When you know you’re pregnant one of the first thoughts may be about the baby’s birth date. You’ll probably want to know how to calculate your due date even before you make an appointment to see a medical doctor. There are several ways to calculate the due date but all of them are estimates. Unless your delivery will be a scheduled c-section and sometimes, even in spite of that schedule, the baby will make his or her decision on when to be born, no matter what the due date calculation says.
Once you have estimated your due date and start to get used to the idea of being pregnant, it may surprise you to find out you are further along in the week count than you thought. While you may know exactly when the baby was conceived, the weeks of a pregnancy and the trimesters are commonly estimated based on the start of your last period. This means the first two weeks in the first trimester actually took place before you were even pregnant.http://www.mayoclinic.com/health/prenatal-care/PR00112
Due Date Calculating Information
Calculating the due date is simple. Begin with the first day of the last menstrual cycle. Add nine months to this date and then add seven more. This simple method of estimating due date is useful when the last cycle start date is known.
Step 1: Calculate from Conception or Ovulation
Average time for pregnancy from the time of conception is 38 weeks. Most people do not know the conception date but if this date is a known fact it can be used to predict the due date. When using the conception date, 38 weeks or 266 days can be added to the date to estimate the time the baby will arrive. If you have been tracking ovulation with a prediction kit or by monitoring basal body temperature, you may use this known date for projecting your due date.http://www.tubal-reversal.net/pregnancy-due-date.php
Step 2: Early Dating Scan
An early dating scan is an ultrasound which is used to estimate the due date when the date of the last menstrual period is unknown. This may be necessary if your cycles were not regular before becoming pregnant. Early dating scans are believed to be reliable within a 10 day window of time meaning the delivery may be 10 days before or after the date established by the scan. The ultrasound is done between 12 and 22 weeks for the best projection of due date. After 22 weeks the size does not project due date as accurately.http://www.ultrasoundcare.com.au/services/pregnancy-ultrasound-5-17-weeks-dating-and-viability.html
Step 3: Naegele's rule
Franz Karl Naegele, a German obstetrician, was the first to standardize how to determine due date for pregnancy. His method which has become known as Naegele's rule was published in 1830. This rule says the due date is estimated by taking the first day of the last menstrual cycle, add one year, subtract three months, and then add seven days to that date. The rule does not take into consideration the varying lengths of menstrual cycles but still forms the initial basis of due date calculation. Ultrasounds have been used for more accurate estimates since the 1970s.http://www.livestrong.com/article/248211-how-do-i-determine-a-babys-due-date/#ixzz11sHbC1VH
Other Mahalo Pregnancy How-To Pages
You may be interested in these Mahalo How-to pages related to pregnancy:
- How to Get Pregnant
- How to Get Pregnant Fast
- How to Get Pregnant Videos
- How to Improve Male Fertility
- What Are Pregnancy Trimesters
- How to Monitor Your Fertility Cycle
- How to Chart Your Basal Body Temperature
- How to Improve Fertility
- How to Calculate Ovulation
- How to Find a Fertility Specialist
- How to Monitor Your Fertility Cycle
- How to Choose a Fertility Doctor
- How to Find a Gynecologist
- How to Induce Labor
- How to Induce Labor Naturally
How to Chart Your Basal Body Temperature
Dr. Michael C. Lu of the UCLA Department of Obstetrics and Gynecology and author of Get Ready to Get Pregnant discusses how to chart your basal body temperature. He recommends a tracking system, supplies needed, the methods needed to accurately take the temperature and how to chart the temperature. He also recommends charting cervical mucus changes.
How to Eat Healthy During Pregnancy
The author of "Get Ready to Get Pregnant: Your Complete Prepregnancy Guide to Making a Smart and Healthy Baby," Dr. Michael Lu, MD MPH, of UCLA, gives his take on how a woman should eat before and during pregnancy.
How to Make Sex Productive to Get Pregnant
This video features an obstetrician named Michael Lu, and here he offers some advice regarding sex and pregnancy. He claims that the egg is only available for fertilization for a 24 hour window, and thus the key is to have sex at this time. This is why he recommends learning when you are ovulating so that you can have sex.
How Much Weight is Gained During Pregnancy
Dr. Michael C. Lu, author of Get Ready to Get Pregnant and a professor and director at the the UCLA Department of Obstetrics and Gynecology discusses weight gain and pregnancy. He reviews the general recommended weight gain guidelines as well as pre-pregnancy tips for minimizing excessive weight gain. He recommends a balance of diet and exercise as well as minimizing stress to help balance pregnancy weight gain.
Disclaimer
The content in this page is not a substitute for professional medical advice. Please contact your doctor before using the information presented here
References
Fast Facts
-
Online calculators
Websites offer calculators based on last menstrual period
-
Franz Karl Naegele
Developed first method of estimating due date
-
Conception date
Can be used for determining due date if known
