How to calculate your pregnancy

2024 Author: Malcolm Clapton | [email protected]. Last modified: 2023-12-17 03:44

The best way to cope with this task is a doctor.

Determining the exact duration of pregnancy is not an easy task. It is not enough to know when the momentous intercourse took place. In order not to be mistaken, you need to be aware of the monthly cycle of the expectant mother, as well as take into account dozens of other factors, for example, the size of the uterus and embryo.

The most reliable way is to contact a gynecologist, answer his questions, undergo a physical examination and do an ultrasound scan Methods for Estimating the Due Date. Based on the results of the examination, you will be told how long you are pregnant.

However, you can more or less accurately estimate what week you are on your own. But for this you need to know some of the nuances.

Why confusion arises with the timing of pregnancy

Suppose you firmly know that conception took place only two weeks ago and not a day earlier. However, the doctor to whom you contacted about the delay in menstruation, after an ultrasound scan and other measures, puts a different gestational age - 4–5 weeks. Who is right? In general, both sides. But the gynecologist is still more to the right.

Many pregnant women face this confusion.

The fact is that the expectant mother is trying to calculate the gestational age in real, so-called embryonic weeks. And the gynecologist - in obstetric. The difference between them is approximately 14 days. How Your Fetus Grows During Pregnancy.

Obstetric weeks are considered to be the most accurate method for measuring pregnancy. And there are good reasons for that.

What are fetal weeks and why are they inaccurate

In embryonic weeks, the real age of the fetus is counted - that is, the period that has passed since the moment of conception. At first glance, this looks like the most logical option for determining the gestational age. But there are two problems.

1. The day of sexual intercourse cannot serve as a starting point

Fertilization occurs only during ovulation - a short, about a day, period when the egg leaves the ovary. If at this time she meets with sperm, conception will occur. If not, you will have to wait for the next cycle.

With a 28-day cycle, ovulation is believed to occur on day 14. However, the dates float: the egg can leave the ovary a few days earlier, and a couple of days later than the estimated date.

Sperm, in turn, are able to wait for the egg in the fallopian tube for 3-4 days. This means that fertilization does not take place at the time of intercourse, but sometimes only a few days later.

2. Pregnancy does not occur at the time of fertilization of the egg by the sperm

Conception occurs only when a fertilized egg is implanted into the wall of the uterus. This, by the way, does not always happen. If a woman takes oral contraceptives or, for example, something is wrong with the embryo, she will not get pregnant.

Egg implantation, that is, the immediate start of pregnancy, occurs 6–12 Early Pregnancy Symptoms days after fertilization.

Therefore, it is impossible to accurately determine the physical duration of pregnancy and the embryonic age of the fetus. To avoid inaccuracies, the term is calculated in obstetric weeks.

How obstetric weeks are calculated

They are counted not from the moment of conception, but from the first day of the last menstruation. As a rule, all women know this date for sure, so mistakes are almost excluded.

The obstetric period of pregnancy is on average 14 days longer than what a woman considers real.

This difference is equal to the average period between the first day of menstruation and the expected ovulation.

Why you need to count obstetric weeks

Firstly, each of them is associated with one or another important stage in the development of the future baby.

Secondly, the date of onset of menstruation is closely related not only to ovulation, but also to the estimated due date (PDD). To calculate the PDD, gynecologists use the so-called Calculating a Due Date rule, according to which exactly 40 obstetric weeks or 280 days pass between the first day of menstruation and childbirth.

The calculation according to the Negele rule takes place in three stages.

1. The first day of the last menstrual cycle is determined.
2. Exactly three calendar months are subtracted from this date.
3. The year and 7 days are added to the received date.

For example, a woman's last menstrual period began on November 9, 2019. If you subtract 3 calendar months, it will be released on August 9, 2019. We add a year and 7 days and we get August 16, 2020. This date will be the estimated due date.

How to calculate your pregnancy

It's simple. Mark the start date of your last period on your calendar and count how many weeks have passed since then.

If, for example, your last period started on June 6, and today is July 18, your pregnancy is 6 weeks.

What apps will help you calculate your pregnancy

To avoid having to re-calculate the weeks each time, you can use mobile organizer apps. It is enough to enter the date of the first day of the last menstruation once - and the program will automatically calculate which obstetric week you are in. At the same time, she will help you keep track of your well-being, remind you of the need for planned visits to the doctor, and provide information about the development of your baby.

1. Pregnancy calendar

The application helps to accurately calculate and track the obstetric gestational age, and also determines the expected due date. In addition, it tells about how the child is growing, what happens to him on each particular week. This information is presented in simple and visual ways: for example, the weight of the baby is compared with the mass of popular vegetables and fruits.

The condition of the mother is monitored separately. At the start, the application will ask you to indicate your individual characteristics - age, height, weight. Based on these data, the program calculates the optimal weight gain and gives recommendations on how to take care of yourself, what to eat and what exercises to do.

2. Pregnancy Tracker

This utility was created by BabyCenter, the world's largest online resource for motherhood and childhood. The leading doctors of the best American clinics act as consultants.

In the application, you can not only calculate the obstetric gestational age and the expected date of birth, but also get expert information on how the baby is developing day by day. The mom-to-be will receive advice on nutrition, vitamins, exercise, and weekly checklists to remind you to visit your gynecologist or get routine tests.

The only drawback of the application is that it is in English.

3. Mom Life

Another simple application that helps to calculate the duration of pregnancy and the date of the upcoming birth, and also gives the expectant mother complete information about what is happening to her and the baby every week.

The trick of this utility is social contacts. By providing Mom Life with your location, you will be able to find women of the same gestational age who live near you. Also available in the application are reviews of doctors, clinics, maternity hospitals located nearby.

There is also a worldwide chat where you can communicate with mothers from different countries and, if necessary, receive advice and support from them.