OB1

Overview of Pregnancy Education

Today’s lesson will focus on pregnancy, with a promise of more detailed discussions about birth processes in the following class session.
Topics reviewed will include general pregnancy information, while keeping some content suitable for a broader audience (i.e., G-rated).

Mention of how common births are:
- Average of seven babies born every second, highlighting the significance of birth in society.

Instructor shares personal experiences with parents, including:
- Students who've witnessed multiple births in ambulance settings.
- Instructor: Zero births attended in the field but has been involved with miscarriages and other experiences related to labor.
- Births generally are uncomplicated but can have complications that medics must address.

Birth is a natural process; the instructor emphasizes it is not a disease but a normal occurrence.
Notable statistic: Approximately one-third of births are C-sections. Potential reasons include scheduling convenience for medical practitioners.
The instructor shares a personal story about their wife's C-section due to limb presentation in a preterm baby.
Discussion of the past experiences with OBs revealing different C-section rates.

A hypothetical case of a 38-year-old female post-delivery presenting symptoms:
- Symptoms: Headache, blurred vision, and abdominal pain.
- Possible conditions include eclampsia (high blood pressure after childbirth), a rare but possible condition postpartum.
- Focus on hypertensive symptoms post-delivery and understanding the implications for treatment.
- Discussion of magnesium administration, with the idea that it may be administered to prevent seizures should they arise due to eclampsia.

Expect significant physiological changes during pregnancy.
Students are encouraged to take notes as specific information may be tested.
Key hormonal changes:
- Estrogen and progesterone levels steadily increase during pregnancy, impacting various systems in the body.

Explanation of the ovulation cycle:
1. Ovulation occurs (day zero).
2. Sperm fertilizes the egg roughly 12–24 hours post-ovulation (day one) resulting in a zygote.
3. The zygote becomes a blastocyst over several days before implanting into the uterus on day five.
Discussion of what happens if implantation does not occur, leading to menstruation.

Pregnancy approximates 40 weeks, tracked from the last menstrual period.
Difference between total gestational time and fertilization time approximated at 38 weeks.
The role of human chorionic gonadotropin (hCG) in confirming pregnancy via tests.
- Promotes corpus luteum function to maintain estrogen and progesterone levels, preventing menstruation.

First Trimester (Weeks 1-13): Hormonal changes dominate, with hCG levels peaking.
Role of the placenta: It takes over hormone production as the pregnancy progresses, decreasing reliance on the corpus luteum.
Discussion on physiological changes during pregnancy:
- Changes in the size and functionality of the uterus, affecting fundal height as gestational age progresses.
Measurements in centimeters from symphysis pubis (roughly where the uterine neck begins, right above pubic bone) to fundus (top of uterus) indicates gestational age of baby. For example, at 20 weeks the measurement will roughly measure 20cm, while at 36 weeks it will measure 36 cm.

Increased blood volume by 30-50% to support maternal-fetal circulation.
Heart rate typically increases by about 20 beats/min.
Physiological anemia of pregnancy commonly occurs as plasma volume increases outstrips red blood cell production, leading to hematocrit dilution.

Expected decrease in blood pressure due to vascular dilation from progesterone.
Emphasis: High blood pressure during pregnancy is concerning and should not present normally.
Understanding of Supine Hypotensive Syndrome involves the position of the uterus affecting venous return.
- Emphasis on left lateral positioning during transport of pregnant patients in EMS.

Diaphragm pushed upward, altering breathing capacity, requiring adaptations.
Tidal volume and minute volume typically increase to support fetal oxygen delivery.

Smooth muscle relaxation leads to increased constipation risks; dietary management may include stool softeners.
Hormonal effects allow for instances of nausea and vomiting (morning sickness) which can vary in severity.

Hormonal changes promote breast tissue development and milk machinery generation in breast.
Increased vasculature can create sensations like fullness or tenderness.

Hormonal changes may lead to joint pain or the distinct waddling gait seen in later pregnancy stages.
Mood swings influenced by variations in hormonal response can lead to anxiety or depression symptoms.

Summary reinforces the incredible demands pregnancy places on the female body:
- Key points include blood volume increase, hormonal changes, urinary frequency, cardiovascular adjustments, and mood fluctuations.

Review of vital signs during pregnancy:
- Heart rate: Increases
- Respiratory rate: Increases (usually shallower)
- Blood pressure: Should decrease, returning to normal later in pregnancy.
Importance of understanding maternal history, including previous pregnancies, prenatal care, and the specific symptoms indicating labor onset.
Importance of compassion and sensitivity when interviewing pregnant patients; avoid assumptions about pregnancies based on appearance.