108

USMLE Step 2 (Subject) / Obstetrics (Lesson)

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• Anemia of prematurity Etiology:- Imparied EPO production- Short red blood cell life span- Iatrogenic blood sampling Clinical features:- Usually asymptomatic- Tachycardia, apnea, poor weight gain Lab findings:- Low hemoglobin & hematocrit- Low reticulocyte count- Normocytic, normochromic red blood cells Treatment:- Minimize blood draws- Iron supplementation- Transfusions
• Postpartum urinary retention Inability to void ≥ 6 hours after vaginal delivery. Risk factors:- Primiparity- Regional neuraxial anesthesia → suppressed micturition reflex and decreased detrusor tone → bladder atony- Operative vaginal delivery- Perineal injury- Cesarean delivery Clinical features:- Small-volume voids or inability to void- Incomplete bladder emptying- Dribbling of urine Treatment:- Self-limited condition- Intermittent catheterization
• Pregnancy-related risks due to hypertension Maternal:- Superimposed preeclampsia- Postpartum hemorrhage- Gestational diabetes- Abruptio placentae- Cesarean delivery Fetus:- Fetal growth restriction- Perinatal mortality- Preterm delivery- Oligohydramnios
• Neural tube defects Types:- Encephalocele- Anencephaly- Spina bifida, myelomeningocele Risk factors:- Low folic acid intake- Methotrexate, antiepileptics- Diabetes mellitus- Prior pregnancy with neural tube defect Prenatal screening:- 2nd-trimester ultrasound- Maternal serum alpha-fetoprotein Prevention:- Average risk: 0.4 mg folic acid daily- High risk: 4 mg folic acid daily
• Tocolytics Indomethacin:- Cyclooxygenase inhibition- First-line tocolytic < 32 weeks- Side effects→ Maternal: Gastritis, platelet dysfunction→ Fetal: Oligohydramnios, closure of ductus arteriosus Nifedipine:- Calcium channel blocker- First-line tocolytic 32-34 weeks- Side effects: Tachycardia/palpitations, nausea, flushing, headache Terbutaline:- Beta agonist- Short-term tocolytic: inpatient use- Side effects: Tachycardia/arrhythmias, hypotension, hyperglycemia, pulmonary edema
• Complications of shoulder dystocia Fractured clavicle:- Clavicular crepitus/bony irregularity- ↓ Moro reflex due to pain on affected sign- Intact biceps & grasp reflexes Fractured humerus:- Upper arm crepitus/bony irregularity- ↓ Moro reflex due to pain on affected side- Intact biceps & grasp reflexes Erb-Duchenne palsy:- ↓ Moro & biceps reflexes on affected side- "Waiter's tip": Extended elbow, pronated forearm, flexed wrist & fingers- Intact grasp reflex Klumpke palsy:- "Claw hand": Extended wrist, hyperextended metacarpophalangeal joints, flexed interphalangeal joints, absent grasp reflex- Horner syndrome (ptosis, miosis)- Intact Moro & biceps reflexes Perinatal asphyxia:- Variable presentation depending on duration of hypoxia- Altered mental status (eg, irritability, lethargy), respiratory or feeding difficulties, poor tone, seizure
• Late- & post-term pregnancy Definition: - Late-term: ≥ 41 weeks gestation- Post-term: ≥ 42 weeks gestation Risk factors:- Prior post-term pregnancy- Nulliparity- Obesity- Age > 35 - Fetal anomalies (eg, anencephaly) Complications:Fetal/neonatal:- Macrosomia- Dysmaturity syndrome- Oligohydramnios- DemiseMaternal:- Severe obstetric laceration- Cesarean delivery- Postpartum hemorrhage Management:- Frequent fetal monitoring (eg, nonstress test)- Delivery prior to 43 weeks gestation
• Vaccines during pregnancy Recommended:- Tdap- Inactivated influenza- Rho(D) immunoglobulin High-risk patients:- Hepatitis B- Hepatitis A- Pneumococcus- Haemophilus influenzae- Meningococcus- Varicella-zoster immunoglobulin Contraindicated:- HPV- MMR- Live attenuated influenza- Varicella
• Preventing neonatal group B Streptococcus infection Universal screening: Rectovaginal culture at 35-37 weeks gestation Indications for intrapartum prophylaxis:- Prior delivery complicated by neonatal GBS infection- GBS bacteriuria or GBS UTI during current pregnancy (regardless of treatment)- GBS-positive rectovaginal culture- Unknown GBS status PLUS any of the following:→ < 37 weeks gestation→ Intrapartum fever→ Rupture of amniotic membranes for ≥ 18 hours Prophylaxis: - Best choice: Penicillin- Penicillin allergy but non-anaphylactic: Cefazolin- Penicillin allergy and anaphylactic: Clindamycin- Penicillin allergy and anaphylactic and resistent to clindamycin: Vancomycin
• Neonatal polycythemia Definition: Hematocrit > 65% in term infants Etiology:- Intrauterine hypoxia: maternal diabetes, hypertension, or smoking; IUGR- Erythrocyte transfusion: delayed cord clamping; twin-twin transfusion- Genetic/metabolic disease: hypothyroidism or hyperthyroidism; genetic trisomy (13, 18, 21) Clinical features:- Asymptomatic (most common)- Ruddy skin- Hypoglycemia, hyperbilirubinemia- Respiratory distress, cyanosis, apnea- Irritability, jitteriness- Abdominal distension Treatment:- Intravenous fluids- Glucose- Partial exchange transfusion
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• Eclampsia - Complications Maternal:- Placental abruption- Cerebellar hemorrhage, stroke- Acute renal failure- DIC- Acute respiratory distress syndrome (ARDS)- Retinal detachment- Maternal death Fetal:- Fetal growth restriction- Preterm birth- Seizure-induced fetal hypoxia- Fetal death
• Uterine rupture Risk factors:- Prior uterine surgery (eg, cesarean delivery, myomectomy)- Induction of labor/prolonged labor- Congenital uterine anomalies- Fetal macrosomia Etiology:- Uterine distention: → Delay in labor progression because of fetal malpresentation→ Fetal macrosomia and multiple gestations→ Overdose of oxytocin- Uterine scar/prior uterine surgery (e.g., C-section or myomectomy)- Traumatic rupture (e.g., iatrogenic or caused by an accident) Imminent rupture:- Severe abdominal pain- Increased contractions followed by hyperactive labor- Bandl's ring = Muscular ring that can be seen above the belly button due to the powerful contractions of the upper uterine segment.Uterine rupture:- Vaginal bleeding- Intraabdominal bleeding (hypotension, tachycardia)- Sudden pause in contractions- Fetal heart decelerations- Loss of fetal station- Palpable parts on abdominal examination Treatment: Laparotomy for delivery and uterine repair
• Septic pelvic thrombophlebitis Risk factors:- Cesarean delivery- Pelvic surgery- Endometritis- Pelvic inflammatory disease- Pregnancy- Malignancy Pathophysiology:- Hypercoagulability - Pelvic venous dilation- Vascular trauma- Infection Presentation:- Fever unresponsive to antibiotics- No localizing signs/symptoms- Negative infectious evaluation- Diagnosis of exclusion Treatment:- Anticoagulation- Broad-spectrum antibiotics
• Intrahepatic cholestasis of pregnancy Due to increased estrogen and progesterone levels that cause hepatobiliary tract stasis and decreased bile excretion. Clinical features:- Develops in 3rd trimester- Jaundice- Generalized pruritus that is worst on the hands & feet- No associated rash- Right upper quadrant pain Lab findings:- ↑ Total bile acids (cholic acid and chenodeoxycholic acid): > 10 µmol/L- ↑ Transaminases: < 2x normal- ↑ ALP- ↑ Direct bilirubin Management:- Delivery at 37 weeks gestation- Ursodeoxycholic acid- Antihistamines Obstetric risks:- Intrauterine fetal demise- Preterm delivery- Meconium-stained amniotic fluid- Recurrence in following pregnancies (40-60%) Prognosis: fully reversible postpartum
• Acute fatty liver of pregnancy A rare disorder most commonly in the third trimester Pathophysiology: dysfunction of fatty acid β-oxidation Clinical features:- Sudden onset of jaundice- Nausea, vomiting- Right upper quadrant/epigastric pain- Coagulopathy with an increased risk of disseminated intravascular coagulation (DIC) - Hypoalbuminemia → ascites- Complications: Acute liver failure Laboratory findings:- ↑ Aminotransferases (2-3x normal)- ↑ WBC, ↓ platelets- Profound hypoglycemia- ↑ Bilirubin- Liver synthesis parameters: ↓↓ clotting factors , ↓↓ Cholinesterase Management: Immediate delivery
• Causes of hyperandrogenism in pregnancy Placental aromatase deficiency:- No ovarian mass- High maternal & fetal virilization risk- Resolution of maternal symptoms after delivery Luteoma:- Solid, unilateral/bilateral ovarian masses- Moderate maternal virilization risk; high fetal virilization risk- Spontaneous regression of masses after delivery Theca lutein cyst:- Cystic, bilateral ovarian masses- Moderate maternal virilization risk; low fetal virilization risk- Spontaneous regression of masses after delivery Sertoli-Leydig tumor:- Solid unilateral ovarian mass- High maternal & fetal virilization risk- Surgery required (2nd trimester or postpartum)
• Nonstress test A noninvastive test (CTG) that measures fetal heart rate (FHR) reactivity to fetal movements. Indications:- Maternal medical conditions (e.g., oligohydramnios, gestational diabetes, preeclampsia)- Fetal conditions (e.g., fetal heart defects, fetal growth restriction) - Usually performed in the third trimester (after the 32nd gestational week)- A normal NST would show ≥ 2 FHR accelerations. Reactive nonstress: If the nonstress test was normal.- High-risk conditions: weekly nonstress tests- Uncomplicated pregnancy: reassure and discharge Non-reactive nonstress test: if the NST is nonreactive (< FHR accelerations)1. Perform vibroacoustic stimulation and record the NST for another 20 minutes2. If the NST is still non-reactive: check the biophysical profile (BPP) or perform contraction stress test
• Biophysical profile A noninvasive test that evaluates the risk of antenatal fetal death, performed using information from the nonstress test and ultrasound. Performed continuous observation for ≥ 30 minutes. Each parameter receives a score of either 0 (abnormal) or 2 (normal) points1. Nonstress test: Reactive fetal heart rate monitoring2. Amniotic fluid volume: Single fluid pocket ≥ 2 cm x 1 cm or amniotic fluid index > 53. Fetal movements: ≥ 3 general body movements4. Fetal tone: ≥ 1 episodes of flexion/extension of fetal limbs or spine5. Fetal breathing movements: ≥ 1 breathing episode for ≥ 30 seconds Interpretation:Total score ≥ 8 points: no signs of fetal compromise at the time of testing → reassuranceTotal score ≤ 4 points: potential fetal compromise → delivery is indicated If score equivocal and the baby is premature (gestational age < 36 weeks), a contraction stress test makes sense.
• Maternal serum AFP screening ↑ AFP:- Open neural tube defects (eg, anencephaly, open spina bifida)- Ventral wall defects (eg, omphalocele, gastroschisis)- Multiple gestation ↓ AFP:- Aneuploidies (eg, trisomy 18 & 21)
• Multiple gestations – Complications Maternal complications:- Hyperemesis gravidarum- Preeclampsia- Gestational diabetes mellitus- Iron-deficiency anemia Fetal complications:- Congenital anomalies- Fetal growth restriction- Preterm delivery- Malpresentation (eg, breech)- Monochorionic twins: Twin-twin transfusion syndrome- Monoamniotic twins: Conjoined twins, cord entanglement
• Baseline fetal heart rate Fetal tachycardia (> 160/min)- Maternal fever (eg, intraamniotic infection)- Medication side effect (eg, beta agonists)- Fetal hyperthyroidism- Fetal tachyarrhythmia Fetal bradycardia (< 110/min)- Maternal hypothermia- Medication side effect (eg, beta blockers)- Fetal hypothyroidism- Fetal heart block (eg, anti-Ro/SSA, anti-La/SSB)
• Common problems related to lactation Engorgement: Bilateral, symmetric fullness, tenderness & warmth- Treatment: Cold compresses, acetaminophen, NSAIDs, regular pumping Nipple injury: Abrasion, bruising, cracking &/or blistering from poor latch Plugged duct: Focal tenderness & firmness &/or erythema; no fever Galactocele: Subareolar, mobile, well-circumscribed, nontender mass; no fever Mastitis: Tenderness/erythema + fever Abscess: Symptoms of mastitis + fluctuant mass; axillary lymphadenopathy Mammary candidosis: Unilateral, stabbing breast pain out of proportion to examination; scaling of the skin on the nipple
• Exercise during pregnancy Absolute contraindications:- Amniotic fluid leak- Cervical incompetence- Multiple gestation- Placenta abruption or previa- Premature labor- Preeclampsia/gestational hypertension- Severe heart or lung disease Unsafe activities:- Contact sports (e.g., basketball, ice hockey, soccer)- High fall risk (e.g., downhill skiing, gymnastics, horseback riding)- Scuba diving- Hot yoga
• Fetal growth restriction Definition: Weight < 10th percentile for gestational age Risk factors:- Maternal hypertension- Pregestational diabetes mellitus- Genetic abnormalities- Congenital infection Appearance:- Large anterior fontanel- Thin umbilical cord- Loose, peeling skin- Minimal subcutaneous fat Evaluation:- Placenta histopathology- Consider karyotype, urine toxicology, serology Neonatal complications:- Polycythemia- Hypoglycemia- Hypocalcemia- Poor thermoregulation
• Pseudocyesis Rare psychiatric condition with somatic symptoms. Women present with classic signs of pregnancy despite it being ruled out with ultrasound and negative pregnancy test.
• Physiologic changes during pregnancy Skin: Melasma Cardiac:- ↑ Plasma volume (10-15%)- ↑ RBC mass (20-30%)- ↑ Cardiac output by ↑ preload, ↓ systemic vascular resistance (progesterone), ↑ heart rate- Hypercoagulability- ↑ Fibrogen (→ normal fibrogen at pregnancy is sign for DIC) and ↑ D-dimer (→ no use for evaluation of thrombosis) Pulmonary:- The diaphragm is displaced upwards → ↓ total lung capacity, residual volume, functional residual capacity- ↑ Minute ventilation (50%) by ↑ tidal volume (no change in respiratory rate) Genitourinary:- ↑ GFR (→ creatinine is lower) due to ↓ SVR and progesterone can dilate renal pelvices Weight gain:- BMI < 18.5 → 1 lb/week (28-40 lbs)- BMI 18.5-24.9 → 0.75 lb/week (25-35 lbs)- BMI 25-29.9 → 0.5 lbs/week (15-25 lbs)- BMI > 30 → 0.25 lbs/week (11-20 lbs) Gastrointestinal:- Constipation, GERD, nausea, 5 "Fs" Endocrine:- Estrogen: Hypercoagulability- Prolactin: Nipple discharge Musculoskeletal: - Increased lumbar lordosis; relaxation of the ligaments supporting the joints of the pelvic girdle in preparation for childbirth → can cause lower back pain
• Nutrition during pregnancy - Limit caffeine intake: daily recommended dose < 200 mg- Avoid alcohol and tobacco use throughout pregnancy- Avoid raw fish (contamination with parasites and bacteria) and seafood of unknown origin (methylmercury contamination)- Aoid raw milk products: high risk of congenital listeriosis- Avoid raw meat: high risk of congenital toxoplasmosis Supplementation:- Folic acid (0.4-0.8 mg/day): Ideally, women should begin intake 4 weeks prior to pregnancy and continue with this dose for at least the first 2-3 months of pregnancy.- Vitamin B12: Recommended for pregnant women who adhere to a vegan diet- Iron: 30-60 mg/day: most common type of anemia in pregnancy- Calcium: 1000-1300 mg/day (50% increase)- Iodine: 250 μg/day
• High-risk pregnancies - Family history (medical and obstetric) of complicated pregnancies- Advanced maternal age (> 35 years)- First pregnancy- Multiple pregnancy- Multiparity (> 5 births)- Medical conditions (antiphospholipid syndrome, arterial hypertension, diabetes mellitus, epilepsy, malignancies)- Social and environmental factors (e.g., drug use, stress)- Pre-existing gynecological conditions: uterine myoma, history of uterine surgery- Prior complicated pregnancies→ Premature delivery (< 38 weeks), baby with low birth weight, or a baby born with congenital defects→ Prior cesarean section→ Rhesus incompatibility→ History of > 2 abortions or placental abruption
• Uncomplicated nausea and vomiting (“morning sickness”) Epidemiology: occurs in up to 90% of pregnancies; onset at 5-6 weeks' gestation, peaking at 9 weeks' gestation, usually abating by 16-20 weeks' gestation Risk factors:- Nulliparity- Migraine- Multiple gestation- Hydatidiform mole- GERD Clinical features:- Nausea and/or vomiting- Normal vital signs, lab findings, and normal physical examination Treatment:- Rehydration- Nausea management: → Adapt diet and avoid triggers (small meals every 1-2 hours)→ First-line: ginger and/or pyridoxine (vitamin B6)→ Second-line: add doxylamine→ Third-line: administer antiemetics (e.g., dimenhydrinate or diphenhydramine)
• Maternal complications during pregnancy - Supine hypotensive syndrome: compression of the vena cava and pelvic veins by the uterus→ Tachycardia, dizziness, and nausea, and occasionally causes syncope.- Peripheral edema→ Management: Rule out DVT and preeclampsia- Lower back pain: increased lumbar lordosis caused by relaxation of the ligaments supporting the joints of the pelvic girdle in preparation for childbirth- Carpal tunnel syndrome - Hypertensive pregnancy disorders- Gestational diabetes- Pregnancy pyelonephritis (most common pregnancy complication)- Gastrointestinal reflux- Bleeding during pregnancy- Placenta praevia
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• Prenatal care Safety and risk:- Genetic Disease- Carrier States- Domestic Violence- Maternal Complications Folic acid: Neural tube defects Vaccinations:- Influenza- Hep B- MMR (live attenuated) Lifestyle:- Smoking cessation - Alcohol cessation - Exercise, sleep, stress management Optimize Pre-existing disease: Diabetes, hypertension, thyroid
• Urinary tract infection in pregnancy Pregnancy may increase the risk of recurrent bacteriuria and UTIs due to urinary stasis (caused by increased progesterone), ureteral smooth muscle relaxation and dilation, increased pressure on the bladder from the uterus, and immunosuppression. Asymptomatic bacteriuria: Screening for asymptomatic bacteriuria is recommended for all pregnant women in the first trimester.- Diagnostic criteria for asymptomatic bacteriuria on urine culture: two consecutive urine samples with the same pathogen with > 105 CFU/mL- Treatment is always required for asymptomatic bacteriuria in pregnancy because asymptomatic bacteriuria is more likely to lead to pyelonephritis in pregnant women than in nonpregnant women. Treatment options include:- Beta-lactam antibiotics (e.g., amoxicillin-clavulanate, cefpodoxime)- Fosfomycin- TMP-SMX, nitrofurantoin- Follow-up culture is required
• Contraction stress test A test to assess the response of the fetal heart rate to contractions indicated in high-risk pregnancies. Performed in non-reactive stress tests or equivocal BPP scores in premature infants (< 36 weeks gestation). Measures FHR reactivity in response to uterine contractions stimulated with oxytocin.- An adequate test requires 3 contractions every 10 minutes.- Testing is considered positive if > 50% of contractions are followed by late decelerations in FHR. - Positive testing may indicate adverse outcomes of the fetus. Early decelerations = head compressionVariable decelerations = cord compressionLate decelerations = uteroplacental insufficiency Contraindications (= contraindications to labor):- Placenta previa- Prior myomectomy
• Alloimmunization Rhesus D Lewis - don’t cause fetal anemia I - don’t cause fetal anemia Kell and Duffy antibodies can cause erythroblastosis fetalis Lewis Lives, Kell Kills, and Duffy Dies Rh Ab titer < 1:8 → STOPRh Ab titer ≥ 1:8 → Transcranial doppler↑ Flow in transcranial doppler (= anemia) → Gestational age- < 32 weeks → Percutaneous umbilical cord sampling (PUBS) + Transfuse- > 32 weeks → Deliver
• Obstetric laceration Tear of the perineal body due to significant or rapid stretching forces during labor and delivery; most common obstetric injury of the pelvic floor I°: Cutaneous to subcutaneous tissue tear (skin, fourchette, posterior vaginal wall) II°: Structures in first degree lacerations and the perineal muscles III°: Structures in second degree lacerations with involvement of the external anal sphincter → can cause fecal incontinence due to sphincter involvementIV°: Structures in third degree lacerations and the anterior wall of the anal canal or rectum (mucosa)
• Anesthesia The pain of Stage I comes from T10-T12 (visceral pain). The pain of Stage II comes from S2-S4 (somatic pain).
• Hepatitis B HBsAg ⊕ mother1. C-section to reduce the blood exposure. 2. Give baby IVIG Hep B as well as Hep B vaccine on the day of delivery.3. Breast feeding is OK HBsAG ⊝ Mom - Hepatitis B vaccine within 2 months Mom ?- Baby: Hepatitis B vaccine at birth- Check mom's HBsAg
• Maternal hypertensive crisis Severe hypertension = ≥ 160/≥ 110 mmHg for ≥ 15 minutes First-line drugs:- Hydralazine IV- Labetalol IV: Do not use in bradycardic patients (can cause dizziness or lightheadedness)- Nifedipine POIndication: Lower blood pressure acutely to decrease stroke risk Drug: Magnesium sulfate IV or IMIndication: Prevent or treat eclamptic seizures
• Pregnancy management in patients with HSV Prior HSV infection → Antiviral suppression beginning at 36 weeks Lesion/prodromal symptoms during labor → C-section
• Amniotic fluid embolism Risk factors:- Advanced maternal age- Gravida ≥ 5 (live births or stillbirths)- Cesarean or instrumental delivery- Placenta previa or abruption- Preeclampsia Clinical presentation:- Mostly occurs during labor- Respiratory collapse: hypoxia, dyspnea, tachypnea, cough, cyanosis, basal crepitations, acute respiratory distress syndrome- Cardiovascular collapse: hypotension, arrhythmias, cardiac arrest- Altered consciousness (drowsiness, seizures)- Features of disseminated intravascular coagulation (e.g., uterine hemorrhage, bleeding from all IV catheter sites, skin bruising)- Fetal bradycardia Treatment:- Correction of hypoxia: high flow oxygen or intubation and mechanical ventilation- Correction of hypotension/shock: vasopressors (noradrenaline or dopamine)- Correction of anemia and coagulopathy: transfusion of platelet/fresh frozen plasma (FFP) and packed red blood cells- Emergency cesarean section
• Indications for prophylactic administration of anti-D immune globulin Rh(D)-negative patients:- At 28-32 weeks gestation- < 72 hours after delivery of Rh(D)-positive infant- < 72 hours after spontaneous abortion- Ectopic pregnancy- Threatened abortion- Hydatidiform mole- Chorionic villus sampling, amniocentesis- Abdominal trauma- 2nd & 3rd-trimester bleeding- External cephalic version
• Short interpregnancy interval Definition: < 6-18 months from delivery to next pregnancy Complications:- Maternal anemia (maternal folate and iron stores are depleted)- PPROM (persistent genital tract inflammation)- Preterm delivery- Low birth weight Prevention: Appropriate pregnancy timing with interval contraception (eg, progestin-containing intrauterine device) is recommended for adequate maternal recovery and optimization for future pregnancies.
• Induction of labor Indications:- Post-term pregnancy (≥ 42 weeks of pregnancy or gestation)- Preterm premature rupture of membranes after 34 weeks- Premature rupture of membranes at term- Hypertension during pregnancy, preeclampsia, eclampsia, HELLP syndrome- Maternal diabetes to avoid post-term pregnancy (risk of macrosomia)- Intrauterine death Contraindications:- History of uterine rupture; previous high risk cesarean section- Placenta previa- Vasa previa- Transverse fetal lie- Cord prolapse- Active maternal genital herpes- Nonreassuring fetal heart rate Modified Bishop score: Used to assess the cervix and the likelihood of a successful induction- Bishop score ≥ 8 → favorable cervix for vaginal delivery- Bishop score ≤ 6 → unripe or unfavorable cervix; not ready for vaginal delivery Approach:1. Membrane sweeping (shortens time to onset of labor): The clinician's finger is inserted beyond the internal cervical os, then brushed along the lower uterine segment in an attempt to separate the fetal membranes from the decidua (uterine lining).2. If the cervix is still unfavorable: cervical ripening with prostaglandin E1 or E2 (e.g., misoprostol)3. Maternal oxytocin infusion4. Consider amniotomy (only if the cervix is partially dilated and completely effaced, and the fetal head is well applied)
• Umbilical cord prolapse Acute, life-threatening emergency for the fetus, in which a part of the umbilical cord lies between the antecedent part of the fetus (mostly head) and the pelvic wall, causing rupture of membranes Epidemiology: rare (0.5% births) Etiology: often seen in presentation anomalies (e.g., breech presentation, transverse fetal position), multiple pregnancy, long umbilical cord, or abnormal fetal movement (polyhydramnios, premature birth) Clinical features: an abrupt change from a previously normal CTG to one with fetal bradycardia or recurrent, severe decelerations, occuring after the rupture of membranes Diagnostics: vaginal palpation → thick, pulsating cord is palpable Treatment: - Trendelenburg position- Fetus is pushed back into the uterus- Immediate tocolysis using β2-mimetics (e.g., fenoterol) → Emergency cesarean section
• Prematurity – Complications - Neonatal respiratory distress syndrome (RDS)- Bronchopulmonary dysplasia (BPD)- Patent ductus arteriosus (PDA)- Retinopathy of prematurity (ROP)- Necrotizing enterocolitis (NEC)- Periventricular leukomalacia (PVL)- Neurological disorders (e.g., cerebral palsy, learning disabilities, developmental delays, ADHD)- Problems of homeostasis: apnea, bradycardia, hypothermia- Infection and sepsis (e.g., pneumonia)- Anemia of prematurity: impaired ability to produce adequate erythropoietin (EPO); should be suspected in premature infants with low hemoglobin- Intraventricular hemorrhage (IVH)
• Neonatal soft tissue injuries Soft tissue injuries of the scalp in infants are mostly caused by shearing forces during vacuum or forceps delivery. Caput succedaneum: benign edema of the scalp tissue that extends across the suture lines Cephalohematoma: subperiosteal hematoma that is limited to cranial suture lines Subgaleal hemorrhage: bleeding between the periosteum of the skull and the aponeurosis that may extend across the suture lines; associated with a high risk of significant hemorrhage and hemorrhagic shock Whereas caput succedaneum and cephalohematoma are benign conditions and resolve spontaneously, subgaleal hemorrhages require close monitoring and fluid replacement to prevent hemorrhagic shock.
• Fetal hydantoin syndrome A collection of defects associated with maternal use of anticonvulsants, such as phenytoin. Due to impaired absorption of folate Features:- Intrauterine growth restriction- Craniofacial abnormalities (e.g., cleft palate, hypertelorism, slanted palpebral fissures, and low-set ears)- Short neck- Phalanx/fingernail hypoplasia
• HIV in pregnancy Transmission:- Highest risk during birth (perinatal vertical transmission)- Risk depends on maternal viral load Reducing risk of transmission:- Combined antiretroviral therapy (cART) is recommended throughout pregnancy  Delivery method - Viral load > 1,000 copies/mL near time of delivery: high risk of HIV transmission → Cesarean delivery should be scheduled at 38 weeks (even if the mother received cART during pregnancy)→ HIV post-exposure prophylaxis with zidovudine, lamivudine and nevirapine OR zidovudine and nevirapine- Viral load ≤ 1,000 copies/mL and mother has received cART during pregnancy: low risk of HIV transmission→ Vaginal delivery may be considered as an alternative to cesarean section→ HIV post-exposure prophylaxis with zidovudine for the newborn Breastfeeding should generally be avoided, because risk of transmission is 5-20%  Diagnosis in infants: if < 18 months, diagnosis is confirmed via PCR, not ELISA
• Diabetic fetopathy Onset: second and third trimester Pathophysiology: chronic fetal hyperglycemia → fetal hyperinsulinemia + islet cell hyperplasia, insulin-like growth factor, and growth hormones → ↑ metabolic effects and oxygen demand → fetal hypoxemia Effects:- Macrosomia → increased risk of birth injuries (e.g., shoulder dystocia)- Polycythemia - Neonatal hypoglycemia and other electrolyte imbalances (hypocalcemia, hypomagnesemia)- Respiratory distress (due to insufficient production of pulmonary surfactant)- Hypertrophic cardiomyopathy (polycythemia → redistribution of iron → iron deficiency in cardiac tissue AND hypoxemia → impaired cardiac remodeling)- Polyhydramnios (fetal hyperglycemia → fetal polyuria)
• Pregnancy loss Threatened abortion:- Vaginal bleeding- Fetal activity- Cervical os: closed- Reversible Inevitable abortion:- Vaginal bleeding, and visible/palpable products of conception- Fetal activity may be present.- Cervical os: dilated- Irreversible Missed abortion:- No bleeding- No expulsion of the products of conception- No fetal activity- Cervical os: closed- Irreversible Incomplete abortion:- Vaginal bleeding; products of conception within the cervical canal or uterus- Usually occurs > 12 weeks' gestation- Cervical os: dilated- Irreversible Complete abortion:- Vaginal bleeding; products of conception completely outside of the uterus- Usually occurs < 12 weeks' gestation- Cervical os: closed- Irreversible Stillbirth:- Absence of fetal movements and cardiac activity- Cervical os: variable- Irreversible Treatment: Inevitable, incomplete, or missed abortions- Expectant management (option for women < 14 weeks gestation): Surgical evacuation is usually recommended if evacuation does not occur after 4 weeks.- Medical evacuation: Misoprostol is used to induce cervical ripening and expulsion of the products of conception.- Surgical evacuation (dilation and curettage): preferred method in septic abortion or if there is heavy bleeding or significant maternal disease

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