Pregnancy

Pregnancy Due Date Calculator

Last menstrual period date:

Meaning of Estimated Fertilization Date

Conception usually occurs around 11-21 days after the first day of the last period of a woman who has a regular period. The estimation of conception date is based on this, but is rarely ever exact since it is difficult to know exactly when ovulation occurs. Estimating conception date can also be more difficult for women who have irregular periods, or for those who don’t remember the first day of their last period. In cases like these, one of the more accurate ways to estimate gestational age is through the use of an ultrasound.

Meaning of First, Second and Third Trimesters

A pregnancy is divided into three stages called trimesters: first trimester, second trimester, and third trimester. A trimester lasts between 12 and 14 weeks, while a full-term pregnancy lasts around 40 weeks from the first day of a woman’s last period. In each trimester, the fetus will meet specific developmental milestones.

The First Trimester (0-13 Weeks)

During this period, your baby’s body structure and organs develop. Your body will also undergo major changes, and you may feel nausea, fatigue, breast tenderness and frequent urination. These are all common symptoms, but every woman has her own unique experience.

The Second Trimester (14-26 Weeks)

Known as the “honeymoon period”, the second trimester is when many of the unpleasant symptoms of early pregnancy subside. You’re likely to have increased energy and sleep better. However, some women experience back or abdominal pain, leg cramps, constipation or heartburn.

An ultrasound can determine the gender of the baby as early as 14 weeks, although some doctors may perform your first ultrasound between 18 and 20 weeks. During the anatomy ultrasound, measurements of the baby are taken by an ultrasound technician.

Somewhere between 16-20 weeks, you may feel your baby’s first movements, this is known as “quickening”.

Third Trimester (27-40 Weeks)

You are now nearing the home stretch of your pregnancy and are probably very excited and anxious for the birth of your baby. Some of the physical symptoms you may experience during this period include shortness of breath, hemorrhoids, urinary incontinence, varicose veins, and sleeping problems. Many of these symptoms arise from the increase in the size of your uterus, which expands from approximately 2 ounces before pregnancy to 2.5 pounds at the time of birth.

During the final trimester, your baby’s bones are fully formed, its touch receptors will be fully developed, and the baby’s organs are capable of functioning on their own. As you near your due date, the baby’s body may turn southwards into a head-down position for birth.