Question

Describe strategies for confirming pregnancy and estimating the date of birth.

Answer 1

Pregnancy or gestation describes the period in which a fetus grows inside a women's womb or uterus. Human pregnancy is divided into three trimesters and delivery of baby takes more or less than 40 weeks from the last menstrual period.

The strategies for confirming pregnancy is based on presumptive and probable signs. Presumptive sign includes amennorhea ( absence or menstruation), nausea and vomiting, increased frequency of urination, breast tenderness etc. Probable signs are detected by the examiner based on the physical changes in the uterus such as enlargement, placental souffle, braxton hicks contraction, ballottement ( feeling of fetus floating inside uterus) and a positive pregnancy test. Positive attributed to the fetus includes obtaining fetal heart beats and viable fetus seen in ultrasonography.

The estimated date of birth (EDB) is determined based on the first day of the last menstrual period (LMP) and ultrasound examination. The most accurate assessment to estimate the date of birth is mainly based on the measurement of embryo or fetus during ultrasound examination.

The common formula for calculating the estimated date of birth is Naegele's rule/ Naegele's formula. This formula assumes that the fertilization occurs in the 14th day of the 28 day cycle. Naegele's rule involves simple calculation. Add seven days to the first day of LMP and then subtract 3 months. We get the Estimated date of birth.

Example: If LMP is on 4th january 2020. Add 7 days to it we get 11 january 2020. Then subtract 3 months, we get 11 October 2020. 11th October 2020 is estimated date of delivery.