Learn the key signs of pregnancy, early symptoms, changes by trimester, and common health complications. A practical and medically accurate guide for expectant mothers.
Pregnancy is a complex physiological process during which a fetus develops within the woman’s body. A normal pregnancy lasts an average of 40 weeks or 280 days, counting from the first day of the last menstrual period. This period is divided into three trimesters, each characterized by specific phases of fetal development and changes in the mother’s body.
Early detection and timely registration for prenatal care are critical for the health of both mother and child. This article provides a detailed overview of pregnancy symptoms, body changes at various stages, and common health complications.
Pregnancy calculator
Calculating the due date is one of the first steps in planning the coming months. A pregnancy calculator is a simple digital tool that helps determine the approximate date of delivery and calculate the current week of pregnancy. It is the first assistant women usually use upon learning of their pregnancy to navigate their new timeline.
Calculate your due date
*This pregnancy calculator provides only an estimated date based on a 280-day cycle. Your doctor will determine the exact date based on ultrasound data.
How does a pregnancy calculator work?
Most calculators are based on Naegele’s rule. The calculation is based on the assumption that pregnancy lasts 280 days or 40 weeks, counting from the first day of the woman’s last menstrual period. To get a result, follow these steps:
- Identify the first day of your last period. You need to know this date; even if the bleeding was light that day, use the very beginning for the calculation.
- Select the date: In the pregnancy calculator window, click the calendar icon and select the relevant date.
- Press “Calculate”: After pressing the button, the screen will display the date corresponding to the 40th week of pregnancy.
Pregnancy signs and early diagnosis
The onset of pregnancy is accompanied by significant hormonal fluctuations, especially an increase in human chorionic gonadotropin (HCG), progesterone, and estrogen levels. These changes cause a range of physical and emotional symptoms even before clinical confirmation.
Missing a menstrual cycle
The most visible sign of pregnancy for women with a regular cycle is a delayed period. After fertilization, the body begins to produce the HCG hormone, which prevents the breakdown of the inner lining of the uterus (endometrium), thus stopping menstrual bleeding. However, it should be noted that delays can also be caused by stress, hormonal disorders, significant weight changes, or illness.
Implantation bleeding
Approximately 6–12 days after fertilization, when the embryo attaches to the uterine wall, slight spotting or cramping similar to a light period may occur. This is called implantation bleeding. It is usually shorter and less intense than a regular period.
Breast sensitivity and changes
Due to hormonal changes, breasts may become sensitive, painful, or swollen as early as one to two weeks after fertilization. The nipples (areolas) may darken and increase in diameter. The body begins to prepare for the lactation process early on.
Fatigue and weakness
Elevated progesterone levels in early pregnancy often cause marked sleepiness and fatigue. The body consumes significant energy resources to support rapid fetal development and placenta formation. Fatigue is also promoted by increased blood production intensity and lower blood pressure.
Nausea and vomiting
The so-called “morning sickness” can occur at any time of the day. It usually begins around the sixth week of pregnancy and often subsides after the end of the first trimester. While the exact cause is not fully understood, it is linked to the rapid rise in HCG levels. In severe cases, hyperemesis gravidarum develops—a condition requiring medical intervention due to the risk of dehydration.
Other common early signs
- Frequent urination: As the uterus enlarges and blood circulation in the kidneys increases, the need to visit the toilet becomes more frequent.
- Sensitivity to smells and taste changes: Many women report an increased reaction to certain smells or a sudden dislike for previously favorite foods.
- Mood swings: The hormonal “cocktail” can affect neurotransmitters in the brain, causing emotional instability.
Pregnancy symptoms
The course of pregnancy is divided into three stages, each dominated by different physiological processes and symptoms.
First trimester – weeks 4 to 13
This is the most critical period for the formation of the fetus’s organ systems. During this time, there is the highest risk of miscarriage. In addition to the symptoms mentioned above, a woman may experience increased vaginal discharge and mild cramping in the uterine area related to stretching. Most energy is devoted to forming the placenta.
Second trimester – weeks 14 to 27
For many women, this is the most comfortable period. HCG levels stabilize, and nausea usually decreases or disappears. Energy levels increase.
- Abdominal enlargement: The uterus grows out of the pelvic cavity, and the pregnancy becomes visually noticeable.
- Fetal movements: Around weeks 18–22 (earlier for subsequent pregnancies), the woman begins to feel the first fetal movements.
- Skin changes: Pigmentation spots on the face (chloasma) or a dark line on the abdomen (linea nigra) may appear. Stretch marks may form due to hormones.
- Ligament pain: As the uterus grows, the round ligaments holding it are stretched, causing sharp pain in the lower abdomen or groin.
Third trimester – weeks 28 to 40
The fetus gains weight rapidly, and the uterus reaches its maximum size, creating mechanical pressure on surrounding organs.
- Physical discomfort: Increased weight puts stress on the spine and joints. Pressure on the diaphragm can make breathing difficult, and pressure on the stomach can promote heartburn.
- Edema: Fluid retention can cause swelling of the ankles, feet, and hands. Sudden and severe swelling (including the face) may indicate preeclampsia.
- Braxton-Hicks contractions: The uterus begins “training” for labor with irregular, painless contractions. Unlike real labor pains, they do not increase in intensity or frequency.
Pregnancy – health problems and complications
While most pregnancies proceed without serious complications, specific health conditions require increased medical supervision.
Gestational diabetes
This is a type of diabetes first diagnosed during pregnancy. Hormones produced by the placenta can block insulin action in the mother’s body, leading to high blood sugar levels. Uncontrolled gestational diabetes increases the risk of fetal macrosomia (excessive birth weight) and preeclampsia for the mother.
Preeclampsia
A serious complication usually developing after the 20th week, characterized by high blood pressure (hypertension) and protein in the urine (proteinuria). Symptoms include severe headaches, vision changes, and sudden swelling. Untreated, it can lead to eclampsia (seizures). The only effective treatment is delivery.
Iron deficiency anemia
Blood volume increases significantly during pregnancy to supply the fetus. If the mother does not receive enough iron, hemoglobin levels drop, leading to fatigue, dizziness, and shortness of breath.
Constipation during pregnancy
Affecting 30–50% of pregnant women, constipation is caused by progesterone relaxing smooth muscles (including the intestines) and the growing uterus physically obstructing the digestive tract.
Diarrhea during pregnancy
Though less common, estrogen fluctuations can cause bowel sensitivity and accelerated emptying.
Placental pathologies
- Placenta previa: The placenta covers the cervix, often requiring a C-section.
- Placental abruption: The placenta separates from the uterine wall prematurely; this is a medical emergency.
Infections
Infections like rubella, CMV, toxoplasmosis, and STIs (HIV, Hepatitis B) can be dangerous. Routine screening is vital for early detection and risk reduction.
When to see a gynaecologist?
Timely diagnosis and professional care ensure a healthy pregnancy. At “Republikas laukuma klīnika” in Riga, professional gynecologists and certified midwives provide comprehensive prenatal care.
Dr. Kristina Bojuta
Dr. Viktorija Margevičus
Dr. Evelīna Geceviča
FAQ
Earliest signs: 6–12 days after fertilization.
Positive test result: 10–14 days.
Typical symptoms: Around weeks 3–4.
Avoid raw meat, raw fish, and unpasteurized dairy. Avoid hot baths, saunas, and lifting heavy objects. Take extra care when cleaning cat litter to avoid toxoplasmosis.
HCG levels rise after implantation (6–12 days post-conception). If tested too early, results may be negative. For faster results, a blood serum HCG test is recommended.
