How to Calculate Your Due Date:
Annalise has been feeling lethargic of late and she recently threw up for no apparent reason. This isn’t a good sign and she eventually manages to make time to go to the hospital. She’s thinking malaria or a stomach bug of some kind and the latter wouldn’t be a surprise because she’s been too busy to eat right and fast food can get to you.
At the hospital the doctor runs some tests and finally gives her a hearty congratulation. She wonders why anyone, let alone a doctor, would congratulate another on being sick. Weird fellow! Noticing the puzzled look on her face the doctor tells her the news. She’s pregnant! Pregnant and sick is a bad combination, she says out loud. The doctor says that she’s feeling sick because of the pregnancy and that she has no illness at all. It takes time to sink in and she walks home dumbfounded. She finally absorbs the news and goes back to hospital a few days later to find out when this baby will be coming (never mind that it’s a clump of cells at this point) because she can feel it’s going to be soon.
Many women get to this point and the doctor asks several questions to help them figure out when the baby will be coming.
The doctor will ask when your last period started (first day of the last monthly period). She will also need to find out whether you have a regular cycle. This will help determine what method to use to determine your due date. With a regular cycle it is easier to calculate. Doctors usually take the date you gave as being the first day of your last period and then count three months back. Once that is done they add seven days to the date and you have an approximate date for your delivery.
It is important to note that this date is merely an estimate and could change. One should therefore use it as a guideline and shouldn’t expect that it is set in stone. Studies actually show that only 1 in 20 babies actually get born on the given EDD. Doctors usually say plus or minus two weeks of the EDD is well within range which means that most babies actually get born between 38 and 42 weeks. This is because they count your period plus ovulation as the first two weeks of the pregnancy.
Other ways to determine the due date
Thankfully there are other ways to figure out when to expect the baby. This comes as a relief for those with irregular cycles because they can never really tell when they are ovulating.
- The size of the uterus gives clues as to how big the baby is and therefore its age. It is usually measured during the first internal pregnancy examination.
- The fundal height which is the top of your uterus. As the baby grows the uterus also expands and is expected to reach your navel around week 20. Once it gets here the doctor automatically knows how far along you could be and therefore when to expect the baby.
- An early ultrasound can give more accurate dates. Many women however, don’t do early ultrasounds unless the doctor recommends it. Some doctors only recommend it in cases where the cycle is irregular while others do it regularly, with or without special circumstances.
- Some pregnancy milestones will give a doctor a clue as to how far along the pregnancy is. The first fetal movement, for example, occurs at between 16 and 22 weeks.
Sometimes these dates are just off and the EDD ends up changing along the way but that’s nothing to worry about. One can do their own calculations using the pregnancy due date calculator just to be on the safe side.
As you go ahead to determine your EDD remember to start your doctor’s visits, to take prenatal vitamins and to eat a healthy and balanced diet throughout your pregnancy.