Medical Complications of Pregnancy UNC School of Medicine Obstetrics and Gynecology Clerkship Case Based Seminar Series Objectives Identify the following medical and surgical conditions in pregnancy and discuss the potential impact of the conditions on the gravid patient and the fetus/newborn, as well as the impact of pregnancy (if any) on each condition, and appropriate initial evaluation: Anemia Endocrine disorders (Diabetes mellitus, Thyroid disease) Cardiovascular disease Hypertension Pulmonary disease Renal disease Gastrointestinal disease Neurologic disease Autoimmune disorders Alcohol, tobacco, and substance abuse Surgical abdomen Infectious disease, including: Syphilis, TORCH, Group B Streptococcus, Hepatitis, HIV, HPV, Parvovirus, Varicella ANEMIA Anemia • In pregnancy, plasma volume expands proportionally greater than that of RBC mass • Because Hct reflects proportion of blood made up primarily of RBCs, Hct demonstrates a “physiologic” decrease during pregnancy • Defined as – Hct <33% for first and third trimesters – Hct <32% for second trimester Anemia • Iron deficiency: – Pregnancy results in increased iron requirements – Standard American diet and endogenous stores of many women are not sufficient to provide for increased requirements – Recommendation: 27mg Fe daily supplementation for pregnant women Anemia • Other anemias – Sickle cell disease – Thalassemias – Hereditary hemolytic anemias Anemia • Fetal outcomes such as preterm labor, IUGR and LBW are more common in women with hemoglobinopathies – except those with sickle cell trait • Antenatal assessment of fetal well-being and growth is important part of managing these patients Anemia • Evaluation – Routine prenatal labs: • Hematocrit or hemoglobin to screen for anemia • Mean corpuscular volume (MCV) to screen for thalassemia (MCV <80 fL in the absence of iron deficiency suggests thalassemia and further testing with hemoglobin electrophoresis is indicated) – Further testing for thalassemias and/or other hemoglobinopathies based on parent history, family history, ethnic origin ENDOCRINE DISORDERS Gestational diabetes Pathophysiology Placental hormone increases insulin resistance Human placenta lactogen (hPL) Disease presents like Type II diabetes, but for the first time in pregnancy Diagnosis One hour 50gm glucose screening test (O‘Sullivan) (nl < 140mg/dl) 3-hour GTT (fasting < 105, 1-hour < 190, 2-hour <165. 3-hour < 145mg/dl) Diabetes: Complications Pregestational Maternal • • • • • • Accelerated retinopathy or nephropathy More difficult to control glucose levels • DKA, hyperosmolar coma • Hypoglycemia Pregnancy induced hypertension/preeclampsia Increased risk of infection Gestational • Gestational • Preeclampsia Fetal Neonatal • • • • • • • • Spontaneous abortion Congenital anomalies • Congenital heart disease (VSD, transposition of the great arteries) • Neural tube defects • Caudal regression Macrosomia Polyhydramnios Preterm birth Stillbirth (IUFD) Intrauterine growth restriction (IUGR) • • • • • Morbidity from preterm delivery Injury from traumatic delivery secondary to macrosomia Hypoglycemia, hypocalcemia, hyperbilirubinemia Management of congenital anomalies Respiratory distress syndrome • • • Macrosomia Intrauterine growth restriction (IUGR) Stillbirth (IUFD) Injury from traumatic delivery secondary to macrosomia Hypoglycemia, hypocalcemia, hyperbilirubinemia Respiratory distress syndrome Gestational diabetes Management Tight control essential Diet – 30-35 kcal/kg ideal body weight ADA diet Glucose testing - fasting and 2-hours following meals FBS <105mg/dl 1-hour PP <130mg/dl Thyroid Disease • Hyperthyroidism – May suppress fetal and neonatal thyroid function – Has been associated with fetal goiter – Thyroid storm – high risk of maternal heart failure • Hypothyroidism – Maternal thyroxine requirements increase during pregnancy – Adjust levels q4 wks and then check TSH each trimester CARDIOVASCULAR DISEASE Cardiovascular Disease • Pregnancy results in ~40% increase in cardiac output • The risks for mother and fetus are therefore often profound for women with pre-existing cardiac disease; ex: – Rheumatic heart disease – Acquired infectious valvular disease Cardiovascular Disease • Fetal complications – Fetuses of patients with functionally significant cardiac disease are at increased risk for LBW and prematurity – Patient w/ congenital heart disease is 1-5% more likely to have a fetus with a congenital heart disease as well – High rate of fetal loss in women with rheumatic heart disease EvaluationDisease Cardiovascular • Evaluation – Ideally, women with cardiac disease should have preconception care directed at maximizing cardiac function and counseling regarding risks that their particular disease poses in pregnancy – Serial evaluation of • Maternal cardiac status • Fetal well-being and growth HYPERTENSION Hypertension Classification: Chronic – HTN present before 20th week of pregnancy Gestational – HTN that develops after 20 wks gestation in the absence of proteinuria and returns to normal postpartum Preeclampsia – HTN with proteinuria and edema after 20 wks gestation Eclampsia – additional presence of convulsions in a woman with preeclampsia that is not explained by a neuro disease HELLP Syndrome – presence of hemolysis, elevated liver enzymes and low platelets Hypertension • Pathophysiology: – Predominant pathophysiologic finding is maternal vasospasm – Potential contributors: • • • • Endothelial damage Increased platelet activation and consumption Increased TXA2 and PGI2 Decreased NO Hypertension • Maternal complications: – Liver dysfunction – Renal insufficiency – Coagulopathy – Convulsions Hypertension • Potential Fetal Complications – IUGR – PTB – Abruption • Studies to evaluate: Ultrasound – Fetal weight and growth assessment – Amniotic fluid volume – Umbilical artery dopplers Hypertension • Evaluation: – Routine measurement of BP – Compare weight to pregravid weight and previous weights during pregnancy to monitor for rapid or excessive gain – Note excessive, persistent edema (general peripheral edema is normal) – Labs • CBC, platelets • LFTs • Serum Cr PULMONARY DISEASE Pulmonary Disease • Asthma – restrictive airway disease • Effects of pregnancy on asthma are variable – 1/3 patients improve – 1/3 worsen – 1/3 unchanged Pulmonary Disease • Women with mild-moderate asthma usually have excellent maternal and fetal outcomes • Suboptimal control of asthma during pregnancy may be associated with increased risk of – LBW – Prematurity Pulmonary Disease • Routine evaluation of pulmonary function in pregnant women w/ persistent asthma is recommended • Consider serial ultrasounds starting at 32 weeks for women w/ moderate-severe asthma during pregnancy RENAL DISEASE Renal Disease • UTIs • Pre-existing renal disease UTIs • Common in pregnancy • Aysmptomatic bacteruria is more likely to lead to cystitis and pyelonephritis in pregnant women – Pregnancy associated urine stasis – Glycosuria – ↑ urine pH • Urine culture should be obtained at first prenatal visit Pyleonephritis • One of the most common medical complications in pregnancy requiring hospitalization • Associated with↑increased risk of preterm labor – E. coli produces phospholipase A promotes prostaglandin synthesis ↑ uterine activity • Treat with IV hydration and antibiotics Pre-Existing Renal Disease • Women with significant pre-existing renal disease (chronic renal failure or transplant) should be advised of risks involved in pregnancy during preconception counseling • Patients with mild renal insufficiency generally have uneventful pregnancy Pre-Existing Renal Disease • Patients with moderate-severe disease are at risk for worsening renal function, proteinuria and associated hypertensive complications of pregnancy • Women with chronic renal disease also have increased incidence of IUGR and need serial assessments of fetal well being and growth GASTROINTESTINAL DISEASE GI Disease • Nausea and vomiting of pregnancy (NVP) – typically begins ~4-8 wks gestation and stops by 14-16 wks – Related to ↑ progesterone and hCG, smooth muscle relaxation of the stomach • Hyperemesis gravidarum – severe NVP which results in weight loss, ketonemia or electrolyte imbalance • GERD – symptoms become more pronounced as pregnancy advances – Due to ↑ intraabdominal pressure GI Disease • Complications for mom or baby are rare • Evaluation for mom with persistent vomiting: – – – – – – Weight Orthostatic BPs Serum electrolytes Urine ketones Thyroid function tests Ultrasound to exclude gestational trophoblastic disease and multiple gestation, both of which are associated with hyperemesis NEUROLOGIC DISEASE Epilepsy • Majority of women with epilepsy have normal pregnancy • Typically there is not an increased frequency of seizures during pregnancy Epilepsy • Small association with LBW, lower Apgar scores, preeclampsia, bleeding, placental abruption, and prematurity • Increases risk of congenital malformations in fetus exposed to phenytoin, valproic acid, phenobarbital and carbamazepine • Risks to fetus of actual seizures - hypoxia, abruption, or miscarriage due to maternal trauma sustained during a seizure; although few studies have been done to assess AUTOIMMUNE DISORDERS SLE • Prognosis for mom and baby is best when SLE has been quiescent for at least 6 months prior to the pregnancy • Should be seen by OB who is experienced in management of high risk pregnancies • Exacerbation of disease can occur throughout all three trimesters and even in postpartum period SLE • Women with SLE have increased risk of preeclampsia • Significant risk of fetal loss in women with hypertension, active lupus, lupus nephritis, hypocomplementemia, ↑ anti-DNA antibodies, ↑ aPL or thrombocytopenia • Mothers should be assessed for disease activity at least once per semester – more if they have active lupus ALCOHOL, TOBACCO AND SUBSTANCE ABUSE Alcohol Use • Leading preventable cause of mental retardation, developmental delay and birth defects in the fetus • Greatest risk – exposure during first trimester • No established safe level of consumption Tobacco Use • Risks to fetus – IUGR, LBW, fetal death • Safety of nicotine replacement products in pregnancy has not been documented Substance Abuse • Illicit drugs reach fetus via placental transfer or reach newborn through breast milk • Opiate-exposed fetus – may have withdrawal symptoms in utero or after birth • Universal specimen screening is not recommended, however all women should be questioned about and counseled if appropriate about past and present use of alcohol, nicotine and other drugs SURGICAL ABDOMEN Surgical Abdomen • Surgical treatment of pregnancy women should consider maternal and fetal health needs • Don’t avoid radiographic or other studies because woman is pregnant, but exercise caution • Monitor fetal heart tones during surgery to the extent possible • Avoid placing patient fully supine if possible – place in decubitus lateral tilt to prevent supine hypotensive syndrome INFECTIOUS DISEASES ToRCHeS Infection Toxoplasma Transmission Maternal Disease Cat feces, Usually asymptomatic, sometimes undercooked meat lymphadenopathy Rubella Respiratory droplets CMV Sexual contact, Usually asymptomatic, sometimes organ transplants mono-like illness HIV HSV Syphillis Rash, lymphadenopathy, arthritis Sexual contact Variable, depending on CD4 count Skin or mucous Usually asymptomatic; herpetic membrane contact lesions Sexual contact Primary - chancre, Secondary disseminated rash, Tertiary cardiac/neurologic disease Neonatal Disease Triad - chorioretinitis, hydrocephalus, intracranial calcifications Triad - PDA (or pulmonary artery hypoplasia), cataracts, deafness; +/blueberry muffin rash Hearing loss, seizures; most asymptomatic; some w/ same triad as toxoplasma Recurrent infxns, chronic diarrhea Temporal lobe encephalitis (seizures), herpetic lesions Stillbirth, hydrops fetalis If child survives - facial abnormalities (notched teeth, saddle nose, short maxilla), saber shins, snuffles (bloody nasal discharge) GBS • Asymptomatic lower genital tract colonization is common • Without treatment, GBS sepsis can occur • Infection of newborn – septicemia, septic shock, pneumonia or meningitis • Universal screening at 35-37 wks if positive, give antibiotic prophylaxis in labor HIV • All women exhibit absolute decline in CD4 counts in pregnancy – thought to be 2/2 hemodilution • Perinatal transmission w/o prophylaxis is ~25% • With Zidovudine monotherapy – transmission ~8% • Combination therapy and undetectable viral load – transmission ~1-2% • Universal, voluntary HIV screening should be part of standard prenatal labs HPV • Genital wart lesions often increase in size and area during pregnancy due to relative immune suppression • If extensive – c/s delivery may be necessary • Transmission to infant is rare, but if occurs – manifests as laryngeal papillomatosis – c/s delivery does not prevent transmission Parvovirus • Can cause devatsating fetal outcomes – SAB, fetal nonimmune hydrops fetalis, death • Maternal immune status can be determined by serologic testing – IgM recent infection, IgG past infection and immunity – Routine serologic testing not recommended – Exposed pregnant women should be offered B-19 specific IgM and IgG serologic testing • If IgM + confirmed – serial ultrasounds starting at 10 wks to look for evidence of hydrops, placentomegaly and growth disturbances • If hydrops doesn’t develop, long-term outcomes are good Hepatitis • Hepatitis A – Vaccination safety during pregnancy has not been established – HAV IG is effective for both pre and post-exposure prophylaxis and can be used during pregnancy • Hepatitis B – Routine testing for HBsAg - if neg w/ risk factors for HBV infection – offer vaccination during pregnancy – All infants receive Hep B vaccine – Infants of mothers who are HBsAg pos should get vaccine and HBIG w/in 12 hrs of birth Hepatitis • Hepatitis C – Routine screening is not recommended – Co-infection with HIV is associated with a higher risk of vertical transmission of HCV – No known preventative measures to reduce risk of mother to child transmission • Hepatitis D – Infection can only occur along with Hep B infection – Vertical transmission has been documented but is rare • Hepatitis E – Associated with higher rates of fulminant disease and mortality in pregnant women – Risk of vertical transmission is low Bottom Line Concepts Maternal medical or surgical conditions can complicate the course of a pregnancy and/or can be affected by pregnancy Important to understand: Effect of pregnancy on natural course of disorder Effect of disorder on pregnancy Change in mgmt of the pregnancy and disorder caused by their coincidence Screening for and preventing infectious diseases is an integral part of routine prenatal care Many infectious diseases can have devastating effects for mother, infant or both References and Resources APGO Medical Student Educational Objectives, 9th edition, (2009), Educational Topic 17 (p36-37). Beckman & Ling: Obstetrics and Gynecology, 6th edition, (2010), Charles RB Beckmann, Frank W Ling, Barabara M Barzansky, William NP Herbert, Douglas W Laube, Roger P Smith. Chapter 14, 15, 16 (p151182). Hacker & Moore: Hacker and Moore's Essentials of Obstetrics and Gynecology, 5th edition (2009), Neville F Hacker, Joseph C Gambone, Calvin J Hobel. Chapter 14, 16 (p173-182, 191-218).