Question 1

How is the due date calculated?

Accepted Answer

The standard method is Naegele's rule: add 280 days (40 weeks) to the first day of your last menstrual period (LMP). This assumes a 28-day cycle. For longer or shorter cycles, the due date is adjusted accordingly. Only about 5% of babies are born on their exact due date.

Question 2

What if my periods are irregular?

Accepted Answer

If your cycles are irregular, Naegele's rule may not be accurate. An early ultrasound (7-12 weeks) is the most accurate way to estimate gestational age and due date. Your doctor may adjust your due date after the first ultrasound.

Question 3

What is a trimester?

Accepted Answer

Pregnancy is divided into three trimesters: First trimester (weeks 1-13): major organ formation, highest miscarriage risk. Second trimester (weeks 14-26): most comfortable period, fetal movement felt. Third trimester (weeks 27-40): rapid growth, preparing for birth.

Question 4

When is a baby considered full term?

Accepted Answer

A baby is considered full term at 39-40 weeks. Early term is 37-38 weeks, late term is 41 weeks, and post-term is 42+ weeks. Babies born before 37 weeks are preterm. Most doctors prefer to wait until 39 weeks for elective deliveries when possible.

Question 5

What is the conception date?

Accepted Answer

The conception date (fertilization date) is typically 2 weeks after the first day of your last period, around ovulation. However, sperm can survive 3-5 days in the fallopian tubes, so conception can occur several days before or on the ovulation day.

Question 6

What prenatal care should I get in the first trimester?

Accepted Answer

First trimester care includes: confirming pregnancy and due date, blood tests (blood type, Rh factor, CBC, STI screening), urine tests, first trimester screening for chromosomal abnormalities (10-13 weeks), nuchal translucency ultrasound, and starting prenatal vitamins with folic acid.

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