How long does it take from conception to the birth date?
In obstetrics there are two possible calculations of the date of birth. From conception, based on a 28-day cycle, it takes an average of 38 weeks until the birth date. In this calculation, the Latin term post conceptionem is often used, which means “after conception“.
If one chooses the first day of the last period as the starting point for calculating the date of birth, which is the more common way, the pregnancy lasts on average 40 weeks, about 280 days. Here the Latin addition post menstruationem is used and means “after menstruation“. The time difference of 2 weeks between these two methods of calculation is due to the fact that with an average 28-day cycle, ovulation, and thus possible conception, takes place about 14 days after the start of the period.
A more precise calculation of the date of birth is possible with the Naegele formula. With a 28-day cycle, you add one year to the first day of your last period, subtract three months from this and add another 7 days. If the cycle lengths differ, days are added or subtracted from the 7 days according to the deviation from the 28-day cycle. If the cycle is shorter, for example 24 days long, only 3 days are added instead of 7. If the cycle is longer, for example 30 days, 9 days are added instead of the 7.
Is it possible to calculate the sex of the child by calculating the day of conception?
There have always been many couples who prefer a certain sex for their offspring when planning their family and who want to take appropriate steps to conceive. For this reason, numerous alleged methods and supportive behaviors can be found in literature and on the Internet, which are supposed to allow an alleged influence in sex determination. It is a fact that the amount of data and studies that can be taken seriously in medical terms is extremely small.
Therefore, when using special formulas or moon tables, it should always be kept in mind that the desired sex is not guaranteed in any way. An often mediated calculation of the sex is based on the assumption that girls are more likely to be conceived in the days just before ovulation, whereas the probability of conceiving a boy should be highest on the day of ovulation itself. In addition, the Chinese lunar calendar is often used to calculate sex. The age of the mother and the month of conception should play a role here. The alleged sex of the child can then be read off in the form of a table.