Two strips in the pregnancy test cause a wide variety of feelings in women, as both planned and unexpected pregnancies mean that women will soon begin to undergo serious changes that often turn over the habitual way of life. Some of the fair sex feel great joy, others - confusion, the third - confusion. But when the first feelings are left behind, they are replaced by questions that interest every pregnant woman. One of the first such questions is how to calculate the date of birth and determine the day the baby was born.
To determine the date of delivery, there are several methods. To date, calculate the date of delivery can every woman at any time of pregnancy.
The total duration of pregnancy is 280 days. But depending on the individual characteristics of each future mother, the baby may appear a little earlier or later than this time. Below are the main methods for calculating the date of birth.
Determination of the date of birth by conception
To calculate the expected date of birth by conception is one of the simplest methods. It is known that a woman can become pregnant only on certain days of the menstrual cycle. The greatest probability of pregnancy falls on the day of ovulation, which, as a rule, is the middle of the menstrual cycle. If the cycle is 28 days, which is the most common, then conception occurs on day 14 after the onset of menstruation. Adding to the date of conception 280 days, you can determine the approximate date of birth. This method has some error, because conception can happen a few days before ovulation or a few days after it.
Determination of the date of labor for the last menstruation
The first question that every gynecologist asks a pregnant woman is the question of the date of the last menstruation. Modern doctors use the special formula of Negele, which allows you to determine the expected date of birth on the first day of the last menstruation. The essence of the method is as follows: from the first day of the last monthly it is necessary to take three months, and add one week to the received date. For example, if the first day of the last menstruation is on August 23, then after taking three months (May 23) and adding seven days, we get the date on May 30. This method is highly accurate for women of a fair sex with a cycle length of 28 days. If the menstrual cycle is shorter or longer, the method gives an incorrect expected date of delivery.
Determination of the date of delivery with ultrasound
The ultrasound method allows you to determine the estimated date of birth with the highest accuracy, if the study was carried out at an early pregnancy - no later than 12 weeks. Up to 12 weeks, an experienced ultrasound can determine the date of conception and childbirth with an accuracy of one day. In later terms, ultrasound gives less accurate data, since the term is determined based on the size of the head of the fetus and its limbs. And since each child develops individually in the womb, the error is high.
Determination of the date of birth by first movement
The baby begins to move in the uterus about 8 weeks after conception. Mom begins to feel these movements a little later - at 18-20 weeks. To determine the expected date of birth, you need to date, when my mother first felt the stirring to add 18 weeks. This formula is valid for women who are preparing to become a mother for the first time. For re-breeding, 20 weeks should be added. This method is the most inaccurate, since its error can be several weeks. Primitive women often feel the first stirring at a period of 15 or up to 22 weeks.
Determining the date of delivery with the help of a gynecologist's examination
A gynecologist can determine the presence of pregnancy and its term by examination, but not later than at week 12. The doctor to the touch determines the size of the uterus and its shape. Based on these data, you can establish the exact length of pregnancy and the date of birth. In later terms, this method ceases to work with great accuracy, similar to ultrasound.
How do I know the exact date of birth?
None of the existing methods today allows
To date, to calculate the date of birth, you can use various calculators and tables, which, unfortunately, are also not always true. The date table of births allows you not to deal with calculations, but to determine the expected day by the date of the last menstruation or by conception.