The First Trimester

Pregnancy is split into three different periods, each of these three stages involves a certain part of your child’s development. The first trimester is typically the first three months from when your pregnancy started. Different doctors tend to measure when your pregnancy started slightly differently, but the physical characteristics of the trimester are universal in the medical profession.

Typically speaking the first 12 weeks of pregnancy are defined as the first trimester, however of these the first 2 weeks do not involve any pregnancy. These 2 weeks tend to involve your last period, after which the pregnancy begins in earnest.


What happens during the first trimester?

The most well-known effect of pregnancy and a hallmark of the first trimester is the ever dreaded morning sickness. A little known fact however, is that morning sickness isn’t a must and only effects about two thirds of women. The term ‘morning sickness’ itself is also a bit misleading as it can strike at any time of day. The important thing to note is that morning sickness is nothing to worry about, and is a natural consequence of the hormonal changes that occur during pregnancy. One of the key female hormones that is present in high levels during the first trimester is oestrogen, and in high concentrations oestrogen is the culprit responsible for morning sickness.

You may find that you vomit as a consequence of your morning sickness, and if you do it’s always worth mentioning to your doctor, but again this is a perfectly normal part of pregnancy. If you do suffer from some vomiting, then make sure to keep yourself hydrated and to rest if you need to. Another effect of increased hormone levels during the first trimester is a darkening of your nipples and the surrounding areolas.

During the 5th week of your first trimester your baby (referred to by medically as an embryo at this stage) will begin to develop key organs like the heart and brain. The 6th week will see the development of a face and limbs, and at this point the embryo will be a shockingly small quarter inch in length! The developing foetus actually begins to move during the first trimester, which can be a remarkable sight during an ultrasound.

What can I do during the first trimester?

For the best chance for a successful pregnancy and a healthy baby, it is often recommended that you make some lifestyle changes during the first trimester. The obvious big steps are to quit smoking and to stop drinking alcohol, as the chemicals involved in both these practices can have negative health benefits for you and your baby. Your doctor will also talk to you about your diet and making adjustments to ensure that you and your baby receive all the vitamins, minerals, and other nutrients necessary for good health.

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