My pregnancy calendar

Elia' s easy-to-use pregnancy calendar lets you print out and view the weeks of your pregnancy, trimesters and key dates at a glance, as well as your due date, ultrasounds and postpartum preparations. Week by week, follow the progress of your future child.

To do so, please indicate the date of your last periodsthe average length of your menstrual cyclethe number ofchildren you have or have not had. Our pregnancy calendar will give you an exact idea of the key dates in your pregnancy.

Pregnancy generally lasts 9 months for most women, 41 weeks of amenorrhea. Three intense trimesters with their share of surprises, transformations and expectations. Between the changes in your body and the evolution of your fetus, certain dates are important to know to ensure your baby's healthy development, and medical care adapted to your needs and state of health.

Write them down now or download them from your pregnancy calendar so you'll always have them with you! 

• The date of your last periods, the date of conception or the date of transfer or insemination for those undergoing MAP;
• Expected delivery date ;
• LYour gynecologist will perform the 1st trimester ultrasound, the 2nd trimester ultrasound and the 3rd trimester ultrasound;
• Administrative: declaring your pregnancy, lregistering at the maternity ward, appointments with your midwife, calculating your maternity leave.

When your gynecologist talks to you about your pregnancy, he or she will probably talk about trimesters, weeks of amenorrhea and weeks of pregnancy. This is the difference betweenfetal age andgestational age.

Weeks of pregnancy

We speak in weeks of pregnancy when we talk about the real age of the future baby. In fact, from the date of conception to today's date. The date of conception is defined at the time of the first ultrasound scan or earlier, when the woman knows her ovulation date and the date on which she and her partner had intercourse. The pregnancy table is also easier to calculate if the mother-to-be has undergone MAP.

Weeks of amenorrhea

Gestational age is calculated in weeks of amenorrhea. Pregnancy is calculated from the date of the last periods until birth, between 38 and 42 weeks. In general, the start of pregnancy and the age of your fetus will be calculated two weeks after the start of your last menstrual period.

Calculate on the basis of the first day of periods

Calculating your pregnancy according to the first day of your periods will be reliable as long as you have a regular 28-day cycle. In fact, ovulation and the start of your last periods will be considered as the first two weeks of pregnancy. This method is therefore not 100% reliable.

To calculate her due date with the first day of the last periods, you need to add 280 days. This will give you a good estimate of your CCA.

Naegele rule

This rule is one of the most widely used for calculating your due date. To calculate your pregnancy calendar, we take into account the date of the 1st day of your last periods, the length of your cycle (between 20 and 45 days) and we add 280! On average, a cycle lasts 28 days, with ovulation occurring 14 days after the start of the cycle. If your cycle is shorter, your due date will be estimated earlier; if your cycle is longer, D-day will be later. 

Mittendorf and William's rule

The Mittendorf and William rule is more exhaustive than the Naegele rule. We luse it to create our pregnancy calendar algorithm and application. In fact, we'll be collecting more information, so the results will be more accurate. A study shows that mothers-to-be who are expecting their first child (primigravida) have a longer pregnancy. On average 288 days, compared with 283 days for those who have already had a first child (multiparous).

Our calendar will therefore be calculated by adding days of gestation to the Naegele rule.

• For primigravida: 1st day of last periods - 3 months + 15 days. An additional 8 days;
• For multiparas: 1st day of the last periods - 3 months + 10 days and 3 days more;
• This adds 8 days for primigravida and 3 days for multipara, compared with the Naegele rule.

Parikh's rule

If you have an irregular cycle, as in the case of women with polycystic ovary syndrome (PCOS), for example, the Parikh formula will be used. Indeed, the Naegele formula could give an erroneous result. The formula is: day of last periods + 9 months - 21 days + length of previous cycles.

Wood's rule

This formula takes into account the length of your usual menstrual cycles and the number of pregnancies you've already had and brought to term.

To begin, calculate your due date (DPA):

• For primigravida: 1st day of the last periods + 1 year - 2 months and two weeks;
• For multiparas: 1st day of last periods + year - 2 months and 2.5 weeks.

Then use the due date you obtained and adapt it to the length of your cycle:

• For women with a cycle of more than 28 days DPA + (actual cycle length - 28 days) = DPA ;
• For those with 28-day cycles: WFA - (28 days - actual cycle length) = WFA.

Calculate from date of conception

Even if you know the date of your last sexual encounter, the date of conception is rarely known, as spermatozoa have a maximum lifespan of 5 days, and a woman's body ovulates 24 hours after being released from the ovary.

Calculating with ultrasound

Gynecologists or midwives will perform a dating ultrasound to get an accurate estimate of the baby's age based on its development. In general, a dating ultrasound is performed between the 11th and 13th week of amenorrhea, in the absence of periods.

Calculate with transfer or insemination date - PMA

If you're undergoing ART treatment, particularly IVF, the date of conception is very easy to calculate, as it corresponds to the time of embryo transfer. This corresponds to the age of the embryo or the date of ovulation.