Due Date Shmue Date
Your estimated due date maybe ingrained in your soul but does it really mean much? How likely is your baby to make an appearance at that point?
It’s so important to understand this date as it can be a real source of stress in late pregnancy, particularly if your estimated due date comes and goes.
Here are some facts about estimated due dates:
- It’s an estimation, aka an educated guess
- Less than 5% of babies are born on it, so that date being your baby’s birthday is pretty unlikely
- The methods of working out the dates out are not fool proof! Even a dating scan can be as much as 10 days out. Because let’s face it, it’s a picture of developing baby and a date is given according to its length. Who’s to say all babies would be the same length at that stage of pregnancy? Also it’s likely different sonographers would get slightly different pictures and lengths.
- Other methods of calculating the due date are based on a women’s cycle and often assume a 28 day cycle. These assumptions could make an estimated due date of a woman who doesn’t have average cycles inaccurate by a few days.
- Who says pregnancy is 40 weeks anyway? This was originally based on Aristotle’s observations that pregnancy lasted around ten moon cycles i.e 10x 28 days= 280 which is 40 weeks. This was at a time when moon cycles were a big focus and it wasn’t the most scientific way of calculating.
- Other mammals are unlikely to be given estimated due dates, perhaps we’d just trust that they’d birth when the time was right?
- Dating pregnancy at 40 weeks is not worldwide. E.g in France estimated due dates are given as 41 weeks of pregnancy.
- One in four women are still pregnant at 41 weeks.
- The World Health Organisation talks about an average pregnancy lasting 37-42 weeks, they don’t specify a particular week. Even then 10% of pregnancies do last longer than 42 weeks, where they have not opted for induction.
- Research suggests that a woman’s length of pregnancy could be affected by genetic differences and even her ethnic origin. Longer pregnancies can run in families, equally shorter pregnancies can too.
- A study in the 1990’s actually found that for first time mums they are more likely to go on average 8 days beyond their estimated due date.
- Going beyond your estimated is one of the main reasons for being offered induction of labour. Do know that this is an offering. It is your choice whether or not you accept it. You might find it useful to do your research and ask questions about it as it’s a big decision for you and your baby.
It can be so useful to be realistic about your estimated due date as early in pregnancy as possible. Perhaps focus on a due month or a period of time that your baby might make an appearance. This can help those last days/ weeks of pregnancy feel as relaxed as possible.