Pregnancy

From Anvita Health Wiki

Contents 1 More Specific Terms 2 Introduction 3 Laboratory 4 Management 5 More General Terms 6 Additional Terms 7 References

More Specific Terms

• multiple gestation (multiple pregnancy)

Introduction

• Childbirth generally occurs ~ 38 weeks after conception or ~ 40 weeks from the last normal menstrual period. Physiolology:
  

• Cardiology
• hemodynamic changes:

• increased plasma volume (1100-1500 mL)
• increased red cell mass (300 mL)
• increased cardiac output
• heart rate increase 20-30% (< 100/min)
• blood pressure

• decreases soon after conception
• reaches a nadir in 20 weeks

• hypertension affects 10% of pregnant women

• blood pressure (BP) > 140/90
• increase of systolic BP of > 30 mm Hg
• increase of diastolic BP of > 15 mm Hg

• auscultation

• systolic ejection murmur in pulmonic area, not more than III/VI is a normal finding during pregnancy
• 3rd heart sound (S3) is common in pregnancy; S4 heart sound is pathologic
• grade 1-2/6 systolic murmur normal
• grade 3/6 systolic murmur or any diastolic murmur is pathologic
• diastolic rumble should raise suspicion of mitral stenosis

• absolute contraindications to pregnancy

• Marfan syndrome with dilated aortic root

• increased risk of dissection & rupture due to hormonal- induced softening of connective tissue
• unpredictable risk of dissection & rupture, regardless of aortic size

• Eisenmenger's syndrome (50% maternal mortality)
• primary pulmonary hypertension
• symptomatic aortic stenosis
• symptomatic mitral stenosis
• symptomatic dilated cardiomyopathy

• heart failure

• mild dyspnea on exertion is normal
• orthopnea, paroxysmal noctural dyspnea pathologic
• minimize activity to decrease cardiac output
• reduce sodium in diet
• minimize anemia: vitamin & iron supplements
• avoid ACE inhibitors, ARBs, aldosterone antagonists

• arrhythmias

• atrial premature contractions normal
• ventricular premature contractions normal
• atrial fibrillation, atrial flutter, ventricular tachycardia are pathologic
• cardioversion may be performed if necessary

• simultaneous monitoring of fetal heart

• surgery

• during 1st trimester associated with increased fetal loss
• percutaneous balloon valvuloplasty well tolerated

• aortic, mitral & pulmonary valvuloplasty
• lead shielding of fetus

• pharmceutical agents

• contraindicated

• captopril, phenytoin, warfarin, tetracycline

• drugs which cross placenta, but may be used safely

• digoxin, quinidine, procainamide, verapamil
• beta blockers

• monitor fetal growth
• may be associated with fetal growth retardation, neonatal bradycardia & hypoglycemia

• delivery

• average blood loss

• 500-800 mL with vaginal delivery
• 800 mL with cesarean section

• with each uterine contraction, 500 mL of blood is released into the circulation
• no need for antibiotic prophylaxis for uncomplicated vaginal delivery

• prosthetic valves

• most women of child-bearing age who need valve replacement receive bioprosthetic valves
• generally, they do not receive anticoagulation
• in pregnant women with mechanical valves, switch from warfarin to subcutaneous heparin
• heparin is associated with increased fetal loss

• Nephrology: ( Renal)

• renal enlargement (1 cm)
• dilatation of the renal calyces, pelvis & ureters

• features can resemble obstructive uropathy [2]

• 30-50% increase in glomerular filtration rate (GRR) & renal blood flow
• mean serum creatinine of 0.5 mg/dL, 0.8 mg/dL (max)
• mean urea nitrogen of 18 mg/dL, 26 mg/dL (max)
• intermittent glycosuria (< 1 g/day) independent of plasma glucose
• proteinuria

• normal < 300 mg/day, may be postural
• women with underlying renal insufficiency may have a significant increase in proteinuria during pregnancy associated with poorer fetal prognosis, not associated with any worsening of their renal disease [2]
• women with diabetes mellitus type-1 with microalbuminuria but normal renal function & blood pressure have pregnancy outcomes similar to the general population [2]

• increased uric acid secretion
• increased total body water (6-8 L) with osmostat resetting
• 50% increase in plasma volume
• increased ureteral peristalsis
• changes in sodium metabolism

• hyponatremia not uncommon
• renal sodium retention

• hypertension, proteinuria, or elevated serum creatinine during the first antepartum visit suggests chronic glomerulonephritis
  

• Endocrine:

• increased plasma levels of

• renin
• angiotensin II
• aldosterone
• cortisol
• estrogens
• prostaglandins E2 & I2
• progesterone

• insensitivity to pressor effects of:

• angiotensin II
• norepinephrine

• progesterone counteracts K+ excreting effects of aldosterone
• 30-50% increase in requirement for thyroxine

• similar increase in requirement for iodine [2]
• subclinical hypothyroidism may adversely affect outcome [6]
  

• Immunology:

• 3rd trimester is associated with immunosuppression
• defects in neutrophil chemotaxis
• defect in T-cell mediated cellular immunity
• risk of disseminated Herpes zoster
• risk of disseminated coccidioidomycosis
  

• Hematology:

• anemia

• decrease in hemoglobin as low at 10 mg/dL
• increase in plasma volume (1100-1500 mL)
• lesser increase red cell mass (300 mL)
• iron deficiency generally involved

• iron preferentially routed to fetus
• 1000 mg of iron generally required per pregnancy

• blood loss
• fetal requirements

• aplastic anemia may be associated with pregnancy

• resolves with termination of pregnancy
• may recur with subsequent pregnancy

• sickle cell disease

• increased maternal mortality
• increased fetal morbidity
• prophylactic transfusion is NOT of benefit

• thrombocytopenia

• mild gestational thrombocytopenia (> 75,000/ uL) in 8.3%

• generally develops in 3rd trimester
• no specific treatment needed

• chronic immune thrombocytopenic purpura ( ITP)

• may be worsened by pregnancy
• IgG of ITP crosses placenta
• prednisone is 1st line
• IV immune globulin if refractory to prednisone

• HELLP syndrome

• hemorrhagic disorders

• factor VIII autoantibodies
• factor VIII- vWF complex increases in 2nd trimester with a rapid decrease post-partum

• thrombotic disorders

• pregnancy should be considered a hypercoagulable state

• concentration of procoagulant factors increase progressively during pregnancy
• protein S & fibrinolytic activity decrease
• coagulation cascade may be activated in the placenta
• increased venous stasis in lower extremities
• labor & delivery, especially C-section increase risk of thrombosis

• normal levels of plasma fibrinogen in the 3rd trimester of pregnancy is about twice the non-pregnant state
• disseminated intravascular coagulation ( DIC)

• most common thrombotic disorder in pregnancy
• abruptio placenta is the most common cause of DIC
• amniotic fluid embolism
• intrauterine fetal death
• saline- induced abortion
• septic abortion
• frequent association with fatty liver of pregnancy

• placental tissue factor or activated clotting factors entering the mother's circulation may trigger DIC
  

• General:

• peripheral edema in 35-85%, pulmonary edema is pathologic
• higher risk for stillbirth > 40 years of age
• risk of genetic abnormalites accelerates after 35 years of age

Laboratory

• urinalysis for asymptomatic bacteriuria (all women)
• complete blood count for iron deficiency anemia

• workup anemia

• hepatitis B serology
• syphilis serology [2]
• blood type & screen
• serum TSH

Management

• folic acid 0.4-0.8 mg QD

• begin at least 1 month prior to conception & continue for 2-3 months after delivery

• vaccinations

• Tdap after 20 weeks gestation (unless previously vaccinated)

• follow with dT q 4 weeks x 2 if not previously vaccinated for tetanus [9]

• influenza vaccine can be given any trimester [9]

More General Terms

• reproduction

Additional Terms

• abortion
• alcohol during pregnancy
• fetus
• labor & delivery (childbirth, parturition)
• medications contraindicated during pregnancy
• medications during pregnancy
• miscarriage
• pregnancy category
• pregnancy disorder; obstetric disorder
• pregnancy test
• prenatal care

References

1. Mayo Internal Medicine Board Review, 1998-99, Prakash UBS (ed) Lippincott-Raven, Philadelphia, 1998, pg 49-50, 619
2. Medical Knowledge Self Assessment Program (MKSAP) 11, 15 American College of Physicians, Philadelphia 1998, 2009
3. Prescriber's Letter 11(9): 2004 Management of Hypothyroidism in Pregnancy Detail-Document#: [1] (subscription needed) [2]
4. Reddy UM et al, Maternal age and the risk of stillbirth throughout pregnancy in the United States. Am J Obstet Gynecol 2006, 195:764 PMID: [3]
5. Wolff T et al Folic acid supplementation for the prevention of neural tube defects: an update of the evidence for the U.S. Preventive Services Task Force. Ann Intern Med. 2009 May 5;150(9):632-9. PMID: [4] U.S. Preventive Services Task Force. Folic acid for the prevention of neural tube defects: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2009 May 5;150(9):626-31. PMID: [5]
6. Negro R et al. Increased pregnancy loss rate in thyroid antibody negative women with TSH levels between 2.5 and 5.0 in the first trimester of pregnancy. J Clin Endocrinol Metab 2010 Sep; 95:E44 PMID: [6]
7. Pregnancy: NIH Institute and Center Resources [7]
   - Managing Asthma During Pregnancy: Recommendations for Pharmacologic Treatment--Update 2004 [8]
8. Prescriber's Letter 18(12): 2011 Use of Influenza and Pertussis Vaccines in Pregnancy Detail-Document#: [9] (subscription needed) [10]
9. National Guideline Clearinghouse
   - Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society clinical practice guideline. ngc-guideline: [11]
   - Growth disturbances: risk of intrauterine growth restriction. American College of Radiology ngc-guideline: [12]
   - Thromoembolism in pregnancy ngc-guideline: [13]
   - Ultrasound scanning during pregnancy Finnish Medical Society Duodecun ngc-guideline: [14]
   - Chronic hypertension in pregnancy ngc-guideline: [15]
   - Intrapartum fetal heart rate management. ngc-guideline: [16]
   - Multiple gestations. American College of Radiology ngc-guideline: [17]
   - Management of postterm pregnancy American College of Obstetricians and Gynecologists ngc-guideline: [18]
   - Practice management guidelines for the diagnosis and management of injury in the pregnant patient: the EAST Practice Management Guidelines Work Group. (Eastern Association for the Surgery of Trauma) ngc-guideline: [19]
   - Cervical insufficiency. American College of Obstetricians and Gynecologists ngc-guideline: [20]
   - Nausea and vomiting of pregnancy. American College of Obstetricians and Gynecologists ngc-guideline: [21]
   - Multiple gestation: complicated twin, triplet, and high-order multifetal pregnancy. American College of Obstetricians and Gynecologists ngc-guideline: [22]
   - Use of psychiatric medications during pregnancy and lactation. American College of Obstetricians and Gynecologists ngc-guideline: [23]
   - Improving the nutrition of pregnant and breastfeeding mothers and children in low-income households. National Institute for Health and Clinical Excellence (NICE) ngc-guideline: [24]
   - Guidelines for the management of pregnancy at 41+0 to 42+0 weeks. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [25]
   - Obstetrical complications associated with abnormal maternal serum markers analytes. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [26]
   - Rubella in pregnancy. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [27]
   - Pre-conceptional vitamin/folic acid supplementation 2007: the use of folic acid in combination with a multivitamin supplement for the prevention of neural tube defects and other congenital anomalies. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [28]
   - Assessment of gravid cervix. American College of Radiology. ngc-guideline: [29]
   - Critical care in pregnancy. American College of Obstetricians and Gynec ngc-guideline: [30]
   - Screening for syphilis infection in pregnancy: U.S. Preventive Services Task Force reaffirmation recommendation statement. ngc-guideline: [31]
   - Eating disorders during pregnancy and postpartum. University of Arkansas for Medical Sciences, ANGELS (Antenatal & Neonatal Guidelines, Education and Learning System) ngc-guideline: [32]
   - Content of a complete routine second trimester obstetrical ultrasound examination and report. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [33]
   - Bariatric surgery and pregnancy. American College of Obstetricians and Gynecologists (ACOG) ngc-guideline: [34]
   - Screening for hepatitis B virus infection in pregnancy: U.S. Preventive Services Task Force reaffirmation recommendation statement. United States Preventive Services Task Force ngc-guideline: [35]
   - Immunization in pregnancy. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [36]
   - Diagnosis and management of injury in the pregnant patient (Eastern Association for the Surgery of Trauma) [37]
   - Inherited thrombophilias in pregnancy. American College of Obstetricians and Gynecologists (ACOG) ngc-guideline: [38]
   - VA/DoD clinical practice guideline for management of pregnancy. ngc-guideline: [39]
   - Cytomegalovirus infection in pregnancy. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [40]
   - Obesity in pregnancy. Society of Obstetricians and Gynaecologists of Canada ngc-guideline: [41]
   - Pregnancy and complex social factors. A model for service provision for pregnant women with complex social factors. National Collaborating Centre for Women's and Children's Health ngc-guideline: [42]
   - Maternal collapse in pregnancy and the puerperium. Royal College of Obstetricians and Gynaecologists (RCOG) ngc-guideline: [43]
   - Reduced fetal movements. Royal College of Obstetricians and Gynaecologists (RCOG) ngc-guideline: [44]
   - Best evidence statement (BESt). Exposure of pregnant healthcare workers to radioisotope Neurolite teratogenic risks. Cincinnati Children's Hospital Medical Center ngc-guideline: [45]
   - Maternity leave in normal pregnancy. ngc-guideline: [46]

pregnancy (gestation)