Pregnancies last approximately 280 days, which is 40 weeks, or about 10 months-not nine like we traditionally hear. Related: The new mama's guide to pregnancy symptoms How long is pregnancy? Whatever phrasing you use, your due date is the day that we estimate your baby will be born.

Estimated date of confinement (EDC) (Wait, what? Back in the day, women were confined to a bed or hospital when they gave birth, hence the word confinement.).

Try our due date calculator below! What is a due date?ĭue dates can encompass a range of terminologies, all referring to the same thing.

DUE DATE CALCULATOR WEEK BY WEEK HOW TO

Let's discuss what due dates are, and most importantly, how to determine when your due date is.

If that's the case, your doctor or midwife will likely recommend what's known as a dating ultrasound to help determine how far along you are. From there, we can estimate the due date based on a simple mathematical equation (more on that below).īut what if you don't remember the first day of your last period? Or what if you are someone who doesn't get regular periods? No problem.Īs I share in The Motherly Guide to Becoming Mama, it's common for women not to know when their LMP was. When trying to calculate your due date, your medical team will often start with your last menstrual period, or LMP (the first day of your last period, to be exact). Whether you are trying to conceive with specific timing in mind, or are already pregnant and curious to know when your little bundle will arrive, thinking about due dates is exciting-and gives you a thrilling countdown. Pretty much every mama out there has found themselves searching the internet for a due date calculator.

Due date calculator week by week