Pregnancy Trimesters Breakdown

Knowing what to expect during your pregnancy can be very overwhelming at the start. When do I call my doctor? When will the sickness stop? What is Braxton Hicks?

Thankfully for us, Drugwatch has kindly allowed us to share this awesome breakdown of each trimester for expecting mums. So go make yourself a cuppa and get informed. 


The first trimester lasts 12 weeks, beginning with conception. During this trimester, substances such as alcohol, illicit drugs, certain medicines, and illnesses can do the most damage to the fetus. According to the American College of Obstetricians and Gynecologists, this trimester is also the riskiest for miscarriages, with approximately 80 percent occurring in the first trimester.

After eight weeks, the embryo becomes a fetus and is one inch to an inch and a half long. By week 12, the fetus begins to move more frequently, and its genitals are developed. Eyelids, toenails, and fingernails appear.

From week one through four, women usually experience symptoms such as breast tenderness, mood swings, constipation, bloating, and heightened senses — such as taste and smell. Morning sickness begins around week six for some women. This may last until the second trimester.

Weeks seven and eight bring symptoms such as frequent urination, headaches, and extra saliva. Reduced blow flow may cause some women to have dizzy spells throughout the day.

First Doctor’s Visit

Women should schedule their first doctor’s visit sometime during weeks six through eight or after their menstrual period is two to four weeks late. Some doctors will not schedule the first exam until week eight unless there is an issue.

During the first visit, the doctor will ask many questions about the woman’s health, habits, and menstrual cycle. The doctor will also perform a number of tests or exams. Women of different ethnic backgrounds often take different tests because they may be at a higher risk for certain diseases.

Exam Timeline

If the initial exam does not produce warning signs women generally see the doctor on a set schedule. Between the 10th and 14th weeks, women may be screened for substances that could point to risk factors for later complications. Between 24 and 28 weeks, pregnant women are tested for gestational diabetes, a type of diabetes that forms during pregnancy. Women who are at higher risk for gestational diabetes may be tested sooner.

Pregnant women typically see their doctor:

  • Every four weeks until the 28th week
  • Every two weeks from weeks 28-36
  • Once a week from week 36 to delivery


The second trimester lasts from week 13 to week 28.

As early as week 12, but usually around week 16, a doctor can determine the sex of the fetus. Bones, muscle tissue, and skin have formed by then.

Women usually feel movement around the 20th week. Around the 24th week, footprints and fingerprints are formed and the fetus sleeps and wakes frequently. The size and shape of the woman’s uterus may also be measured in the 22nd week to determine whether the fetus is growing and developing normally.

The 28th week is usually the earliest a baby can be born, with an estimated 92 percent of babies surviving birth at that time. However, most are born with serious health complications.

False Labour Pains

In the second trimester, women may begin to feel Braxton Hicks contractions, also called “false labor pains.” These sensations come and go and are usually mild.

During this trimester, many of the uncomfortable symptoms of pregnancy subside. Women may have more energy, increased appetite, and higher sex drive for the first few weeks.

Some women may experience nasal congestion, tender gums, and leg cramps. Backaches are common, as is slight brain fog. Because of fluid retention, fingers may feel tingly. Women also gain weight regularly until the baby is born.

Many women are pleased to notice their skin and hair look healthier.

To avoid symptoms of heartburn, women can eat smaller, non-greasy meals and avoid lying down after eating.

Women may begin to feel the “false labour pains” referred to as Braxton Hicks contractions. Typically, these start around week six, but women don’t feel them until the second or third trimester.

This is the body’s way of preparing for true labour. Braxton Hicks contractions feel like a mild menstrual cramp or abdominal tightening that comes and goes. This is a normal part of pregnancy and is nothing to worry about.

Unlike real contractions, Braxton Hicks contractions are mild, occur in the front of the abdomen or one specific area, and last from 30 seconds to two minutes. They are also inconsistent and sometimes subside when the woman moves or changes positions.

Real contraction pain starts in the back and wraps around the abdomen. It also becomes stronger with movement or position change and gets more intense with time.


The third trimester lasts from week 29 to week 40, or until birth.

Around the 32nd week, the fetus’s eyes can open and close and the bones are almost fully formed. An infant born before the 37th week (preterm) is at an increased risk for developmental, hearing, and visual problems.

Infants born during the 37th and 38th (early term) weeks face less serious health risks but are usually not as healthy as babies born in the 39th and 40th weeks (full-term). Babies born during the 41st week (late-term) and after 42 weeks (post-term) are also at a higher risk for complications.

During this trimester, women may feel more tired and develop hemorrhoids. The body experiences more aches and pains. Stretchmarks may appear because of swelling and stretching of the skin. Breasts will leak as they prepare for breastfeeding. If women have sex, they may have spotting after.

If Braxton Hicks's contractions didn’t start in the second trimester, they will begin around week 29. Women can sleep through one of these weak, false labour pains. If changing positions doesn’t make them go away, they will eventually go away on their own.

True labour contractions last between 30 and 90 seconds and increase in duration, coming closer together, as it gets closer to delivery time.