How to calculate your pregnancy in weeks and months.
Your bundle of joy is on the way and we are so happy for you!
Lots of women make mistake when asked how old their pregnancy is or how far along they are. You hear people say “I am 2 weeks pregnant”. This is not correct. So we will be using this first post to help you understand how exactly pregnancy weeks and months are counted.
It is true that the actual day you conceived is the day you ovulated and the sperm reached the egg and they fused together – which is probably 2 weeks after the first day of your last menstruation. But because no one is actual so sure of what day exactly this happened, medical practitioners ask you the date of the start of your last menstruation and they count this day as the 1st day of your pregnancy (because that is the day they are certain of)
This way, by the time you miss your period, you are already 1 month pregnant (even though, technically, its 2 weeks after your ovulation and therefore 2 weeks after you conceived).
So there is no such thing as being 2 weeks or 3 weeks pregnant. From the day you missed your period and are certified to be pregnant, you are already at least, 4 weeks pregnant.
Pregnancy is estimated to last nine calendar months and seven days, or 40 weeks. So you start calculating this length of time from the first day of your LMP (Last Menstrual Period) to get an idea of when your baby will be born.
The due-date calculation works best if your menstrual cycle is regular and your periods are every 28 days.
If you have an irregular menstrual cycle, or you don’t know the date of your LMP. And if your cycle varies in length, counting from the first day of your LMP may not give you a date you can rely on.
Don’t fret! Your first ultrasound scan, will give you a more accurate due date for your baby. This is calculated by measuring your baby’s length from his head to his bottom. This is called his crown rump length. You should be sent for your 1st scan when you are between 10 weeks and 13 weeks