Week 13 of Pregnancy: Goodbye Nausea. Mood and Energy Changes
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Motherhood


Week 13 marks the beginning of the second trimester, a stage when many women begin to feel more energetic and experience fewer discomforts. The risk of miscarriage decreases significantly, and the baby’s development progresses rapidly.

Increased energy and less nausea
Many women experience a decrease in nausea and an increase in energy levels, making it easier to resume daily activities.
Abdominal growth
The uterus begins to expand beyond the pelvis, which may make the abdomen appear more rounded.
Increased appetite
As nausea decreases, appetite usually increases. It is important to choose healthy foods and control portions to avoid excessive weight gain.
Skin changes
The “pregnancy glow” may appear due to increased blood flow and natural oil production. Some women also begin to notice the linea nigra (a dark line on the abdomen) or melasma (skin spots).
Nasal congestion
Increased blood flow and hormonal changes can cause inflammation in the nasal membranes, resulting in congestion or a stuffy nose sensation.
Gum sensitivity and bleeding
Hormones can make gums more sensitive and prone to bleeding when brushing teeth. Using a soft brush is recommended, and consult a dentist if bleeding is constant.
Increased vaginal discharge
It is normal for vaginal discharge to increase due to hormonal changes. As long as it does not have a bad odor or abnormal color, it is usually not a cause for concern.
Constipation and gas
Progesterone continues to affect digestion, which can cause constipation, bloating, and gas buildup. It is important to consume fiber and stay well hydrated.
Occasional headaches
Some women may experience mild headaches due to hormonal changes and increased blood volume. Resting, staying hydrated, and avoiding stress can help reduce them.
Dizziness or lightheadedness
Increased blood flow and changes in blood pressure can cause episodes of dizziness. It is advisable to avoid sudden position changes and stay well hydrated.
This week, the baby measures approximately 7 to 8 centimeters long, similar to the size of a peach or large plum. Its weight is around 25 grams, although it will continue to grow rapidly in the coming weeks.
Physical Development and Organs
Nervous System and Reflexes
Proteins → Support the development of the baby’s muscles and tissues.
Sources: Lean meats, chicken, fish, eggs, legumes, tofu, and nuts.
Iron → Prevents anemia and helps transport oxygen.
Sources: Red meat, spinach, lentils, chickpeas, fortified cereals.
It is recommended to combine with foods rich in vitamin C (oranges, strawberries, kiwi) to improve absorption.
Calcium → Essential for the formation of the baby’s bones and teeth.
Sources: Milk, yogurt, cheese, almonds, broccoli, and sardines.
Folic acid → Prevents neural tube defects.
Sources: Spinach, asparagus, lentils, broccoli, avocado, nuts, and fortified cereals.
Omega-3 → Supports the baby’s brain and eye development.
Sources: Low-mercury fish (salmon, sardines, trout), chia, flaxseed, and walnuts.
Fiber → Prevents constipation, a common symptom at this stage.
Sources: Fruits, vegetables, whole grains, and legumes.
Water → Maintains good hydration and helps blood circulation.
It is recommended to drink at least 2 liters of water per day.
Foods to Avoid
Fish with high mercury content (bluefin tuna, swordfish, shark).
Deli meats and raw or undercooked meats.
Unpasteurized dairy products.
Excess caffeine (no more than 200 mg per day, equivalent to one cup of coffee).
Ultra-processed foods or those high in sugar and saturated fats.

General Recommendations
Eat several times a day in balanced portions.
Do not skip meals to avoid blood sugar drops or fatigue.
Choose healthy snacks such as yogurt, nuts, or fresh fruit.
Consult with your doctor if additional supplementation is needed.

Recommended Exercises
Daily walks.
Swimming or water aerobics.
Prenatal yoga or Pilates.
Strengthening and stretching exercises.
Exercises to Avoid
Contact sports or those with risk of falls.
High-impact exercises.
Heavy weightlifting.
Traditional abdominal exercises.
Benefits for the Mother
Improves blood circulation → Reduces the risk of swelling and varicose veins.
Decreases the risk of gestational diabetes → Helps regulate blood sugar levels.
Relieves muscle and back discomfort → Strengthens muscles and improves posture.
Prevents constipation → Promotes intestinal transit.
Increases energy and reduces fatigue → Improves mood and combats tiredness.
Decreases stress and anxiety → Releases endorphins that promote relaxation.
Promotes better rest → Contributes to deeper and more restorative sleep.
Prepares the body for childbirth → Strengthens pelvic floor muscles and physical endurance.
Benefits for the Baby
Better oxygenation and blood flow → Supports the baby’s development in the uterus.
Lower risk of excess birth weight → Contributes to healthy growth.
Early stimulation → Exercise movements and rhythm can stimulate the baby’s neurological system.
Consume Harmful Substances
Alcohol: Can affect the baby’s development and increase the risk of malformations.
Tobacco and nicotine: Smoking can cause low birth weight, premature birth, and respiratory problems in the baby.
Recreational drugs: Can cause severe damage to the baby’s nervous system.
Consume High-Risk Foods
Fish with high mercury content (bluefin tuna, swordfish, shark, king mackerel).
Raw or undercooked meats and eggs → May contain dangerous bacteria such as salmonella or listeria.
Unpasteurized cheeses and dairy products → May contain listeria and increase the risk of infections.
Deli meats and raw seafood → Risk of toxoplasmosis and other infections.
Engage in High-Impact or Dangerous Exercise
Avoid contact sports such as soccer, basketball, or skiing.
Do not perform exercises with risk of falls, such as cycling on uneven terrain or horseback riding.
Avoid exercises that involve lifting too much weight or intense abdominal exercises.
Exposure to Toxic Substances
Avoid cleaning products with strong chemicals (bleach, ammonia).
Do not come into contact with paints, solvents, or pesticides.
Spend Too Much Time in Hot Environments
Avoid saunas, steam baths, and hot tubs, as excessive heat can be dangerous for the baby.
Do not exercise in very hot environments or under intense sun.

Self-Medicate
Do not take medications without consulting your doctor, even if they are over-the-counter.
Avoid herbal supplements without medical supervision.
Sleep on Your Back for Extended Periods
Starting in the second trimester, sleeping on your back can affect circulation due to the weight of the uterus on the vena cava. It is recommended to sleep on your side, preferably on the left side.
Skip Meals or Not Stay Hydrated
Do not go many hours without eating, as it can cause dizziness or blood sugar drops.
Avoid dehydration by drinking enough water throughout the day.
Yes, many women begin to feel less nausea and fatigue when entering the second trimester. However, some may still experience them for a few more weeks.
The uterus begins to expand beyond the pelvis, so some women notice slight abdominal growth, although in others it may not be very evident yet.
Yes, but it is important to choose safe exercises such as walking, swimming, or prenatal yoga. High-impact sports or those with risk of falls should be avoided.
Yes, it may be due to stretching of the uterine ligaments. As long as the pain is not intense or constant, it is a common symptom of uterine growth.
Weight gain varies for each woman, but on average it is recommended to have gained between 1 and 2.5 kg in the first trimester.
Yes, in most cases it is safe to travel in the second trimester. It is recommended to consult with your doctor, especially for long trips or air travel.
Some doctors recommend waiting until the second trimester to do so, using ammonia-free dyes in well-ventilated spaces.
Increased vaginal discharge is normal due to hormonal changes. As long as it does not have a bad odor or abnormal color, it is usually not a cause for concern.
Yes, changes in blood pressure and increased blood volume can cause dizziness. To avoid them, it is recommended to stay well hydrated and rise slowly when changing position.
Yes, although the neural tube is already formed, folic acid remains important for the baby's development. Your doctor may recommend combining it with other supplements.
