Pregnancy

• Pregnancy is the period during which a fertilized egg (zygote) develops into a fetus inside the uterus of a female.

• It usually lasts around 40 weeks, or about 9 months, from the first day of the last menstrual period (LMP) and is divided into three trimesters.

Signs and symptoms of pregnancy:

Early Signs and Symptoms

1. Missed Period: Often the first and most noticeable sign of pregnancy, especially if you have a regular menstrual cycle.

2. Tender and Swollen Breasts: Hormonal changes in early pregnancy can make breasts feel sore, sensitive, or heavier than normal.

3. Fatigue: The rise in progesterone levels can lead to feelings of tiredness and exhaustion, even in the early stages of pregnancy.

4. Nausea and Vomiting: Widely known as "morning sickness," this symptom can occur at any time of the day and is most common during the first trimester, though it can extend beyond for some women.

5. Increased Urination: The need to urinate more frequently is prompted by hormonal changes and an increase in blood volume.

Other Common Symptoms

1. Mood Swings: Emotional fluctuations are common, caused by changes in hormone levels.

2. Food Cravings or Aversions: It's not unusual for pregnant women to have a strong desire for certain foods or an aversion to others, a phenomenon driven by hormonal variations.

3. Constipation and Bloating: Slower digestive processes, due to hormonal effects, can lead to constipation and a bloated feeling.

Confirmation of Pregnancy

1. A Positive Pregnancy Test: The most definitive early sign of pregnancy is a positive result on a pregnancy test, which detects the presence of the hormone human chorionic gonadotropin (hCG).

Stages of pregnancy:

First Trimester (Weeks 1-12)

Development and Changes:

I. Fertilization:

• The journey begins when a sperm cell fertilizes an egg, forming a zygote. This marks the conception and the start of pregnancy.

II. Implantation:

• The zygote divides multiple times, becoming a blastocyst, which implants itself into the uterine lining approximately 6-10 days after fertilization. This process establishes the foundation for the embryo's growth.

III. Placenta and Embryo Development:

• The blastocyst differentiates into the embryo and the placenta. The placenta plays a crucial role, acting as a life-support system that delivers nutrients and oxygen to the developing fetus.

IV. Organogenesis:

• During this critical phase, the embryo's organs start to form. Key developments include the neural tube (which becomes the brain and spinal cord), the heart, and limb buds.

V. Fetal Heartbeat:

• By around 6-8 weeks of gestation, the fetal heartbeat can be detected through ultrasound, marking a significant milestone in the embryo's development.

Second Trimester (Weeks 13-27)

Growth and Maternal Changes:

 I. Continued Fetal Growth and Development:

• The fetus undergoes rapid growth, and its features become more defined, including facial features, fingers, and toes.

II. Fetal Movements:

• Between 16-20 weeks, the mother may start to feel the fetus's movements, known as quickening, indicating active fetal development.

III. Fetal Sex Determination:

• Around 18-22 weeks, the fetus's genitalia can be distinguished on an ultrasound, allowing parents to learn the sex of their baby.

 IV. Vernix Caseosa and Lanugo:

• The fetus develops a protective, waxy coating called vernix caseosa and a fine hair called lanugo, both of which help regulate body temperature and protect the skin.

V. Maternal Changes:

• As the fetus grows, the mother's uterus expands, leading to various physical symptoms, including backaches, leg cramps, and heartburn.

Third Trimester (Weeks 28-40)

Preparation for Birth:

I. Fetal Growth and Development:

• The fetus continues to gain weight and further develop its organ systems, preparing for life outside the womb.

II. Fetal Position:

• Most fetuses move into a head-down position, which is optimal for birth.

III. Braxton Hicks Contractions:

• These are irregular, non-painful contractions that occur as the body prepares for labour.

IV. Lightening:

• The fetus "drops" lower into the pelvis, reducing pressure on the mother's diaphragm and making breathing easier.

 V. Labor and Delivery:

• The final stage of pregnancy culminates in labour and delivery, where contractions become regular and more intense, leading to the birth of the baby.