Please help me do the math....

[Planningfor4]

Hi! I have done every kind of foreseeable research to ensure that I am educated on baking a healthy bundle of joy in the oven! The only thing I can't really figure out is regarding how to plan for a specific delivery month. It seems this would be an easy thing to do, given the ideal full-term pregnancy is 40 weeks. However, I'm having a hard time because it seems each pregnancy is determined at the date of the first missed period, which I understand makes since when you're caught off guard and need to know a due date, but I'm PLANNING to give birth in mid-late May. Why, you ask? Well, I graduate in early May, will return to school in early September, and want as much time to recover and spend with the little one as possible before classes resume. When I use pregnancy calculators, they always give me different answers... and are based on the first missed period.

Does my 40 weeks start at conception or, as some have stated, from the missed period date? If it's from the attempted conception week, that will make it much easier for me to try to plan to conceive at the right time. My Ob-Gyn is planning a c-section for me, so it's important to know, because I hope to carry the baby full-term, of course, but would like to avoid the Doc setting a date that is before the middle of May or in June.

Whaddyathink?

 

[calm]

Heh, that was very strange, as I just asked a similar question in TTC section. I have some nice answers so I will give you the link:

https://www.babyandbump.com/trying-to-conceive/267173-sorry-silly-question.html

 

[Amygdala]

If you use a due date calculator that gives you '1st missed period -> due date' just add 2 weeks. Conception last week of august should give you a mid-may baby if that helps.

 

[Whoppy-pop]

Ok I'm going to try to help without confusing you.

If you use the date of the 1st day of you last actual period (LMP= Last Menstrual Period) then this would need to be between the 25th of July and the 24th of August for you to have a baby born between the 1st and last day of May. For example if your 1st day of you actual menstrual period was the 2nd of August then your baby would be due on the 9th of May.

When you miss the 1st day of you period and get a BFP then the Dr would say that you were 4 weeks pregnant (when you have actually only been carring a baby for aprox 2 weeks) This is because your LMP was roughly 2 weeks before you "conceived" and you tested 2 weeks after you "conceived".

But obviously babies are fickle beings and generally come in their own sweet time, early or late. I hope you get a nice well behaved one x

 

[L005]

When you are planning also take into account that scheduled C-Sections are done around 38-39weeks. Not 40weeks because they do not want to chance you going into labour. So when you calculate from the first day of your last period as your start date add 38 weeks instead to determine the approx. date of your C-Section.

 

[tasha41]

40 weeks begins from the day your last period arrived.

Unless you either don't know when your last period began, have had strange bleeding, or have irregular periods, your estimated due date will be based on that date. If you had any of those issues I listed you are usually referred for an early ultrasound where they detirmine your due date. If you go for an ultrasound early in pregnancy, they are quite accurate in detirmining gestational age.

 

[silverbell]

It's 38 weeks from conception and 40 weeks from date of last period.

So scientifically you're really pregnant for 38 weeks and not 40, but you say 40 as that's what the docs go by (as most people don't know when they conceived).

Very confusing, I agree!