Pregnancy & Labor Flashcards
Pregnancy Induced Hypertension
Blood pressure increase of - 30 mm Hg systolic or - 15 mm Hg diastolic over prepregnancy values or
- BP of 140/90 after 20 weeks if previous
BP is unknown
Chronic HTN
- BP > 140/90 before 20 wk gestation
or
• Known previous hypertension
Pre-Eclampsia
- BP increase as with PIH, plus proteinuria
and edema - Proteinuria = 0.1 gm/liter in a random
specimen or 0.3 gm in a 24 hour specimen - Edema may manifest as clinical swelling
or rapid weight gain
Severe Pre-Eclampsia
• BP of 160 mm Hg systolic or 110 mm Hg diastolic • Proteinuria OF 5 gm or more in 24 hr • Oliguria (500 ml or less in 24 hr) • Cerebral or visual disturbances • Epigastric pain • Pulmonary edema or cyanosis • Impaired liver function of unclear etiology • Thrombocytopenia
HELLP Syndrome
• Hemolysis
• Elevated Liver enzymes
• Low Platelets
Eclampsia
- Eclampsia is the presence of seizures
not attributable to another cause
• High fetal mortality
• Significant maternal morbidity
Treatment of PIH/Pre-eclampsia
- Delivery is the definitive treatment. • Delivery is indicated for a woman – at term with PIH – preterm with severe disease – Immediate if oliguria, renal failure, or HELLP syndrome, regardless of fetal gestation
Alpha Methyldopa
- Acts as a false neurotransmitter • Most extensively used antihypertensive medication in pregnancy • Fetal safety is well documented • Watch for orthostatic hypotension
Hydralazine
- Vasodilator
• Watch for reflex tachycardia
Musculoskeletal change during pregnancy
Lordosis: more curvature of the spine to accommodate the size and weight of the fetus
Heigh of Fundus at 20 weeks gestation
at the height of the belly button/umbilicus
Morning sickness (time of onset and cause)
- usually beginning about 4-8 weeks until about 14-16 weeks
- This may be related to sensitivity to human chorionic gonadotrophin levels (hCG)
- High levels of progesterone cause smooth muscle relaxation which decreases the tone and motility of the gastrointestinal (GI) system (good for absorbing nutrients, but bad for nausea)
“physiologic anemia” of pregnancy
- Aldosterone controls plasma volume increase
- Erythropoetin controls increase of red blood cells
- Plasma volume increase begins earlier than red blood cell volume increase
Uterine Phases of Parturition
Phase 0 - Relaxation phase - contractile unresponsiveness
- uses a lot of inhibitors, especially PROGESTERONE
Phase 1 - Preparation for labor
- ESTROGEN
Phase 2 - Processes of labor - three stages of labor
Stimulation: PROTSTGLANDINS AND OXYTOCIN
Phase 3 - Parturient recovery - uterine involution, breast feeding, restoration of fertility
Oxytocin
- 9 amino acid peptide synthesized in the HYPOTHALAMUS and released from the POSTERIOR PITUITARY
- Short ½ life, 3 to 6 minutes
- Important in maintaining uterine contractions postpartum
- Infusions of oxytocin cause contractions and can induce labor
Cervical Effacement
- the progressive thinning of the cervix from about 2 cm in thickness to paper thin.
- The cervical substance is drawn upward to become a part of the lower uterine segment.
Cervical Dilatation
- The cervix must dilate to 10 centimeters to accommodate the diameter of a full-term fetus’s head
3 Stages of Labor
First Stage of Labor
- begins when uterine contractions are of sufficient frequency, intensity and duration to bring about effacement and progressive dilatation of the cervix
- further divided into latent and active phases (acceleration, maximum slope, deceleration)
Second Stage of Labor
- begins when dilatation of the cervix is complete and ends with delivery of the fetus
Third Stage of Labor
- Interval between delivery of fetus to delivery of placenta.
- During this stage the placenta separates and is expelled
Seven Cardinal Movements for Delivery
- Engagement: the BPD descends to the level below the plane of the pelvic inlet
- Descent: Fastest during Deceleration phase of stage 1
- Flexion: Flexion of the fetal chin onto the fetal chest occurs passively as the descending head meets resistance
- Internal Rotation: baby rotates so more “up and down”
- Extension
- External Rotation (Restitution)
- Expulsion
“Every Delivery Feels IckyEEE”
Reasons for performing a cesarean delivery
- fetal malpresentation
- nonreassuring fetal heart rate tracing during labor
- arrest of labor
Pre-Term Birth & Risk Factors
– Infants delivered <259 days post conception
Major risk factors for preterm birth (but EVERY PREGNANCY IS AT RISK): – Prior history of preterm birth – Multifetal gestation – Bleeding after the 1st trimester – Low maternal body mass index (BMI)
Initiating Factors: - Infection • Vascular – ischemia/hemorrhage • Stress-nutrition • Uterine over distension • Cervical disease • Progesterone deficiency • Abnormal allogenic recognition • Allergy • Unknown
Low birth weight (LBW)
<2,500 gm at birth regardless of gestational age
Very low birth weight (VLBW)
<1,500 gm at birth
Premature rupture of membranes (PROM)
vs.
Preterm premature rupture of membranes
(PPROM)
PROM: rupture of membranes before the onset of labor
PPROM: rupture of membranes before 37 weeks
gestation, before the onset of labor
How to Diagnose Pre-Term Labor
- Fibronectin is a glycoprotein produced by a variety of cell types and is thought to have a role in intracellular adhesion in relation to maintenance of adhesion of the
placenta to the decidua. - Fetal fibronectin detected in cervical secretions may signal impending preterm birth; however, there is a
significant false positive rate. - The ABSENCE of fetal fibronectin in cervical secretions is more useful clinically because these patients can be potentially treated less agressively.
Maternal Indications for Preterm
Delivery
- Preeclampsia
• Renal disease
• Cardiac disease
Fetal Indications for Preterm Delivery
Unfavorable intrauterine environment where
risks of in utero damage or stillbirth are
more significant than the risks of
prematurity, e.g.
– Intrauterine growth restriction
– Poorly controlled maternal diabetes mellitus
– Placenta previa
– Placental abruption
Antenatal Corticosteroids reduce the risk of:
- respiratory distress syndrome
– intraventricular hemorrhage
– necrotizing enterocolitis
– patent ductus arteriosus
