Pregnancy & Fetal Development Overview

Pregnancy & Fetal Development

• Pregnancy and fetal development are topics of study.
• Objectives include defining family and family-centered care, examining conception and, explaining fetal growth and development, and identifying a nurse's role in educating and promoting health during pregnancy.
• Family is defined biologically, legally, or as a social network with personally constructed ties and ideologies. It can also be defined by the individuals themselves.

Current Trends & Family Forms

• Families are smaller.
• People are delaying childbirth.
• Some individuals are choosing not to have children.
• Blended families, single-parent families, and LGBTQ2S+ families are increasingly common.
• Canada's population is aging.

Fertilization & Conception

• Conception occurs when sperm and ovum unite, fertilizing the ovum and forming a zygote.
• This happens in the outer third of the fallopian tube.
• The sex of the zygote is determined at fertilization.
• Fraternal twins are formed by two ova fertilized by two different sperm.
• Identical twins come from one fertilized ovum that splits into two embryos.

Fetal Development Stages

• Fetal stages are: zygote, embryo, and fetus.
• Zygote: 1st week of development, implantation occurs, the blastocyst buries itself in the uterine lining. Human chorionic gonadotropin (hCG) is produced.
• Embryo: Weeks 2-8, development of the conceptus into an embryo. Differentiation begins, forming the three germ layers (ectoderm, mesoderm, and endoderm).
• Fetus: Week 9 to birth, major development of the fetus.

Ectoderm, Mesoderm, and Endoderm

• Ectoderm: Outer layer of cells. Forms skin, hair, nails, and the external nervous system.
• Mesoderm: Middle layer. Forms the skeletal, muscular, and circulatory systems.
• Endoderm: Inner layer. Forms the linings of lungs, urinary and digestive tracts.

Amniotic Fluid

• Fills the amniotic cavity and serves four main functions:
• Physical protection
• Prevents the sac from adhering to the skin
• Acts as a barrier to infection
• A cushion for protection, temperature regulation, and unrestricted movement.

Placenta

• Connects the fetus to the mother.
• Produces hormones to sustain pregnancy.
• Supplies the fetus with oxygen and nutrients.
• Transports waste products.
• Acts as a barrier to certain substances and functions as an endocrine gland.

Umbilical Cord

• Connects the fetus to the placenta.
• Contains two arteries carrying deoxygenated blood to the placenta and one vein carrying oxygenated blood back to the fetus.
• Wharton's jelly surrounds the three vessels.

Maternal Changes During Pregnancy

• Reproductive System: Include changes in uterus weight, structure and location. Enlargement is essential to accommodate the growing fetus, placenta, and amniotic fluid. These changes also occur in the cervix, ovaries and vagina such as vascularity and glandular tissue development, and mucus plugs formation. Also included are changes to breast tenderness, areola pigmentation.
• Respiratory System: Breathing rate slightly increases in pregnancy (2-3 breaths). Nasal congestion (edema in nasal mucosa due to vasocongestion), and increase in oxygen consumption also occur.
• Cardiovascular System: Blood volume increase substantially (45%), cardiac output enhances, heart rate increases (10-15 beats per minute), and supine hypotensive syndrome, and clotting factors are also implicated.
• Gastrointestinal (GI) System: Stomach and intestines are displaced, leading to potential discomfort. Appetite and thirst, stomach emptying and intestinal motility are altered. Renal demands increase, and water retention might occur. Risk of urinary tract infections (UTIs) is heightened.
• Integumentary System: Include changes in skin pigmentation such as chloasma (mask of pregnancy), and stretch marks known as linea gravidarum or pregnancy lines.

Signs of Pregnancy

• Presumptive signs: Possible signs of pregnancy, subjective, could have other causes beyond pregnancy (e.g., amenorrhea, nausea, breast changes, urinary frequency, fatigue).
• Probable signs: Signs detected by a trained examiner (e.g., Goodell's sign, Chadwick's sign, uterine enlargement, Braxton Hicks contractions, pregnancy tests).
• Positive signs: Diagnostic signs only possible during pregnancy, include fetal heart sounds, fetal movement noted by the examiner, visualization of fetus by ultrasound.

Nagele's Rule

• Used to determine the estimated date of delivery (EDD).

Psychosocial Adaptation

• Potential obstacles to pregnancy include inadequate finances, knowledge gaps about community resources, lack of transportation, daycare or elder care problems, domestic violence, stress, and nutritional issues.

Impact of Pregnancy on Adolescents

• Adolescents may experience anxiety and conflict concerning how to break the news to their parents and partner's families.
• Teenage pregnancy can involve relationship concerns, shame, guilt, and fear.
• Teens must handle the transition of becoming a parent along with existing stresses.

Discomforts of Pregnancy

• Common discomforts during pregnancy include urinary frequency, nausea and vomiting, indigestion/heartburn, constipation and hemorrhoids, edema of lower extremities, varicose veins, increased vaginal discharge, fatigue, backache, leg cramps, dyspnea, nasal stuffiness.

Danger Signs for Alerting Providers

• Serious signs during pregnancy that requires immediate attention include vaginal bleeding, swollen face or fingers, severe or constant headache, vision changes, abdominal pain, chills and fever, persistent vomiting, sudden gush of fluid from the vagina.