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20 Jan 2003

how much does the time a baby is born is determined by the month in which you conceived?how much can you rely on the midwife for estimating the due date rahther than a scan?can you explain more about the 28 days cycle and adding weeks to estimate the due date. thank you
Answer 341 views

01 Jan 0001

Angie, It’s a bit difficult for me to figure out exactly what it is that you want to know, but I’ll try to answer.
As a rule of thumb you can take the first day of your last menstruation, add 7 days and subtract 3 months to get an estimate of your due date (Nägele’s rule). This is more or less the same as taking the first day of your last menstruation and adding 40 weeks. If you have a 28 day cycle it means that you should have conceived more or less 14 days after the first day of your last menstruation. A normal baby will be delivered ate the age of 38 weeks after conception, so week add to weeks to get to the first day of your last menstruation (the date from which all estimates are made).
At the end of the day you have to remember that they’re just estimates. Only about 10% of patients deliver on the actual date, but 50% will deliver within one week and 74-88% will deliver within 2 weeks of this estimated date. Hope this answers your question. Good luck.
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