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Home Did You Know: Japan Did You Know: Pregnancy in Japan

Did You Know: Pregnancy in Japan

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Did you know that rather than the 9 months it takes western women to give birth after conception, it takes Japanese women 10 months.

Why would this be? Is it due to a difference in body temperature? Is it because of body size? or is it that Japanese babies take longer to mature in the womb?

Well, you may be surprised to heard that, actually iit is none of the above. There are two theories why the Japanese will often say that from conception to birth takes ten months.

The first is the way the months are counted. The time from conception is 40 weeks. That's nine months, right? Well it is if you count calendar months, but in Japan, for some reason, pregnancy months are counted as four weeks. This means that although the pregnancy lasts for 40 weeks, it counts as 10 months due to the 4 week month rule.

Another possibility lies in the way the date of conception is arrived at. In western countries, doctors count from the period that would have followed the conception (this is, of course, hypothetical). Japanese doctors, on the other hand, count from the last cycle (ie the one before the estimated time of conception). This difference therefore gives us the one-month descrepency.

Whichever counting system is used, women, both in the west and in Japan, have a pregnancy lasing approximately 40 weeks.


How long does it take in your country?



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Comments (1)
1 Thursday, 10 November 2011 03:57
this was puzzling me as a Japanese visitor to my house yesterday was asking how long our pregnancy with my son had been and when I told him nine months, he told me Japanese pregnancies last ten months and we were both very puzzled by this.

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