The Pregnancy Guide: Your First Trimester

So, you’ve found out you’re pregnant! Whether you’ve been pregnant before or this is your first time, it’s important that you know what’s happening with your body and what to expect during your first trimester.

Did you know that the first trimester actually starts before you’re pregnant? Your “week one” begins with the last day of your most recent period, meaning that by the time the egg is fertilized, it’s roughly your third week of pregnancy. Your first trimester then lasts until week thirteen.

Let’s take a look at some of the key things to consider during these first thirteen weeks.

How to Set Up a Healthy Pregnancy

These weeks one through thirteen are considered a critical period for your baby’s development. This is because your baby is beginning to form its major organs. And this means that exposures to toxins, infections and harmful substances could increase your child’s risk of being born with complications or congenital disorders.

In order to help protect your baby, you should avoid drinking alcohol, smoking cigarettes, and using recreational drugs. Consider changing your diet to avoid raw meats and seafood, lunchmeats, and unpasteurized cheeses or drinks, as these foods are more likely to expose you and your baby to harmful bacteria. It’s also important to limit your contact with others who are sick.

It’s also highly recommended that you take a prenatal vitamin: particularly one that includes folic acid. Folic acid is an important mineral for your baby’s development. Research has shown that when mothers do not consume enough folic acid their babies have a much higher risk of developing neurological problems.

Body Changes You May Experience

1. Morning Sickness

The infamous morning sickness: it can be experienced differently depending on the woman, but often includes nausea at different times throughout the day. Morning sickness is frequently worst during weeks 8-12 and improves with the second trimester.

If you experience vomiting to the point of weakness, dizziness, or you are so dehydrated that you stop peeing, you should make an appointment to be seen by your healthcare provider.

2. Frequent Urination

During the first trimester you’ll likely become friends with the bathroom both from morning sickness as well as needing to pee frequently. This frequent urination is because of the pregnancy hormone HCG, the same hormone detected in pregnancy tests. HCG causes your body to send extra blood to your pelvic region and tells your kidneys to work harder because you retain more fluid during pregnancy.

3. Swollen or Tender Breasts

Tender breasts are another symptom that you can blame the hormones for. Your pregnancy hormones, particularly the increased estrogen and progesterone, cause the mammary glands in your breasts to grow bigger.

4. Constipation and Heartburn

Your digestive system slows down (also thanks to the hormone changes). As pregnancy increases the hormone progesterone in your body, progesterone reduces the contractions of your intestines. This means that food doesn’t move through your digestive tract as fast as it used to.

References

1. “The First Trimester” Johns Hopkins Medicine, Johns Hopkins Medicine
2. “First Trimester” Cleveland Clinic, Cleveland Clinic. 22 August 2022.