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Everything You Need to Know About the First Trimester

Early pregnancy can be quite the doozy if you’re unprepared for all that is in store. It’s during this initial phase of pregnancy that expectant moms feel the most nauseated, isolated, hormonal, and nervous. Educating yourself –and your partner– on what to expect during the first 13 weeks is critical to establishing healthy routines, promoting healthy pregnancy, and understanding what your body needs, when it needs it, and why.


What Is The First Trimester?

The first trimester begins on the first day of your last menstrual cycle and runs through the 13th week of gestation (or approximately 3 months). Although you may not look pregnant, you’re more than likely feeling it, and that’s thanks to the flood of pregnancy hormones needed to jumpstart your pregnancy. By the time your 13th week has come to pass, your baby will have grown from a tiny, microscopic embryo to approximately the size of a lemon. Because of these rapid changes to your body, and fluctuations in hormones, you’re bound to experience some (if not all) of the textbook early pregnancy symptoms.


Common First Trimester Symptoms

It’s important to establish that each pregnancy is different –you may experience all, some, or none of the following symptoms:


Morning sickness - Although the title can be misleading, some women experience “morning sickness” (nausea and vomiting) all day long. Regardless of the time of day, this symptom is a result of the uptick in pregnancy hormones –namely hCG and estrogen– needed to help your developing embryo reach its first trimester milestones. This symptom usually begins around week 5, peaks around week 9 or 10, and generally clears up by week 20. As many as 70-85% of women experience morning sickness in the first trimester. Our Morning Sickness Sweets with ginger and B6 is a great item to keep on hand for when those waves of nausea start rolling in. Thankfully, studies have found a silver lining in a connection between morning sickness and a reduced rate of miscarriage, so this sensation is far from all for naught. 


If you’re experiencing excessive vomiting (more than 3-4 times a day) you may have hyperemesis gravidarum which can result in weight loss, dehydration, and other serious complications. If you’re unable to keep solid food down longer than 24 hours, or fluids for longer than 12 hours, seek medical attention. 


Breast tenderness - As your body begins to adapt to carrying life, it also prepares to sustain life through breast milk production. Your breasts undergo some major changes in the first trimester as hormones ready your milk ducts for your upcoming due date. Your breasts may tingle, ache, swell, and develop pink or white stretch marks. Due to increased blood volume and hormones, the veins in your breasts may become more visible and the color of your areolas may darken. 


Fatigue - Your body is working overtime to provide for your growing embryo during the first trimester of pregnancy. Fatigue is common and can be combated by resting when possible and taking frequent naps. Ensuring you’re getting adequate vitamins and minerals like Iron and B vitamins can increase your energy levels as well. Our Total Prenatal + DHA has 100% of the daily values for pregnant women, along with other essential nutrients for a healthy pregnancy and healthy baby. 


Discharge - A thin, milky-white discharge called leukorrhea is normal during pregnancy. These secretions provide lubrication and prevent infection. If your discharge is yellow or green and smells bad, or you’re seeing a lot of clear discharge, you should see your doctor to rule out other medical conditions. 


Food aversions - Everyone talks about pregnancy food cravings, but the antithesis –food aversions– are very real too. If you’re experiencing nausea or vomiting in the first trimester, the mere mention of your once favorite meal or snack can make you retch. Drinking nausea-fighting tea, like our Morning Sickness Tea, with plain crackers or a banana first thing in the morning can help to settle your stomach and make the thought of food more appealing. Additionally, many women experience increased sensitivity to smells during pregnancy which can encourage food aversions.  


Slight cramping - It’s normal to experience mild cramping in early pregnancy. Gas and bloating can exasperate this sensation, and you may also cramp slightly when the egg implants itself into the uterine lining. These experiences are common and should be no cause for concern, however, severe cramping and/or heavy bleeding could indicate a serious medical emergency. The highest risk of miscarriage is during your first trimester –erring on the side of caution is always recommended. 


When To Call Your Doctor?

Each woman responds to pregnancy differently, nevertheless, a few symptoms that warrant a call to your medical provider 100% of the time are:

  • Heavy vaginal bleeding
  • Severe abdominal pain
  • Extreme thirst (could indicate gestational diabetes)
  • Painful urination
  • Fever over 101.5 degrees F, chills, and/or backache
  • Severe puffiness in the hands or face (indication of a life-threatening condition called preeclampsia
  • Blurred vision 

What To Avoid In The First Trimester

During the first trimester, your immune system is preoccupied with the development of your baby. A distracted immune system leaves you more susceptible to foodborne illness, bacteria, and other infections. Additionally, some food items and activities are simply unsafe for pregnant women. A few things to avoid throughout your pregnancy include:

  • The litter box - Cat feces can contain bacteria that cause toxoplasmosis. In early pregnancy, toxoplasmosis can lead to developmental defects.   
  • Hot tubs and saunas - Raising your body temperature above 101 degrees can cause fainting, dizziness, hyperthermia, and dehydration in pregnant women.
  • Alcohol - No amount of alcohol consumption is known to be safe during pregnancy. Drinking alcohol while pregnant can cause fetal alcohol syndrome (FAS) and other complications.
  • Soft serve ice cream and deli meat - These two seemingly harmless food items can harbor listeria if food preparation is not done correctly. Listeriosis infections are rare but can cause pregnancy complications. If you’re craving a deli meat sandwich, heat it to steaming to kill off any potential bacteria before you eat it.
  • Fish that are high in mercury - Fish like wild salmon and anchovies are an excellent source of Omega-3 fatty acids while pregnant, however, fish that contain high levels of mercury like grouper, swordfish, mackerel, and sea bass (to name a few) should be avoided.
  • Cigarettes and smoking marijuana - Smoking is linked to low birth weight, preterm labor, and other complications such as abnormal neurological development.  
  • Raw or undercooked foods - Bacteria can grow on raw, undercooked, or improperly prepared foods. Salmonella, listeria, and the toxoplasma gondii parasite are commonly found in undercooked foods. Infections like these while pregnant can lead to an increased risk of miscarriage, stillbirth, and other complications for your developing baby.

Coping With the Mental Load

Because the majority of miscarriages happen within the first 12 weeks of pregnancy, many couples experience elevated levels of stress and anxiety. Stress causes your body to produce a hormone called cortisol. Elevated cortisol during pregnancy is linked to adverse birth outcomes and may alter fetal development with lasting effects into adolescence and adulthood. 

Finding healthy ways to limit and reduce stress is critical in the first trimester. Some pregnancy-safe stress-reducing activities include:

  • Yoga
  • Going for a walk
  • Reading a book outside
  • Meditation
  • Stretching
  • Resting
  • Sipping on tea
  • Confiding in a loved one

How Is The Baby Developing In The First Trimester?

The main thing to remember here is that all the nausea and vomiting, fatigue and flatulence, is a physical reaction to the increase in pregnancy hormones that indicate your pregnancy is developing as it should. 


There are lots of exciting changes happening to your baby during the first trimester. At your first ultrasound (around week 6 of pregnancy), your baby will probably resemble a kidney bean –but by week 12, you’ll see a whole tiny human up on that screen. Here are just a few of the highlights from those early weeks of development:

Heart - By week 5 your baby has a heartbeat, an erratic one, but still strong enough to be picked up on an ultrasound.

Eyesight - The optic nerve that will eventually connect your baby’s eyes and brain is developing as early as week 5, by week 8 the retina will begin forming.

Hair, nails, and skin - Skin begins to form around weeks 5-8, with hair follicles and nail beds forming in week 11.

Bones - Your baby's bones begin to form in weeks 6-10, by the 6th week you’ll be able to discern arms, legs, hands, and feet. By week 10 you’ll be able to see fingers and toes too.

Sense of touch - By week 8 your baby will already have formed touch receptors –basic units of the nervous system that respond to touch and other similar stimulation.

Brain- Around week 8 your baby’s brain begins to form. Taking a prenatal with DHA and folic acid before becoming pregnant (or as soon as possible) is important as DHA is necessary for the proper formation of the brain, eyes, liver, and skeletal muscle, while folic acid protects against neural tube defects.


The first trimester is a time of rapid changes for you and your baby, but there is much needed relief on the horizon. As you inch closer and closer to that glorious second trimester, the most uncomfortable symptoms of early pregnancy like the nausea, vomiting, and fatigue will lessen. The important thing to keep in mind, is that with each passing day (no matter how exhausting) you’re on the path to motherhood and we can’t think of a better, more worthwhile journey. 


If you’re interested in learning more about the early stages of pregnancy and how it affects your body, we recommend reading:

Ways Your Body Changes During Pregnancy

Pregnancy Cramps: What’s Normal and When to Worry

Working While Pregnant: Knowing Your Rights

Pregnancy Morning Sickness & Nausea: A Good Sign?