Eduovisual
Pregnancy, Childbirth & Puerperium
Macrosomia: management and delivery planning
— Large for gestational age (LGA) is a related but distinct term: birth weight > 90th percentile for gestational age. A 3800 g baby at 36 weeks is LGA but not macrosomic.
— Fundal height > gestational age + 3 cm on serial measurements
— Maternal diabetes (pregestational T1/T2DM or GDM, especially A2GDM)
— Excessive gestational weight gain or pre-pregnancy obesity (BMI ≥ 30)
— Prior macrosomic infant (recurrence risk ~15–30%)
— Post-term pregnancy (≥ 41 weeks)
— Maternal age > 35, multiparity, male fetus, certain ethnicities, hereditary overgrowth syndromes (Beckwith-Wiedemann)
Board pearl: EFW by third-trimester ultrasound has a ± 15% error — a sonographic "4200 g" baby can actually be 3570–4830 g. Never base a cesarean recommendation on a single ultrasound number alone; combine EFW with maternal diabetes status, prior obstetric history, and pelvimetry/clinical judgment.
Step 3 management: A patient with fundal height lagging or leading by > 3 cm warrants ultrasound — this is the single most testable trigger for growth assessment in the ambulatory prenatal setting.
— Third-trimester patient with poorly controlled GDM (fasting > 95, 1-h postprandial > 140) presenting at 32–36 weeks for routine visit; fundal height exceeds dates.
— Obese multipara with prior 4200 g infant complicated by shoulder dystocia, now at 36 weeks requesting delivery planning.
— Post-term patient (41+ weeks) without prior prenatal care, large abdomen on palpation.
— Patient with Beckwith-Wiedemann features on anatomy scan (omphalocele, macroglossia, organomegaly) plus accelerated growth.
— Glycemic history: Pregestational vs gestational diabetes; HbA1c trajectory; insulin vs metformin vs diet-controlled; recent fingerstick logs (target fasting < 95, 1-h pp < 140, 2-h pp < 120).
— Obstetric history: Prior macrosomia, prior shoulder dystocia, prior operative vaginal delivery, prior 3rd/4th degree laceration, prior cesarean indication.
— Pregnancy course: Accuracy of dating (first-trimester crown-rump length is gold standard), weight gain trajectory vs IOM targets, polyhydramnios on prior scans.
— Maternal medical: BMI, hypertension, thyroid status, family history of large infants or overgrowth syndromes.
— Social: Tobacco (paradoxically lowers birth weight — its absence is a permissive factor), prenatal vitamin/folate adherence.
— Abdominal distension, early satiety, severe heartburn, dyspnea (uterine size), worsening lower-extremity edema, reduced fetal movement perception in a crowded uterus.
Key distinction: A patient with pregestational diabetes is at risk for asymmetric macrosomia — disproportionately enlarged shoulders/trunk relative to head — which dramatically raises shoulder dystocia risk independent of total weight. A constitutionally large baby from tall, non-diabetic parents tends to grow symmetrically and carries lower dystocia risk per gram.
Board pearl: Always recompute the EDD from earliest reliable ultrasound; "macrosomia" diagnosed against a wrong gestational age is the classic exam trap.
— Fundal height measured from symphysis pubis to top of fundus in cm; should approximate gestational age in weeks (± 2 cm) from 20–36 weeks. > 3 cm discrepancy above dates triggers ultrasound.
— Caveats reducing fundal height accuracy: maternal obesity, fibroids, polyhydramnios, multiple gestation, transverse lie, full bladder. In BMI ≥ 35, fundal height is unreliable — go straight to serial growth ultrasounds every 4 weeks.
— Estimate fetal weight by palpation (clinically as accurate as ultrasound in experienced hands, ~ ± 15%).
— Identify presentation (breech LGA fetus is a strong cesarean indication), lie, and engagement. Floating head at term in a suspected macrosomic fetus raises concern for cephalopelvic disproportion.
— Clinical pelvimetry has limited predictive value but a flat, android, or platypelloid pelvis with a prominent ischial spine narrows the safe corridor for vaginal delivery of a large fetus.
— Nonstress test (NST) and biophysical profile (BPP) starting at 32 weeks if pregestational diabetes, 36 weeks if A2GDM, and as clinically indicated for IUGR-risk comorbidities.
— Amniotic fluid index (AFI) > 24 or single deepest pocket > 8 cm = polyhydramnios, commonly co-travels with macrosomia in diabetic pregnancies and independently raises risk of cord prolapse and abruption.
Step 3 management: In a 34-week obese diabetic with fundal height 38 cm, the next step is growth ultrasound with AFI and umbilical artery Doppler — not immediate delivery, not immediate cesarean scheduling. Diagnose precisely before planning route.
Board pearl: Document Leopold-estimated fetal weight and ultrasound EFW side-by-side at 36–37 weeks — concordance strengthens any delivery-route recommendation.
— Biometry parameters: biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), femur length (FL). AC is the single most sensitive marker for macrosomia — AC > 35 cm at term or AC > 90th percentile predicts macrosomia better than composite EFW.
— EFW formulas (Hadlock most common) carry ± 10–15% error; accuracy worsens at the extremes (true macrosomic fetuses are systematically underestimated).
— HC/AC ratio < 10th percentile suggests asymmetric (diabetic-pattern) macrosomia → higher shoulder dystocia risk.
— Repeat scan no more frequently than every 3–4 weeks to track velocity (single scans can mislead).
— If GDM screen not yet done or borderline: 1-h 50 g glucose challenge → 3-h 100 g OGTT if abnormal. Carpenter-Coustan thresholds: fasting 95, 1-h 180, 2-h 155, 3-h 140. Two abnormal = GDM.
— In late-pregnancy new macrosomia with prior normal screen, consider HbA1c and a repeat OGTT — undiagnosed type 2 diabetes does present this way.
Key distinction: EFW > 4500 g in diabetic pregnancy and EFW > 5000 g in non-diabetic pregnancy are ACOG-endorsed thresholds at which scheduled cesarean delivery is a reasonable offering — these are offers, not mandates, and require shared decision-making.
Board pearl: MRI pelvimetry is not routinely recommended for suspected macrosomia — low yield, high cost, no outcome improvement. Ultrasound + clinical judgment is the standard.
— Repeat growth ultrasound at 38–39 weeks when delivery decision is approaching, since interval growth in the final weeks can shift EFW past the 4500 g decision threshold.
— 3D ultrasound for soft-tissue measurements (cheek-to-cheek diameter, mid-thigh subcutaneous tissue) — research tools, not routine.
— MRI is considered only when ultrasound is technically inadequate (severe maternal obesity, anhydramnios) or to evaluate suspected fetal anomaly (omphalocele in Beckwith-Wiedemann).
— Beckwith-Wiedemann syndrome: macroglossia, omphalocele, hemihyperplasia, hyperinsulinemic hypoglycemia. Refer for fetal echo, genetics consult, plan delivery at tertiary center with NICU and pediatric surgery.
— Sotos, Perlman, Simpson-Golabi-Behmel — rare, suspect with polyhydramnios + structural anomalies + extreme overgrowth.
— Type and screen at 36 weeks (high postpartum hemorrhage risk).
— Confirm Rh status and anti-D prophylaxis given at 28 weeks if Rh-negative.
— Recheck HbA1c in known diabetics within 4 weeks of anticipated delivery — supports neonatology preparation.
— Obese parturients with macrosomic fetuses should have a prenatal anesthesia consult at 34–36 weeks — anticipates difficult neuraxial placement, difficult airway, and the elevated probability of urgent cesarean.
Step 3 management: Suspected Beckwith-Wiedemann on prenatal imaging → coordinate delivery at a tertiary center, plan neonatal glucose monitoring (q1h × first hours), and arrange genetics + pediatric surgery consultation before delivery, not after.
Board pearl: A persistent single umbilical artery plus macrosomia raises concern for occult structural anomaly — escalate to detailed anatomy reassessment and fetal echo.
— EFW < 4000 g: Routine management; no special intervention based on size alone.
— EFW 4000–4499 g, no diabetes, no prior shoulder dystocia: Expectant management, allow spontaneous labor. Induction for suspected macrosomia in non-diabetics does NOT reduce cesarean or shoulder dystocia rates (and may not improve outcomes — though the Boulvain trial suggested induction at 37–38 weeks reduces shoulder dystocia in this group; ACOG considers it reasonable but not mandatory).
— EFW ≥ 4500 g WITH diabetes: Offer scheduled cesarean — strongest indication. Shoulder dystocia risk approaches 20–50%.
— EFW ≥ 5000 g WITHOUT diabetes: Offer scheduled cesarean.
— Prior shoulder dystocia with neonatal injury: Strongly consider cesarean regardless of current EFW.
— Pregestational diabetes, well-controlled: 39 0/7 – 39 6/7 weeks
— Pregestational diabetes, poorly controlled or vasculopathy: 36 0/7 – 38 6/7, individualized
— GDM A1 (diet-controlled): 39 0/7 – 40 6/7 weeks
— GDM A2 (medication-controlled), well-controlled: 39 0/7 – 39 6/7
— GDM A2, poorly controlled: 37 0/7 – 38 6/7
— Suspected macrosomia without diabetes: No indication to deliver before 39 weeks solely for size.
Key distinction: The number needed to treat (NNT) with cesarean to prevent one permanent brachial plexus injury is ~155–588 in non-diabetics with EFW ≥ 4500 g — high enough that universal cesarean is not justified; low enough that offering it is. In diabetics, NNT drops sharply, justifying the lower 4500 g threshold.
Board pearl: "Suspected macrosomia" alone is not an indication for cesarean below the ACOG thresholds. Tested repeatedly.
— Targets: fasting < 95, 1-h postprandial < 140, 2-h postprandial < 120. HbA1c < 6.0–6.5% if achievable without hypoglycemia.
— Diet (A1GDM): medical nutrition therapy with carbohydrate distribution across 3 meals + 2–3 snacks; ~40% carb, 20% protein, 40% fat.
— Insulin is first-line pharmacotherapy for GDM requiring medication (ACOG). NPH + short-acting (regular or aspart/lispro) split-dose regimen. Insulin does not cross the placenta.
— Metformin and glyburide are alternatives but cross the placenta; ACOG considers them second-line. Glyburide associated with higher macrosomia and neonatal hypoglycemia rates than insulin.
— Normal BMI: 25–35 lb total
— Overweight: 15–25 lb
— Obese: 11–20 lb
— Excess gain accelerates fetal growth even in non-diabetics.
— NST + AFI twice weekly from 32 weeks in pregestational diabetes; from 36 weeks in A2GDM; case-by-case in A1GDM.
— Growth ultrasound every 4 weeks from 28–32 weeks onward in diabetic pregnancies.
— Daily kick counts from 28 weeks
— Pre-eclampsia warning signs (headache, RUQ pain, scotomata)
— Recognition of labor in a large uterus (may have less clear contraction perception)
Step 3 management: A GDM patient with fasting glucose persistently 105 despite dietary adherence — start insulin, do not increase oral agent or "wait one more week." Persistent hyperglycemia from 28 weeks onward is the driver of macrosomia; every week of delay matters.
Board pearl: Insulin is first-line for GDM medication therapy on Step 3 — even though metformin/glyburide appear in real-world practice.
— Continuous electronic fetal monitoring
— Adequate IV access (18-gauge or larger), type and screen active
— Anesthesia in-house awareness; epidural placed early in obese parturients
— Avoid prolonged second stage — consider operative vaginal delivery cautiously; vacuum + forceps + macrosomia is the highest-risk combination for shoulder dystocia. Many experts avoid operative vaginal delivery if EFW > 4500 g.
— Head delivers then retracts ("turtle sign"); chin tight against perineum; failure of restitution; gentle downward traction fails to deliver anterior shoulder.
— Help (call for OB, anesthesia, NICU, extra nurses; note time)
— Evaluate for episiotomy (consider if needed for room for internal maneuvers — not therapeutic itself)
— Legs — McRoberts maneuver (hyperflex maternal hips to abdomen) — first-line, resolves ~40%
— Pressure — suprapubic pressure (not fundal — fundal worsens impaction)
— Enter — internal maneuvers (Rubin II, Woods corkscrew)
— Remove posterior arm
— Roll patient to all fours (Gaskin maneuver)
— Neonatal exam for brachial plexus injury, clavicle/humerus fracture
— Maternal exam for 3rd/4th degree laceration, PPH
— Detailed documentation: time of head delivery, time of body delivery, maneuvers used, order, who performed, neonatal cord gases, Apgars
CCS pearl: When you suspect shoulder dystocia in a CCS case: order "call for help," McRoberts maneuver, suprapubic pressure" as the immediate first three actions — and never order fundal pressure, which is a wrong-answer trap.
Board pearl: Document everything — shoulder dystocia is among the most litigated obstetric events.
— Elevated baseline rates of GDM, hypertension, and macrosomia
— Lower threshold for induction at 39–40 weeks given rising stillbirth risk
— Counsel earlier about delivery planning and anesthesia consult
— Diabetic nephropathy raises risk for both IUGR (vascular insufficiency) and macrosomia (hyperglycemia) — paradox depends on glycemic vs vascular dominance
— Tighter BP control (target < 135/85), nephrology co-management
— Avoid ACEi/ARB (teratogenic); labetalol, nifedipine, methyldopa preferred
— Intrahepatic cholestasis of pregnancy (ICP) is not directly linked to macrosomia but co-occurs with GDM; both push toward earlier delivery (36–37 wks for severe ICP)
— Bile acids > 100 µmol/L = deliver at 36 weeks regardless of fetal size
— Strongest non-glycemic risk factor for macrosomia
— Pre-pregnancy weight loss/bariatric surgery counseling between pregnancies
— Anesthesia consult by 34 weeks
— Wound complications post-cesarean: subcutaneous closure if ≥ 2 cm depth; negative-pressure wound therapy considered
— Increased VTE risk — sequential compression devices on admission; pharmacologic prophylaxis if additional risk factors
— Macrosomia rarely the driver; mode-of-delivery is driven by cardiac lesion. Avoid Valsalva in lesions intolerant of preload swings — assisted second stage with forceps or vacuum may be safer than prolonged pushing despite EFW concerns.
Step 3 management: A BMI 45 patient at 36 weeks with EFW 4200 g and GDM A2 — schedule anesthesia consult, growth ultrasound at 38 weeks, delivery plan at 39 weeks with cesarean offered if EFW ≥ 4500 g. Don't deliver early just for size in a controlled diabetic.
Board pearl: Obesity-driven macrosomia responds best to interpregnancy weight optimization, not late-pregnancy intervention.
— Highest absolute risk of macrosomia and shoulder dystocia among any group
— Preconception HbA1c < 6.5% halves congenital anomaly and macrosomia rates
— Insulin pump or multiple daily injections; CGM use improves outcomes
— Delivery timing: 39 0/7 if well-controlled, no vasculopathy; earlier (36–38 weeks) if poor control, hypertension, or prior stillbirth
— Postpartum insulin requirements drop ~50% immediately after placental delivery — anticipate hypoglycemia, halve basal rate
— Often presents with worse pre-pregnancy control than T1DM; transition off non-insulin agents (except metformin in some protocols) before or early in pregnancy
— Same delivery timing principles as T1DM
— Prior macrosomic infant → 15–30% recurrence; counsel about interpregnancy weight loss, glycemic screening with HbA1c preconception, early GDM screen (first trimester) in subsequent pregnancy
— Prior shoulder dystocia with permanent injury → strong indication for elective cesarean in next pregnancy
— Prior shoulder dystocia without injury → individualized; many opt for cesarean if EFW approaches prior delivery weight
— Macrosomia less common (smaller maternal frame, lower diabetes prevalence) but cephalopelvic disproportion more common when it occurs
— Macrosomia per fetus is rare; total uterine volume drives delivery timing decisions
Key distinction: Pregestational diabetes confers risk throughout organogenesis (anomalies + macrosomia); gestational diabetes confers risk mostly in late pregnancy (macrosomia, neonatal hypoglycemia, not congenital anomalies because it develops after organogenesis).
Board pearl: A diabetic woman planning pregnancy should achieve HbA1c < 6.5% before conception — this is the single highest-yield prevention strategy for macrosomia and its complications.
— Postpartum hemorrhage (uterine atony from overdistension) — leading immediate maternal complication; have oxytocin, methylergonovine, carboprost, misoprostol, tranexamic acid ready
— 3rd/4th degree perineal lacerations — risk doubles with EFW > 4000 g
— Operative vaginal delivery failure → emergency cesarean
— Uterine rupture in TOLAC with macrosomic fetus (cesarean more strongly preferred)
— Prolonged labor, arrest of descent, cephalopelvic disproportion
— Shoulder dystocia (1.4% overall; ~10% at 4000–4499 g; ~20–50% at ≥ 4500 g in diabetics)
— Brachial plexus injury — Erb-Duchenne palsy (C5–C6, "waiter's tip"), Klumpke palsy (C8–T1, "claw hand"); ~10% of plexus injuries are permanent
— Clavicular fracture — usually heals well, palpable callus by 2 weeks
— Humeral fracture — less common, requires immobilization
— Hypoxic-ischemic encephalopathy from prolonged dystocia
— Neonatal hypoglycemia — fetal hyperinsulinemia from maternal hyperglycemia; check glucose at 30 min, 1, 2, 4, 6 h; treat < 40 mg/dL
— Polycythemia, hyperbilirubinemia, hypocalcemia, respiratory distress, transient hypertrophic cardiomyopathy in infants of diabetic mothers
— Childhood obesity, metabolic syndrome, type 2 diabetes risk elevated in macrosomic infants — counsel breastfeeding, healthy infant feeding
— Maternal: 50% lifetime risk of T2DM after GDM
Step 3 management: Every infant of a diabetic mother and every macrosomic infant gets scheduled glucose checks starting within 30 min of birth and feeding initiated within 1 hour. Asymptomatic hypoglycemia < 40 → enteral feed; < 25 or symptomatic → IV dextrose D10 2 mL/kg bolus.
Board pearl: Klumpke palsy is rare and almost always seen with breech extraction, not cephalic shoulder dystocia (which causes Erb palsy).
— EFW > 5000 g
— Suspected overgrowth syndrome (Beckwith-Wiedemann) — needs Level III/IV NICU, pediatric surgery
— Pregestational diabetes with vasculopathy, prior poor outcome
— BMI > 50 without local anesthesia/critical care capability
— Prior shoulder dystocia with severe neonatal injury
— Shoulder dystocia → activate OB rapid response immediately; mobilize anesthesia, NICU, and second OB
— Failed McRoberts + suprapubic pressure within 60 seconds → proceed to internal maneuvers (do not repeat external maneuvers)
— Massive postpartum hemorrhage → activate massive transfusion protocol (1:1:1 RBC:FFP:platelets), consider B-Lynch suture, uterine artery embolization, peripartum hysterectomy
— Hemorrhagic shock unresponsive to initial resuscitation
— Eclampsia, HELLP with end-organ dysfunction
— Pulmonary edema from aggressive resuscitation or peripartum cardiomyopathy
— Amniotic fluid embolism (rare, but macrosomia + difficult delivery raises risk)
— Hypoglycemia refractory to enteral feeds → NICU for IV dextrose, glucagon if severe
— Suspected brachial plexus injury → pediatric neurology and orthopedic referral within first week; most resolve by 3 months but persistent deficits at 1 month → MRI and surgical evaluation
— HIE → therapeutic hypothermia within 6 hours of birth (cooling protocol)
CCS pearl: In a CCS scenario with intrapartum hemorrhage, the order set is two large-bore IVs, crystalloid bolus, type and crossmatch 4 units, oxytocin 40 U in 1 L NS, methylergonovine 0.2 mg IM (avoid in hypertension), and call anesthesia + activate massive transfusion if continued bleeding. Don't forget tranexamic acid 1 g IV within 3 hours.
Board pearl: Time-stamped documentation of every maneuver and every minute of dystocia is medicolegally critical.
— True macrosomia (LGA fetus, large baby)
— Wrong dates / unreliable LMP — confirm with first-trimester CRL; the most common cause of apparent size–dates discrepancy
— Polyhydramnios — AFI > 24 cm or SDP > 8 cm; causes include maternal diabetes, fetal anomalies (TE fistula, duodenal atresia, anencephaly), TTTS, fetal infection (CMV, parvovirus, syphilis)
— Multiple gestation — twins, triplets; should be detected at first-trimester ultrasound
— Uterine fibroids enlarging during pregnancy under estrogen influence
— Molar pregnancy with coexistent fetus (very rare) — markedly elevated β-hCG, theca lutein cysts
— Maternal obesity falsely elevating fundal height measurement
— Ultrasound differentiates polyhydramnios (excess fluid, normal-sized fetus) from macrosomia (excess fetal weight)
— Doppler velocimetry to distinguish vascular insufficiency patterns
— Maternal serum α-fetoprotein elevation may signal open neural tube defect with polyhydramnios
— Confirm dates against earliest reliable ultrasound
— Ultrasound for fetal number, EFW, AFI, anatomy review
— Glucose screen (or rescreen) regardless of prior result
— TORCH if polyhydramnios without obvious explanation
Key distinction: Polyhydramnios with macrosomia strongly suggests uncontrolled maternal diabetes. Polyhydramnios with normal-sized or small fetus points to fetal swallowing impairment (CNS, GI anomaly) — opposite implications, opposite workups.
Board pearl: Always rule out polyhydramnios before attributing fundal height excess to macrosomia — they often coexist but require different counseling.
— Maternal ascites from preeclampsia, mirror syndrome (Ballantyne syndrome), or undiagnosed liver disease
— Massive uterine fibroids independent of fetal size
— Maternal ovarian mass (cyst, theca lutein cyst, neoplasm)
— Maternal severe constipation, urinary retention with distended bladder (fix before measuring fundal height)
— Bandl's ring (pathologic retraction ring) — uterine cause of arrested labor
— Conjoined twin or fetal anomaly preventing descent (e.g., large sacrococcygeal teratoma) — usually known antenatally
— Maternal pelvic mass obstructing outlet
— Edematous newborn from hydrops fetalis — appears large but is fluid-overloaded (Rh isoimmunization, parvovirus, α-thalassemia major)
— Overgrowth syndromes (Beckwith-Wiedemann, Sotos, Perlman) — disproportionate features
— Infant of diabetic mother with characteristic facies, organomegaly, cardiomegaly
— Persistent large uterus postpartum + bleeding → retained products, uterine atony, accreta spectrum
— Persistent macrosomia in subsequent pregnancies without GDM → consider undiagnosed maternal T2DM, occult overgrowth syndrome carrier status, paternal factors
Step 3 management: A 36-week patient with fundal height 42 cm, EFW 3400 g (normal), and AFI 28 cm has polyhydramnios, not macrosomia — workup should pivot to glucose screen, anatomy scan for fetal swallowing defects, and TORCH titers if anomaly identified.
Board pearl: A "large baby that turned out not to be macrosomic" is often hydrops — the differential matters because hydropic infants need resuscitation planning entirely different from macrosomic ones.
— Active management of third stage: oxytocin 10 U IM or 20–40 U in 1 L IV after delivery, controlled cord traction, uterine massage
— Monitor for delayed PPH up to 12 weeks
— Perineal/cesarean wound assessment; obese patients at high SSI risk
— VTE prophylaxis: ambulation, SCDs; pharmacologic prophylaxis for cesarean + additional risk factors (BMI ≥ 40, prolonged immobility, prior VTE)
— GDM patients require 75-g 2-hour OGTT at 4–12 weeks postpartum to detect persistent diabetes or prediabetes (ADA standard)
— If normal: screen every 1–3 years for life (T2DM lifetime risk ~ 50%)
— Pregestational diabetics: resume pre-pregnancy regimen at adjusted doses; halve basal insulin immediately post-delivery
— Breastfeeding — reduces maternal T2DM and childhood obesity risk; encourage exclusive breastfeeding for 6 months
— Weight loss before next pregnancy: every 1 BMI point lost reduces recurrence of GDM and macrosomia
— Contraception planning: progestin-only methods or LARC for diabetics with vascular disease; combined OCP acceptable if no contraindications
— Newborn screening, hearing screen, hip exam (shoulder dystocia infants — check for clavicular crepitus, asymmetric Moro)
— Brachial plexus injury: pediatric neurology by 1 month if no improvement
— Pediatrician aware of macrosomia/IDM status for ongoing growth and metabolic monitoring
Step 3 management: Schedule the postpartum 2-hour 75 g OGTT at 6 weeks for every GDM patient before they leave the hospital. This is the single most-missed and most-tested follow-up step in Step 3 GDM/macrosomia cases.
Board pearl: Document the postpartum OGTT in the discharge summary — care transitions to primary care fail here disproportionately.
— Initial contact within first 3 weeks for high-risk patients (diabetes, hypertension, obesity, prior macrosomia complication)
— Comprehensive visit by 12 weeks postpartum
— Address mood (postpartum depression screening with EPDS/PHQ-9), breastfeeding, contraception, glycemic status, weight, future pregnancy planning
— Endocrinology or primary care follow-up at 6–12 weeks
— HbA1c at 6–12 weeks, then every 3–6 months
— Annual retinal exam, urine albumin-creatinine ratio, lipid panel, foot exam
— Preconception counseling 3–6 months before next attempt at pregnancy with HbA1c < 6.5% goal
— Return to pre-pregnancy weight or lower by 12 months
— Physical activity ≥ 150 min/week moderate intensity
— Dietary referral if indicated; Mediterranean or DASH-pattern diets reasonable
— Pediatric well-child visits at 3–5 days, 2 weeks, 2 months
— Document birth injury status (Erb palsy, clavicle fracture) and ensure subspecialty referrals scheduled
— Track growth percentiles; macrosomic infants often cross down through percentiles in first months — that's expected
— Future pregnancy plan should include early (first-trimester) GDM screening with HbA1c
— Recurrence risk for macrosomia 15–30% — modifiable with interpregnancy weight loss and glycemic control
— Family planning: minimum 18-month interpregnancy interval optimizes outcomes
Step 3 management: A GDM patient seen at 6 weeks postpartum with normal OGTT — next step is lifestyle counseling + repeat screening in 1–3 years, not "no further screening needed." The latter answer is a high-yield Step 3 trap.
Board pearl: The "fourth trimester" is testable terminology — early contact within 3 weeks for high-risk patients is the current ACOG standard.
— Cesarean for suspected macrosomia is an offer, not a recommendation — document shared decision-making explicitly: EFW range and its ± 15% uncertainty, NNT to prevent brachial plexus injury, maternal cesarean morbidity (hemorrhage, infection, future placenta accreta risk), patient values
— A patient may decline offered cesarean for EFW ≥ 4500 g in diabetes; her autonomous refusal should be honored after thorough counseling — document understanding
— Patient cannot demand a cesarean for EFW below threshold as a "right," but maternal-request cesarean is reasonable to discuss after counseling on risks
— Among the most litigated obstetric events; contemporaneous documentation of time intervals, maneuvers, personnel, and neonatal exam is essential
— Use a standardized shoulder dystocia documentation template; many institutions mandate one
— Simulation-based team training reduces both event severity and litigation exposure — a quality/safety intervention worth recognizing on exam
— Failure to schedule and complete postpartum OGTT in GDM patients — a documented care-gap with measurable consequences; institutional protocols (auto-scheduling before discharge) close it
— Handoff to pediatrician: communicate macrosomia, birth injury, glucose monitoring results, IDM status
— Handoff to primary care for maternal long-term diabetes screening
— Suspected substance use during pregnancy contributing to outcomes — varies by state; know your reporting obligations
— Neonatal birth injury with permanent deficit may trigger institutional event review (root cause analysis), not necessarily reporting to state, but transparent disclosure to family is required
— Even when shoulder dystocia is managed perfectly, brachial plexus injury can occur — open, empathetic disclosure with apology where appropriate ("communication and resolution programs") reduces litigation and improves patient trust
Board pearl: Document the time of head delivery, time of body delivery, sequence and timing of each maneuver, personnel present, and neonatal cord gas/Apgar — this six-element documentation set is the medicolegal standard.
— Macrosomia threshold: 4000 g (counseling) / 4500 g (cesarean consideration in diabetes) / 5000 g (cesarean consideration in non-diabetes)
— Shoulder dystocia incidence: 0.6–1.4% overall; 10% at 4000–4499 g; 20–50% at ≥ 4500 g with diabetes
— Brachial plexus injury after shoulder dystocia: ~10%; permanent: ~10% of those (so ~ 1% of shoulder dystocias)
— Ultrasound EFW error: ± 15%
— GDM lifetime T2DM risk: ~ 50%
— Macrosomia recurrence: 15–30%
— IDM facies: round cheeks, plethora, organomegaly, hypoglycemia, hypocalcemia, polycythemia, transient hypertrophic cardiomyopathy, respiratory distress
— Beckwith-Wiedemann: macrosomia + macroglossia + omphalocele + hemihyperplasia + hyperinsulinemic hypoglycemia + Wilms tumor risk
— Erb palsy ("waiter's tip"): C5–C6, anterior shoulder injury, most common
— Klumpke palsy ("claw hand" + Horner): C8–T1, posterior arm/breech extraction
— Insulin: first-line for GDM medication therapy
— Glyburide and metformin: cross placenta, second-line
— ACEi/ARB, statins, warfarin, methotrexate: contraindicated
— Methylergonovine: avoid in hypertension/preeclampsia
— Carboprost: avoid in asthma
— First maneuver for shoulder dystocia: McRoberts
— Never use fundal pressure in shoulder dystocia — worsens impaction
— Suprapubic, not fundal, pressure
Board pearl: "Insulin is first-line, McRoberts is first maneuver, OGTT at 6 weeks postpartum" — three sentences that resolve a large fraction of GDM/macrosomia questions.
— Setup: 32–36 week patient, fundal height 4+ cm > dates, possibly with risk factors
— Best next step: growth ultrasound (not immediate delivery, not cesarean scheduling, not amniocentesis)
— Setup: 38–39 week diabetic with EFW 4600 g
— Answer: offer scheduled cesarean delivery with documented shared decision-making
— Trap answers: routine vaginal delivery; induction of labor; cesarean for EFW 4100 g in non-diabetic
— Setup: GDM patient with fasting glucose 105 despite diet
— Answer: start insulin
— Trap answers: continue diet for another week; start glyburide as first-line; start metformin as first-line
— Setup: head delivers with turtle sign
— First action: call for help + McRoberts maneuver + suprapubic pressure
— Trap answers: fundal pressure; immediate forceps; immediate cesarean (Zavanelli is last resort)
— Setup: GDM patient at 6-week postpartum visit
— Answer: 75-g 2-hour OGTT
— Trap answers: fasting glucose only; HbA1c only; no further testing needed
— Setup: 4400 g infant of diabetic mother, glucose 32 at 1 hour, jittery
— Answer: IV D10 bolus + admit for monitoring
— Trap: oral feeding alone in symptomatic infant
— Setup: patient with prior 4500 g infant complicated by shoulder dystocia planning next pregnancy
— Answer: preconception weight loss, HbA1c, early first-trimester GDM screen, plan for elective cesarean if recurrence
— Setup: macrosomic infant with macroglossia, omphalocele, hypoglycemia
— Answer: genetics consult + Wilms tumor surveillance with renal ultrasound q3 months until age 8
Board pearl: Memorize the "first action" answers — McRoberts, insulin, ultrasound, OGTT — they crystallize the topic.
Macrosomia (EFW ≥ 4000 g) is managed by optimizing maternal glycemic control with insulin as first-line therapy, scheduling delivery by gestational diabetes class and control status, offering cesarean delivery at EFW ≥ 4500 g in diabetics or ≥ 5000 g in non-diabetics, preparing for shoulder dystocia with the HELPERR sequence starting with McRoberts maneuver, and closing the loop with a 75-g 2-hour OGTT at 4–12 weeks postpartum in every GDM patient.
Board pearl: The five Step 3 anchors — ultrasound when fundal height excess, insulin first-line, McRoberts first maneuver, no fundal pressure ever, postpartum OGTT at 6 weeks — answer the majority of macrosomia stems.