Understanding the Different Stages of Pregnancy

Although physical changes are obvious through pregnancy, changes to the body during pregnancy occur on a much deeper level. Hormonal changes affect the body in many ways, altering organ function and necessitating a shift in lifestyle.

Because this can be a confusing and potentially overwhelming time, particularly for new mothers, we’ve illustrated the physical and emotional changes that women may experience while pregnant. Expecting mothers may also not realise that time between trimesters is not evenly distributed – generally, the first trimester represents weeks 0-13, the second trimester 13-28 and the third trimester is made up of weeks 28-40.

It’s important to note that because every pregnancy is different, changes we list are not necessarily bound to be experienced by every pregnant woman.


Significant changes occur in the first trimester as the body manages the new pregnancy. Managing these new changes can be overwhelming at first but knowing what to expect makes this task simpler. Cravings or aversions to certain foods is common, as are mood swings – the following are relatively common during this first stage of pregnancy:


Many have heard of morning sickness, but don’t let the name fool you – this nausea can be experienced at any time of the day. If you are experiencing frequent vomiting, it might be wise to consult your doctor regarding nutrition. Heartburn can also accompany this nausea.


Fatigue occurs due to the body beginning to develop the foetus, which will demand the need to rest more regularly. This could entail naps during the day or refraining from doing as much housework as you normally would.

Changes to breasts

Increasing levels of oestrogen and progesterone cause breasts to become tender and appear swollen, and nipples may appear darker. Any issues with soreness can be alleviated with more comfortable bras.


The second trimester is easier to manage than the first trimester, both as a result of becoming accustomed to the pregnancy and the lessening of fatigue and nausea. It is also during the second trimester that women begin to look pregnant, and close to the end of this trimester you’ll be able to feel the baby move!

Change in body shape

General weight gain will also occur, which may cause back pain in some cases.  This increase in weight will also cause you to lose your usual waistline. Greater pigmentation also occurs during this trimester, and a dark line (called the linea negra) will start to appear down your abdomen and stretch marks will begin to form.

Digestive issues

The digestive system slows down the rate at which food is digested during this stage, which might necessitate that you eat smaller, lighter meals more regularly. This slowing down of the digestive system might also cause constipation and occasionally heartburn.


The third trimester represents the final stage before the baby is delivered and makes for a very exciting time. Your baby will begin to move lower into your abdomen as the trimester progresses, which will be physically noticeable.


Unfortunately, the third trimester may involve leakages as your baby grows bigger. Breasts may leak colostrum, a watery pre-milk, and pressure on the bladder can cause urine to leak when coughing or laughing.

Difficulty sleeping

With a considerable increase in size comes difficulty in sleeping. Shortness of breath due to increased mass and the mass itself might make comfortable sleeping positions difficult to achieve. Sleeping on your side usually helps in instances such as this.

Learn more with Dr Tom Cade

Although we’ve given an overview of some of the more prevalent changes occurring during pregnancy, these trimesters offer far more personal experiences than a blog such as this can reflect – if you have any questions regarding pregnancies, or wish to enquire about any specific symptoms, don’t hesitate to get in touch with Dr Tom Cade today.