OB- Pregnancy & Fetal Complications

What confirms the diagnosis of gestational HTN?

Complete resolution of HTN at 12 weeks postpartum

What is classified as chronic HTN

BP ≥ 140/90 before pregnancy OR

before 20 weeks gestation OR

newly dx HTN that onset after 20 wks gestation & persists > 12 wks PP

What is classified as mild chronic HTN?

≥ 140/90

What is classified as moderate chronic HTN?

≥ 150/100

What is classified as severe chronic HTN?

≥ 160/110

What is the treatment for mild chronic HTN?

Monitor q 2-4 wks in office until 34w, then q weekly

Delivery at ≥ 37 wks

What is the treatment for moderate-severe chronic HTN?

Methyldopa (DOC), labetalol, hydralazine, nifedipine

Delivery 37-38 wks depending on maternal BP & NSTs (start 3rd trimester)

What meds should NOT be used to treat chronic HTN in pregnancy?

ACE/ARBS or diuretics

What are other names for gestational HTN?

Transient HTN of pregnancy or pregnancy induced HTN (PIH)

What is gestational hypertension / PIH?

New HTN in pregnancy onset after 20 wks gestation & normotensive by 12 wks PP & no evidence of proteinuria

What is the goal BP for gestational HTN?

SBP < 160

DBP < 110-105

What is the treatment for gestational HTN?

Lifestyle changes first, add hydralazine or labetolol if uncontrolled

What is pre-eclampsia?

New onset HTN ≥ 140/90 after 20 wks gestation PLUS proteinuria and resolves w/ delivery

What is classified as proteinuria in pregnancy / pre-eclampsia?

≥ 300 mg/24h or > 1+ on UA

When can pre-eclampsia be diagnosed if HTN onsets before 20wks ?

Multiple gestations or molar pregnancy

What is the MCC of pre-eclampsia?

Placental ischemia secondary to cytotrophoblast invading the spiral arteries

What are potential complications of preeclampsia?

Uterplacental ischemia which causes placental abruption, coagulopathy, thrombocytopenia, stroke, pulm edema, sub capsular liver hematoma, retinal detachment, IUGR, prematurity

Pre-eclampsia is considered severe when ≥ 1 of what features are present?

BP ≥ 160/110 on 2 occasions 6 hrs apart while on bed rest

Proteinuria ≥ 5 g/24hr or ≥ 3+ on 2 UA’s atleast 4 hrs apart

Oliguria < 500 ml/24hr

Cerebral or visual disturbances

Pulm edema or cyanosis

Epigastric or RUQ pain

Elevated LFTs

ITP - < 100,000 plts/mm³

Fetal growth restriction

What is a variation of severe pre-eclampsia that can result in DIC which is often fatal?

HELLP syndrome → hemolysis, elevated liver enzymes, low plts

What is the pathophysiology of HELLP syndrome?

Elevated BP → endothelial injury → clotting cascade → fibrin/plts deposited in liver & clogs flow → liver damage & depleting plt stores

RBCs break down passing through damaged blood vessels → hemolysis

What are RF for HELLP syndrome?

Maternal age > 34, multiparous, poor prenatal care

What should be done for HELLP syndrome?

Hospitalize & consider urgent delivery if unstable

What is considered chronic HTN w/ superimposed pre-eclampsia?

Pt w/ chronic HTN & ≥ 1 of the following:

New onset proteiura

HTN w/ proteinuria before 20 wks

Sudden inc in proteinura present before pregnancy

Sudden inc in BP that was well controlled

Thrombocytopenia < 100,000 plts/mm

Elevated LFTs - ALT or AST

What is eclampsia?

Tonic clonic seizures (focal or generalized) w/ postictal state or coma in the pre-eclamptic pt not attributable to other causes

When do most cases of eclampsia present?

Third trimester (most intrapartum or w/in 48 hrs after delivery)

The following ssx are seen with what condition?

• HTN

• Edema (proteinuria → dec serum protein & oncotic pressure → swelling)

• ± frothy urine

• Severe: HA, vision changes, oliguria, RUQ pain

Pre-eclampsia

What signs and symptoms are seen with eclampsia?

Pre-eclamptic features PLUS seizures, coma, hyperreflexia

What is the workup for pre-eclampsia?

At home BP monitoring & log, CBC w/ diff, CMP, PT/PTT, LDH, UA dips at interval prenatal visits, & 24 hr urine

What is best for the diagnosis of pre-eclampsia?

24 hr urine → > 300 mg in mild or ≥ 5 g in severe

What is the treatment for mild pre eclampsia if < 34 wks?

Conservative, bed rest, record daily weight & BP, weekly UAs, ± BP meds, antenatal steroids & plant for elective delivery (22-33 wks gestation)

*goal: < 160/110-105

What is the treatment for mild pre-eclampsia if ≥ 37 wks?

Deliver

What is the treatment for eclampsia?

ABCDs

Mag sulfate for seizures (lorazepam if refractory)

BP meds- hydralazine > labetalol

Deliver once stabilized

What is pregnancy induced glucose intolerance that usually resolves PP but puts the mother at an increased risk of developing T2DM?

*50% risk in 5 yrs if insulin required, 60% risk in 15 yrs if dietary control

GDM

What causes gestational diabetes (GDM)?

Placental release of human placental lactose, cortisol, human growth hormone and corticotropin releasing hormone → antagonizes insulin → insulin resistance & increasing glucose

What are RF for GDM?

Excessive weight gain during pregnancy (greatest RF & controllable), FHx or PHx, obesity prior to pregnancy, prior fetus weighing > 9lbs, AA/hispanic/Native American, multiple gestations or twins, hx spontaneous abortions or stillbirth

What fetal risks are associated with GDM?

Macrosomia which leads to birth comps & shoulder dystocia, IUFD/stillbirth, polyhydramnios, hypoglycemia, polycythemia, hypocalcemia, hyperbilirubinemia

What maternal risks are associated with GDM?

DKA, placental abruption, pre-eclampsia, T2DM, recurrence w/ subsequent pregnancies

When is screening for GDM performed?

24-28 wks w/ 50g OGTT non-fasting

What should be done if a GDM screening is positive?

Send for confirmatory / diagnostic fasting 3 hr OGTT

What aggressive screening for GDM would pts with a BMI > 34 or 40 and a PHx GDM requiring insulin prior to pregnancy benefit from?

24-28 wks 3hr OGTT, HgbA1C, random glucose, fasting glucose

What is a class A1 GDM?

Glucose can be controlled w/ diet alone

What is a class A2 GDM?

Insulin is required for control

What is considered a positive 3 hr OGTT test?

Atleast 2 abnormal values

*fetal macrosomia & other effects can be seen w/ only 1 abnormal value

What is the non-rx treatment for GDM?

Daily glucose checks (fasting < 100, 1 hr post prandial < 130-140, 2 hr post prandial < 120)

Diet & exercise mods

When is pharmacological medication indicated for GDM?

Fasting BG > 100 or postprandial > 140 w/ lifestyle changes

Insulin (DOC), glyburide, metformin

What oral hypoglycemic medication does not cross the placenta but increases the risk of eclampsia?

Glyburide

What antenatal testing is indicated in GDM?

Level II US 18-20w (fetal anatomy scan), weekly or biweekly NST at 32-36w or BPP, f/u US for growth every 3-4w, doppler flow of umbilical vessels for IUGR

How is labor managed with GDM?

Inidicated at 39w for insulin dependent

38w if uncontrolled or macrosomia

C-section if EFW > 4500g

Glucose control in labor

When is there an increased risk of GBS infx transmission?

Prematurity, maternal intrapartum fever > 100.4°F, prolonged ROM, prior infant w/ GBS, GBS bacteriuria

What is a maternal infection of the urogenital tract and/or rectom that is a significant source of neonatal morbidity/mortality d/t potential for horizontal transmission to fetus when passing through birth canal?

GBS

What can a fetal GBS infection result in?

Meningitis, PNA, or sepsis

How does early onset fetal GBS infection present?

Occurs in first 7 days (MC first 2), causes septic shock, resp distress or meningitis

What is the presentation of late onset GBS?

May be from maternal genital tract or nursery personnel, MC presentation is meningitis (50% have permanent neuro injury)

*prevention strategies not effective in this cohort

When is the GBS rectovaignal swab completed in pregnancy?

*not required if abx prophylaxis is already required

36-37 wks

When is GBS antibiotic prophylaxis indicated?

GBS + urine culture results at anytime during current pregnancy OR prior baby w/ GBS

What prophylactic antibiotics are used for GBS at the time of delivery?

PCN G IV OR Ampicillin IV

PCN allergy → get a sensitivity w/ culture; use clinda or erythroIV

PCN allergy + resistance → Vanco IV

What are the 5 congenital infx passed from infected mother to her fetus that present similarly, involving the heart, skin, eye, ear, and CNS (can cause chorioretinitis, microcephaly, & focal cerebral calcifications)?

Toxoplasmosis

Other infx (HBV, syphilis, Parvo B1s, zika)

Rubella

CMV

HSV

What viral infection is from the togavirus family, is considered a disease of childhood & may be vertically transmitted (hematogenously) via placenta?

Rubella virus

When is the risk of rubella transmission the greatest/

Maternal infx acquired in first 4 wks after conception (MC in unvaccinated)

How does a maternal rubella infection present?

Flu like sx, posterior cervical & auricular LAD, widely distributed erythematous maculopapular non pruritic rash; photosensitivity & jt pain (MC in young women)

How does a congenital rubella infection present?

Deafness (MC), vision impairment, neurological defects, heart defects, mental retardation & microcephaly

*intrauterine dx by US

How can rubella congenital infx be prevented?

Screen during preconception counseling, vaccinate before conception, immediate vaccination postpartum for those w/ no immunity or equivocal titers

What congenital viral infx has no vaccine, routine screening is not reliable, & can be vertically transmitted via placenta (MC in immunocompromised)?

*handwashing is best prevention

CMV

How does CMV maternal infx present?

MC asx, mono like illness, fatigue, malaise, LAD, low grade fever

*no official tx, consider ganciclovir

How does congenital CMV infx present?

Sensorineural hearing loss, chorioretinitis, microcephaly, blueberry muffin rash (TTP), petechia

*dx on US → abnormal brain development

Is a congenital varicella infx (of HHV family) linked to active primary maternal infx “chickenpox” infection or by recurrent infection “shingles”?

Chickenpox

How does maternal varicella (adult onset) present?

More likely to cause PNA

* immunity checked by serum IgG to confirm infx if no hx of dz or vaccine

When is the greatest risk of fetal varicella congenital infx?

First 4 months of pregnancy; can cause limb hypoplasia, cutaneous scarring, menstrual (lol I think she meant mental) retardation, CNS abnorms

What viral congenital infection, referred to as fifth disease” is not routinely screened for in pregnancy, in which vertical transmission may result in fetal hydrops and fetal demise?

Parvovirus B19

How does a parvovirus maternal infx present?

Flu like sx, arhtropathy/arthralgia

How does a parvovirus congenital infx affect the fetus?

Target & infect reticulocytes → hemolytic anemia & halts erythropoiesis → hydrops fetalis in utero

What protozoan infection is transmitted primarily through infected meat or food contaminated by cat or ferret feces and is prevented by avoiding stray cats, cat litter, raw meat, & washing fruits and vegetables?

Toxoplasmosis

How does a maternal toxoplasmosis infx present?

Often asx, +/- mono like illness

*maternal tx w/ spiramycin ± sulfadiazine & aggressive tx of fetus at birth

How does a fetal toxoplasmosis infx present?

Microcephaly, intracranial calcifications, hearing loss, HSM

*dx w/ US

What congenital infection is caused by a flavivirus, is vector borne (Aedes mosquito) & sexually transmitted, causes microcephaly and IUGR in utero and has no treatment?

Zika virus

What is there an increased risk of if a mother contracts COVID during pregnancy & PNA?

Preterm birth < 37 wks & C- section

What happens when an Rh- mother has exposure to Rh+ RBC antigens, like in pregnancy (iso/alloimmunization)?

IgM anti-Rh antibodies form first, do NOT cross placenta → first pregnancy unaffected

IgG antibodies cross placenta barrier with the next pregnancy & destroy fetal RBCs → erythroblastosis / hydrops fetalis

When does Rh isoimmunization occur?

Possible w/ 0.1mL fetal blood entering maternal circulation; can occur at any point in pregnancy but MC at delivery

How is Rh isoimmunization prevented with passive immunization in a term pregnancy?

300 mcg RhoGAM given at 28wks & w/in 72hrs of delivery

How is Rh isoimmunization prevented with a 1st trimester abortion or miscarriage?

50 mcg MICRhogam

What is a serious fetal condition of abnormal accumulation of fluid in ≥2 fetal compartments (ascites, pleural effusion, etc) that can be immune (isoimmunization) or non-immune (infection)?

Hydrops fetalis

What conditions cause hydrops fetalis?

Rh disease & parvovirus B19

What are normal Hgb values during pregnancy?

1st & 3rd trimester: ≥ 11

2nd trimester: ≥ 10.5

What kind of anemia?

• hypo chromic, microcytic

• dec serum iron, ferritin, transferrin

• inc TIBC

• tx w/ supplements

Iron deficiency anemia

What should you NOT supplement in thalassemia (impaired rate of hemoglobin production)?

Iron

In what patients should sickle cell screening be offered to?

(screen w/ hgb electrophoresis & prenatal genetic carrier screening at first visit)

African, mediterranean, & southeast asian

*genetic counseling if both parents are carriers

What is EFW below the 10th percentile for GA, diagnosed by US or size/date discrepancy on PE?

Intrauterine growth restriction (IUGR)

What is a birth weight over 4000 g (top 10% of babies born in US)?

Macrosomia

What are complications of macrosomia?

Shoulder dystocia, inc risk c section

What are the largest RF for macrosomia?

Elevated preconception BMI & excessive maternal wt gain

also: GDM, multiparty, prior history & post term gestation

What is pregnancy loss after 20w or 500g?

Intrauterine fetal demise

How is intrauterine fetal demise diagnosed?

Maternal reports of decreased/absent fetal movements, absence of heart tones, US (most definitive → no heartbeat, no movement)

What is the treatment for intrauterine fetal demise?

Try to identify cause, pathology, delivery (typically by IOL); delivery of a stillbirth

What is a post-term birth?

Pregnancies that continue 14 days past EDD

*biweekly monitoring NST starts at 41w, assess AFI

What risks are associated with post-term birth?

Fetal macrosomia & increase mortality rate after 41w

What is the treatment for post-term birth?

IOL → assess cervix bc strongly associated with probability of success (Bishop score > 8)

What can be used for induction of labor (IOL)?

Oxytocin, PGs (misoprostol, cervidil), artificial ROM

What risks are associated with vaginal birth after cesarean (VBAC)?

Uterine rupture, perinatal death or permanent injury to fetus, & inc risk of need for cesarean

Who are candidates for VBAC?

Only 1 prior c-section (allow 12-18 months before attempting), lower transverse uterine incision, & obstetrician immediately available on unit w/ anesthesia & nursing staff for emergency section

What is the safest outcome for a baby in a mother who previously had c-sections?

Repeat c-section