“Mapping Out” Prenatal Care - Brown University of prenatal care ... –History of PTB/symptomatic d/c: wet mount • HIV - All pregnant women should be counseled and offered test.

Belly Basics: “Mapping Out” Prenatal Care

Susanna Magee, MD MPH

Objectives

• Become familiar with the general

components of prenatal care

• Be able to recognize high risk conditions,

not necessarily treat them

• Develop ability to use our Centricity

prenatal care map as a tool to administer

and improve prenatal care

• Understand the importance of appropriate

documentation

First Trimester Objectives • Risk Assessment

– Intake visit with nurse, social worker and nutritionist

– History and Physical

– Intake labs including CF, Tay Sachs, MaterniT21 or Harmony where appropriate

• Health Promotion – Begin Prenatal vitamins/DHA/folate

– Counseling and Education, Immunizations

• Pregnancy Dating – Ultrasound for uncertain dating – Counsel on genetic screening options

History

• Review intake notes from

nurse, social worker, and

nutritionist (*L)

• Review patient

medical/surgical history

• Review past OB history

noting type of delivery,

gestational age, labor

duration, weight of infant,

maternal/infant

complications

History

• Paternal/Family History including h/o

congenital anomalies

• Medication Allergies/Anesthesia reactions

• Gyn Hx: Abnormal Pap Smears, cryo or

LEEP procedures

• Create Problem List, review and update

each visit

– where does this go? (*L)

Physical Exam

• Thorough head to toe exam

– Vitals

– General – obese? flat affect?

– Thyroid

– Breast exam

– CV - is there need for echo (pathologic) or is this just a flow murmur?

– Abdomen- scars

– Baseline reflexes

– Pelvic and Pelvimetry • Lost art

Physical

• Pelvimetry:

– Inlet = Obstetrical (true)

conjugate which is distance

from sacral promontory to

superior aspect of pubic

symphysis (10-12 cm).

– Mid = distance between

ischial spines (>10cm), note

sacral concavity and

inclination

– Outlet = pubic arch,

distance between ischial

tuberosities (8cm), coccyx

Physical

• DOCUMENT COMPLETE PHYSICAL

EXAM (*L)

First Trimester Labs

• Baseline CBC - check for anemia

• Blood Type ? Need for Rhogam – presence of D antigen on RBC means Rh+,

absence of D antigen means Rh -

• Antibody Screen - checks for antibodies against major and minor antigens on maternal RBC membrane – anti D antibodies means isoimmunization in

Rh( -) women

– Review other major/minor antigens like Kell/Duffy etc

– Pathologic vs. Non-pathologic

Labs

• Hepatitis B surface

antigen (HBsAg) to

check for Hep B

infection.

– Earliest detection

– + in active, chronic and

carrier state

– If positive, further

testing warranted

Labs

• Urine C & S

– Higher risk for UTI

– Remember to treat asymptomatic bacteriuria in

pregnancy.

• Controversy: how many colonies are bacteriuria

• Always get repeat UA/C&S as TOC after treatment

– Any GBS = prophylaxis in labor against GBS

– 2 UTIs or 1 pyelonephritis buys prophylaxis

against repeat infection

Labs

• Rubella antibody

• Syphilis screen (RPR, STS, VDRL)

– If positive, obtain confirmatory FTA-ABS

qualitative.

– If FTA-ABS positive, obtain quantitative

screening titer (RPR) and treat accordingly with

PCN

– Follow titers of RPR q 4-6 weeks

– Treat as indicated

Labs

• PAP, GC, Chlamydia, Wet mount (if

indicated) done at initial OB exam

– History of PTB/symptomatic d/c: wet mount

• HIV - All pregnant women should be

counseled and offered test. If patient

declines, document

• +/- Obtain Hgb electrophoresis

Labs

• For high risk patients, place PPD and read

in 48-72 hours. If positive (review

guidelines), check CXR.

– no need to delay xray

– If PPD+, CXR - : INH for 9 mo postpartum

(TB clinic starts about 3 months pp)

– Do not attribute +PPD to childhood BCG

vaccination

• Quantiferron gold

Labs

• Obtain intake 1 hour non fasting 50 g

glucose screen:

– history of abnormal glucose value or gestational

diabetes

– consider if multiple historical risk factors • family history

• prior macrosomia

• obesity

• congenital anomaly

• IUFD

Labs

• Toxoplasmosis, Varicella, CMV,

Parvovirus, HCV, HSV titers not routinely

recommended.

• Obtain UTOX in high risk patients,

especially if they present late for care,

frequently miss appointments or admit to

drug use.

– Follow up + UTOX at least q trimester

Vaccinations

• May give Hepatitis B, TdaP, and Influenza during pregnancy. – May start hepatitis series at intake.

– TdaP best given 28-36 week window to confer passive immunity to infant

– Influenza vaccine indicated for all pregnant woman regardless of gestational age during flu season (Oct - Mar)

Pregnancy Dating (more in the second trimester)

• Naegele’s Rule: EDD = FDLMP + 7d - 3m

• LMP

• Uterine size at intake

• Conception

• Ultrasound findings

• hCG levels

Pregnancy dating

LMP and u/s correlation

• 0-9 weeks +/- 4 days

• 10-13 weeks +/- 7 days

• 14+ weeks +/- 10 days

Counseling and Education

• Monthly visits

• Encourage breastfeeding right from initial

visit

– Definitively by 20 weeks

• Ensure safe environment/confirm supports

– Volunteer doula program

– Group visits

• Substance abuse counseling

Second trimester

Cruising along...

Second Trimester

• Definition: 12-24 weeks

• At and around 23-24 weeks, viability issues

– Importance of accurate dating

• Prenatal visits are typically every 4 weeks

Second Trimester

• 3 issues:

– Housekeeping

– Completing genetic

screening tests

– Establish dating

Housekeeping

Is the BTL signed and faxed to WOOD 2?

H and P done?

Intake?

Labs documented?

Is your name listed as provider?

Are previous deliveries entered?

Problem list updated?

Dating finalized?

Screening

• Discuss genetic testing with your patient

and DOCUMENT pt’s decision.

– What are the five screening tests?

– When should they be offered?

Prenatal Screening Tests

• Maternal serum markers and / or u/s findings to help

identify patients at risk for fetal malformations and

chromosomal abnormalities.

• Quad test includes a-fetoprotein (MSAFP), inhibin A,

unconjugated estradiol (uE3) and human chorionic

gonadotropin (hCG)

• AFP (most studied) is a protein made by the yolk sac, fetal

GI tract and fetal liver. Peaks in amniotic fluid by 12-14

weeks, detectable in maternal serum by 15-18 weeks

• Defect in fetal skin or fetal bleeding increases AFP in

amniotic fluid and therefore maternal serum

Prenatal Screening Tests

AFP

High levels, > 2.0 MoM (Multiples of the Mean)

may indicate the following:

neural tube defects, abdominal wall defects, impending fetal death,

multiple gestation, ectopic pregnancy, maternal hepatitis, herpes

infection, Rh disease, and fetal growth restriction

Low levels, < 0.25 MoM

• Suspect chromosomal abnormality

– primarily Down’s Syndrome (5%), molar pregnancy or

fetal demise

Genetic Screening

• MPSS

– MaterniT21

– Harmony

• Abnl ultrasound finding

• AMA

• H/O Trisomy in previous pregnancy

• Abnormal integrated screening

History of Spontaneous Preterm Birth

17 P

• Efficacy of Progesterone • 36.3 treatment vs. 54.9 % placebo delivered at < 37

weeks

• 20.6 vs 30.7% at < 35 weeks

• 11.4 vs 19% at < 32 weeks

– lower risk NEC, IVH and need for O2

– Most follow cervical length rather than screen

with FFN

History of Preterm Birth

FFN vs. cervical length

• FFN

– 22 and 34 and 6

– intact membranes

– < 3 cm dilation

– no intercourse or cervical manipulation within 24 hours

– fFn first--before other samples or manual cervical check

– high negative predictive value

• 1/1000 change delivery in 7 days if neg

• + predictive value poor, but as many as 14% will deliver within 2 weeks

Preterm Birth

• The incidental short cervix

– Vaginal progesterone

Third Trimester The homestretch

Third Trimester

• Definition: 24 weeks (viability) and beyond

• Number of Prenatal Visits

– Monthly until 28-32 weeks, then biweekly

visits at 32-34 weeks, and weekly after 36

weeks

• Continued Risk Assessment

– Domestic violence, symptoms of depression,

excessive weight gain, etc.

Third Trimester

Counseling/Visits

• 24-34 weeks – Repeat Risk Assessment…Update Problem List

• Consider influenza/hepatitis B vaccine

– Suggest prenatal classes / teaching ultrasound /

handouts

– Discuss breastfeeding, +/- circumcision, contraception

plans, home preparation, identify labor support

– Confirm fetal presentation

– Review dating

• VBAC-counseling high risk appointment at 32-34 weeks

• RCS-34 weeks

• BTL consents at 28 weeks FOR ALL PATIENTS

Third Trimester Labs

• Ensure previous trimester labs are complete

and documented!

• 26-28 weeks: 1 hour glucose screen (GDS2) • Order 3 hour screen (after the patient has followed a

high carb diet for 3 days) if 1 hour is > 130 (Carpenter &

Coustan)

– Repeat H & H

– Repeat STS in high risk women

– Repeat HIV GC Chlam in high risk women

• Defined by ACOG as all under age 25…..

Third Trimester Labs

• If pt. Rh -, time to order Antibody Titers

and give Rhogam (with 26-28 week labs)

– Order Rho Studies (on red lab sheet, check

Type and Screen, and Rho box)

– Lab will test maternal sample for anti-D Ab

• standard is 300 mcg

– Mom has 10 days to come in for shot

• If they miss, need to repeat the Rho studies to be

sure the dose of Rhogam is correct

Third Trimester Labs

– Standard dose Rhogam

is 300 mg, which

covers a 15 ml or less

mix of maternal fetal

blood.

– Rh Immunoglobulin

(Rhogam) is good for

12 weeks

Rh Special Situations

• If patient has vaginal bleeding in pregnancy

and is known to be Rh-, she should have

Rho studies and receive Rhogam

• If she presents days after the bleeding

occurred, then order Rho studies to see if

she has already produced anti-D Antibody

• If she has not, then give Rhogam – If she already had made anti-D Ab, then its too late to

give the Rhogam

Third Trimester Labs

• 35-40 weeks

– GBS vaginal rectal screen is recommended by

ACOG and AAFP for all pregnant patients at

35-37 weeks gestation

– Swab is considered interpretable for up to 5

weeks • If positive, PCN in labor

• If low risk PCN allergy: Ancef

• If high risk PCN allergy: sensitivities must be done to Clinda Erythromycin,

and Vancomycin

• If patient had GBS in urine during pregnancy, then requires Prophylactic Rx in

labor and no need vag/rectal swab

• Document your results and treatment plan

Third Trimester Labs

• You’re now at 40 weeks….what tests do

you recommend?

Third Trimester Labs

• Answer: NONE!

– No postdates testing is needed until pregnant

woman reaches 41 weeks unless there is some

other indication

• Decreased fetal movement

• Leaking fluid...

• What test should be done at 41 weeks?

Third Trimester Labs

• Answer: Best Evidence weighing cost

benefit ratio is for NST/AFI, otherwise

known as modified BPP

– Provides an immediate evaluation of fetal well-

being (NST) and uteroplacental function (AFI)

– What is an abnormal test?

• If NST abnormal (non-reactive, presence of deep or

prolonged variable decelerations, presence of late

decelerations)

• If AFI < 5 (5-8 considered low normal and will

require repeating in 2 days)

Third Trimester Labs

• What is the evidence?

– Has not been studied in a randomized

prospective fashion

– Miller et al 1996--largest and most respected

study

• Retrospective series of 15,482 high and low risk

pregnancies in which 56,617 MBPP’s were

performed as the initial fetal surveillance test

Miller et al, continued

• Positive Predictive Value (diagnostic accuracy of

an abnormal test to predict a compromised fetus)

– When applied to low risk conditions, the

positive predictive value is not very good

• Negative Predictive Value (diagnostic accuracy of

a normal test result to predict a healthy fetus)

– Comparable to the use of the BPP or CST, and

is much higher than the NST alone)

Miller et al, continued

• Evidence to date suggests that using NST

AFI together at 41 weeks, 41.5 weeks and

42 weeks results in a 50% decrease in the

rate of fetal demise after a normal test result

– 0.8 fetal deaths per 1000 versus 1.9 fetal deaths

in 1000)

• Note number of tragic outcomes very small

• There is no evidence to suggest that testing be done

before 41 weeks

Postdates….uggh!

• What do we do with this information?

– Once patient approaching 41.0 weeks, need to

discuss induction plan

– Plan should be documented and begin at 41+

weeks +/- and reviewed with the attending on

call

• “Stripping membranes”

– Some evidence that stripping at 37 weeks (term) prevents

the need for postdates management

How to determine ripening vs.

induction

• Bishop’s scoring

– Help assess the need for cervical ripening vs. straight

induction with oxytocin

– See form next page

Third Trimester Review

• Utilize the Prenatal Care Map

• Document Labs and Relevant Information

on the Problem List

• Your MCH Faculty are always available

– If they don’t know the answer, they’ll find it

out! Then everyone learns.

– Utilize OB Floor Preceptors in a Pinch

GET HELP

• Please precept your EDC

• Please precept your bimanuals/pelvimetry

• Please review your EDC and your labs each visit

• Print an OB Summary every trimester to be sure it is properly filled out

• If there are items not populating the care map contact Cathy Masterson.

ENJOY THIS EXPERIENCE

• Your hands may be the first ones to ever touch another

human being, even before their parents…