By sumanOn

HOW TO DO CALCULATION OF EDD, OBSTETRICAL SCORE AND GESTATIONAL WEEKS

By the end of this exercise, the participant will be able to calculate the Expected Date of Delivery (EDD), Gestational weeks and Obstetrical score for an antenatal mother as a part of an antenatal assessment and examination.

Estimating pregnancy dates is important for both the mother, who wants to know when her baby will be born, and her health care providers, who can choose when to perform various screening tests and assessments, such as serum screening, maturity assessment, and induction of labour for postdate pregnancies.

Participants can calculate EDD by using the following exercises:

Exercise no.1: Mrs. Seema, who is 29 years old, tells you that she has not had a period for the past 4 months. Her last period started on the day before Holi, i.e., March 10 2023. Calculate her due date.

Add 9 calendar months in the month + 7 days in Day’s.

The answer is December 17, 2023.
Exercise no.2: Mrs. Seeta who is 17 years old, says her last period started on January 3, 2023. She wants to know when she will deliver her Baby.
Calculate her Expected due date.
 
Add 9 calendar months in the month + 7 days in Day’s.
 
The answer is October 10, 2023.
Exercise no. 3: Mrs. Kalindi, who is 24 years old, tells you that her last period was on 28 March. She wants to know her expected due date.
What will be her Expected due date.
 
Add 9 calendar months is the months + 7 days in the days.
 
The Answer is January 4, 2023.

Obstetrical Score

Obstetric score helps a person know about the mother’s obstetric history simply at a glance.

GPLAE

G- Gravida means number of times a woman has conceived

P- Parity means number of times she delivered or the foetus crossed the period of viability( 28weeks in India whereas 24 weeks in US)

L – Live births or the number of children living at present

A- Abortions ( spontaneous, MTP, etc)

E- Ectopic pregnancy

Gestational age:

Gestational age (GA) is the duration of pregnancy after the first day of the last menstrual period (LMP), and it is typically represented in weeks and days. This is sometimes referred to as menstrual age. Conceptional age (CA) is the genuine foetal age and refers to the duration of pregnancy from conception.

The three fundamental approaches for estimating gestational age (GA) are menstrual history, clinical examination, and ultrasonography. The first two are prone to significant inaccuracy and should only be used when ultrasonography facilities are unavailable. The date of experiencing the first foetal movements (quickening) is far too unpredictable to be effective. The minimal gestational age can be estimated using the date of the first reported positive pregnancy test and the amount of beta-human chorionic gonadotropin (bHCG). The date of embryo transfer is known in women who conceived via assisted reproduction procedures, which allows them to correctly date their pregnancy. In rare situations, the date of coitus is known, which can be used to calculate the duration of the pregnancy.

The American College of Obstetricians and Gynaecologists (ACOG) recommends ultrasound measurement throughout the first trimester (up to and including 13 6/7 weeks gestation) as the most accurate method for determining or confirming gestational age. If assisted reproductive technology (ART) was utilised during the pregnancy, ACOG recommends that the ART-derived gestational age be used to calculate the projected due date. ACOG recommends that the gestational age and EDD be calculated as soon as data from the last menstrual period (LMP), the first accurate ultrasound examination, or both are available.

For Example:

LMP is 12/12/2023

Date of Assessment is 04/03/2024

We need to calculate all the dates from LMP till the date of assessment they divided by 7, by doing this you will be able to get the exact Gestational age of the mother.

In the December 2023- 20 days

January 2024- 31

February – 29

March-4

Total= 84 days till 4th of march ( date of assessment)

84/7=12

The answer is = 12 weeks of Gestation.

Note= As a health care provider we need to ensure that the LMP must be correct. On the basis of GA finding we can assess the growth and development of the fetus.

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