OB Exam 1 Bitch

Follicular Phase

Days 1-13 of menstrual cycle

Ovulation

Day 14 of menstrual cycle

Luteal Phase

Days 15-28 of menstrual cycle, endometrial re-building

Luteinizing Hormone (LH)

• Begins the cycle

• When rises, stimulates follicle to produce estrogen

• Surge establishes the corpus luteum

• Estrogen and progesterone from corpus luteum suppress LH output

Corpus Luteum

• Temporary, hormone producing structure that forms in the ovary after egg releases during ovulation

• Produces estrogen and progesterone

• Suppress LH output

Estrogen

• Increases steadily throughout PG

• Sensitizes uterus for labor

• Stimulates uterine growth and blood flow

Progesterone

• Pro-pregnancy

• Maintain PG

• Prevents pre-term labor (PTL) and contractions (CTX)

• Supports fetal and placental growth

• Relaxed uterus

• Rises 10x in pregnancy

Human Chorionic Gonadotrophic (hCG)

• Rise after conception

• Signals cease menstruation

• Thickens uterine lining

• Hormone detected on PG test

Human Placental Lactogen (hPL)

• Released by placenta

• Takes over hCG

• Regulated metabolism, builds insulin resistance

• Prep for breastfeeding

Ductus Venous

Connects the umbilical vein to the inferior vena cava (bypasses the liver)

Ductus Arteriosus

Connects the main pulmonary artery to the aorta (bypasses lungs)

Foramen Ovale

Anatomical opening between the right and left atrium (bypasses right ventricle)

Fetal Development

• 3-8 weeks: Major organs, neural tube during week 4

• 8-12 weeks: Fetus develops external genitalia, fingers and toes

• 14 weeks: $ex can be visually identified

• 16-20 weeks: Typically, pregnant woman can feel the fetus moving

• 19-24 weeks: Vernix, sucks thumb/swallow, eyebrows/lashes, makes meconium

• 24 weeks: Fetus has a chance of survival

Stages of Fetal Development

• Zygotic stage: Fertilization of sperm and egg (conception)

• Blastocyst: Zygote divides into a solid ball of cells and attaches to uterus

• Embryonic stage: End of 2nd week through 8th week, basic structures of major body organs and main external features

• Fetal stage: Differentiation and structures specialize by end of eighth week until birth

Common Menstrual Disorders (Know S/Sx, Definition, and Nursing Management)

• Amenorrhea

• Dysmenorrhea

• Dysfunctional Uterine Bleeding (DUB)/Abnormal Uterine Bleeding (AUB) and different types

• Adenomyosis

• Endometriosis

• Polycystic Ovary Syndrome (PCOS)

• Premenstrual Syndrome (PMS)

• Premenstrual Dysmorphic Disorder (PMDD)

Placenta

• Supplies fetus with nutrients and oxygen

• Protects fetus from immune attack

• Remove waste products from fetus

Prolactin

Hormone to support milk production

Relaxin

Loosens pelvis joints for birth, however, loosens all joints in body.

Umbilical Cord

• One large vein and two small arteries

• Formed from amnion (layer of amniotic sac)

• Wharton jells surrounds the vein and arteries to prevent compression of cord

Amniotic Sac

• 2 layers (chorion, amnion)

• Seals off infection

Amniotic Fluid

• Helps maintain a constant body temperature for fetus

• Contains baby’s surfactant

• Cushions fetus from trauma

• Allows umbilical cord to be relatively free of compression

• Promotes fetal movement to enhance musculoskeletal development

Presumptive Indications of Pregnancy

• Amenorrhea

• N/V

• Fatigue

• Urinary frequency

• Breast and skin changes

• Vaginal and cervical color changes - Chadwick’s sign (Also probable indication of pregnancy)

• Fetal movement/quickening

Probable Indications of Pregnancy

Changes in Pelvic Organs:

• Goodell’s Sign - Softening of cervix

• Chadwick’s sign (also presumptive)

• Hegar’s Sign - Softening and compressibility of lower uterine segment

Other Probable Indications:

• Skin pigmentation

• Palpated fetal outline or ballottement

• Pregnancy tests

• Abdominal/uterine enlargement

• Braxton Hicks contractions

Positive Indications of Pregnancy

• Auscultation of fetal heart sounds

• Fetal movement felt by examiner

• Visualization of fetus

Pregnancy Duration and Calculation

• First day of LMP (last menstrual period) - 3 months + 7 days

• Ultrasound can only be done to determine if done before 20 weeks, afterwards babies start growing at their own rate

Gravida

• A pregnant woman

• Gravida 1 (G1) First pregnancy

• Gravida 2 (G2) Second pregnancy

• …

Para

How many babies has a woman given birth to past 20 weeks (viable) regardless of living or stillborn?

G - #

Gravida - The current pregnancy

T - #

Term births - Number of pregnancies ending >37 weeks’ gestation, at term

P - #

Preterm births - The number of preterm pregnancies ending >20 weeks or viability but before completion of 37 weeks

A - #

Abortions - The number of pregnancies ending before 20 weeks or viability

L - #

Living Children - Number of children currently living

Recommended Pregnancy Weight Gain

• 1st Trimester - 3.5-5 lbs

• 2nd Trimester - 15 lbs

• 3rd Trimester - 15 lbs

Pregnancy Weight Gain Distribution

• Baby: 7-8 lbs

• Placenta: 1-2 lbs

• Uterus: 2 lbs

• Breasts: 1 lb

• Amniotic Fluid: 1 ½ - 2 lbs

• Blood Volume: 2 ½ - 3 lbs

• Fat: 5 lbs

• Extracellular Fluid: 4-7 lbs

BMI and Pregnancy Weight Gain

Low BMI: 35-45 lbs

Normal BMI: 25-35 lbs

High BMI: 15-25 lbs