FUNDAMENTALS OF OBSTETRICS

Christine Pecci, MDAssociate Clinical ProfessorUCSF Department of Family and Community MedicineMarch 2018

No disclosures

OBJECTIVES

Review criteria for ultrasound vs LMP dating Review management of women at risk for

preterm delivery Describe guidelines for diagnosis, treatment and

management of: nausea and vomiting in pregnancy Preeclampsia gestational diabetes thyroid disease in pregnancy

List infections in pregnancy and how to manage or prevent these from occurring

Review Tdap recommendations in pregnancy

Tanya is a 23 yo G1P0 who presents for early pregnancy care. EGA 10 1/7 wks by a sure LMP

She had a visit to ED for nausea and vomiting Given 1 liter NS Electrolytes were normal TSH 0.1

NAUSEA AND VOMITING IN PREGNANCY

Nausea in 50-80% Vomiting/retching 50% Hyperemesis gravidarum 0.3-3%

Persistent vomiting Weight loss Ketonuria Usually electrolyte, thyroid, liver abnormalities

Lower rate of miscarriage

ACOG Practice Bulletin Jan 2018

TREATMENT OF N/V IN PREGNANCY

Multivitamin x 1 month before conception Ginger may decrease nausea Acupuncture/acupressure- no difference in RCTs

First line treatment pyridoxine +/- doxylamine Metoclopromide, ondansetron second line

Limited safety data, but overall risk low Oral corticosteroids used as last resort– avoid 1st

trimester

ACOG Practice Bulletin April 2015

NORMAL THYROID FUNCTION ANDPREGNANCY

Hcg stimulates TSH receptor, increasing thyroid production and decreasing TSH

Total thyroid hormone levels increase due to elevated thyroid-binding globulin (TBG)

Free T4 unchanged (direct assays ok but many labs use automated assays which can be inaccurate)

TSH is a reliable indicator of maternal thyroid status (American Thyroid Association) First trimester 0.1-2.5 mIU/L Second trimester 0.2-3.0 mIU/L Third trimester 0.3-3.0 mIU/L

HYPERTHYROIDISM IN PREGNANCY

Avoid meds in 1st trimester If medication needed, use PTU

risk of liver failure Risk face and neck cysts

Consider changing to methimazole after 16 wks(aplasia cutis) other congenital malformations

Smallest possible dose as medications Moniter TSH/T4 every 4 wks if on medication

HYPOTHYROIDISM AND PREGNANCY

50-85% need increase in thyroid replacement Preconception treat to <2.5 Should increase dose by 25-30% ASAP post

conception (can give two extra pills/wk)

Postpartum following delivery go back to pre-pregnancy dose and recheck in 6 wks

If Rx started in pregnancy with nl TSH reasonable to stop and recheck in 6 wks

SHOULD WE BE SCREENING FORHYPOTHYROIDISM? Case control trials showed hypothyroidism

associated with low IQ in the fetus RCTs do NOT confirm that treatment of

subclinical hypothyroidism improves neurocognitive outcomes Both initiated Rx after first trimester

Universal screening for thyroid disease in pregnancy is not indicated* Effectiveness of Rx not yet proven

*ACOG, Endocrine Society, American Association of Clinical Endocrinologists

INITIATING SUPPLEMENTATION

Treat if TSH >10 TSH>2.5 check TPO Ab status ?treat if TPO Ab+ and TSH >2.5 Don’t treat if TPO neg and TSH > upper nl <10

If treating Target lower half of preg specific range or <2.5

American Thyroid Association 2017

LMP VS. US DATING

Tanya also had an US done in the ED Crown-rump length = 9 2/7 weeks LMP 10 1/7 wks

6 days different than EDD based on LMP

Should you change her dating based on 1st

trimester US?

DATING

Gestational Age Discrepancy for re-dating w US date

< 9 weeks > 5 days (CRL)9 weeks to < 14 weeks > 7 days (CRL)14 weeks to < 16 weeks > 7 days (BPD, HC, AC, FL)16 weeks to < 22 weeks > 10 days22 weeks to < 28 weeks > 14 days28 weeks and beyond > 21 days

ACOG Committee Opinion Oct 2014

Single uniform standard based on expert opinion (ACOG, AIUM, SMFM)EDD=280 days after first day LMPHalf of women accurately remember LMP40% adjustment in 1st trimester; 10% adjustment 2nd trimesterUse earliest US

WILL MY BABY BE NORMAL? She has been reading about a new test for

making sure the baby is normal. She wants to know if you can order this test. Will having a normal test guarantee that this baby will be okay?

Characteristics of screening tests:T21

Dashe, Jodi MD Obstet Gyn 2016

Options for screening

First Trimester Second Trimesterhcg + PAPP-A hcg + AFP + estradiol + inhibin11-14 wks 15-22 wksCan be combined w NT Anatomy scanAFP in 2nd trimester for NTD Includes AFP

• 1st trimester screening gives the patient early results• 2nd trimester screening good for late entry to care• DON’T do both independently• CAN do combined (7 serum markers + NT)

CELL-FREE DNA Circulating DNA fragments placental in origin

from apoptotic trophoblasts Can be done anytime after 9-10 wks gestation Available in 7-10 days Best for trisomy 21 and 18 but also screens for

trisomy 13 and sex chromosome aneuploidies Gender Can be used as primary or secondary screening

AJOG June 2016 SMFM Consult Series

Dashe, Jodi MDObstet Gyn 2016

I’M SO NERVOUS… Tanya is worried specifically about preeclampsia

because her sister had it and needed to be induced a few weeks before her due date.

“Is there anything that you can give me so that I don’t get this disease too?”

PREECLAMPSIA: YOU WILL SEE IT! Incidence 2-8% Has increased by 25% in last two decades Risk factor for future CV and metabolic disease

Task Force for Hypertension in Pregnancy, 2013

INITIATE ASA 12-28 WKS FOR HIGH RISK

History of pre-eclampsia, esp if adverse outcome Multi-fetal gestation Chronic hypertension Diabetes type 1 or 2 Renal disease Autoimmune disease (SLE, APS)

Practice Advisory on Low-Dose Aspirin and Prevention of Preeclampsia: Updated Recommendations July 11 , 2016

CATEGORIES

Preeclampsia-eclampsia With or without severe features

Chronic hypertension Gestational hypertension- hypertension without

proteinuria after 20 week Chronic hypertension with superimposed

preeclampsia

Task Force for Hypertension in Pregnancy, 2013

PROTEINURIA

>300 mg in 24 hrs Spot urine:creatinine ratio > 0.3 Dipstick 1+

Proteinuria is classically part of the syndrome But NOT required to make diagnosis of

preeclampsia

DIAGNOSIS

Elevated BP >140/90 on two occasions 4 hours apart

Proteinuria or “severe features” >160/110 Plts <100K LFTs twice normal Persistent RUQ pain or epigastric pain Creatinine >1.1 or double Pulmonary edema New onset cerebral or visual disturbance

WHEN TO DELIVER?Diagnosis EGA MonitoringChronic htn 38 0/7Gestational htn 37 0/7 Weekly urine dip+BP+NSTPreE (not severe) 37 0/7 Biwkly dip+BP, wkly NST, labs q wkSevere PreE 34 0/7 In hospital

If severe uncontrolled htn, eclampsia, pulmonary edema, abruption, DIC, NRFHR, IUFD deliver after initial stabilization

INTRAPARTUM INTERVENTIONS

Mg with severe preeclampsia only Anti hypertensive meds only for > 160/110 Administer steroids prior to delivery if indicated

POSTPARTUM FOLLOW-UP

Check BP 72 hours post delivery and 7-10 days postpartum

Treat for >150/100 on two occasions 4-6 hrs apart Preconception- glycemic control, weight loss

ALL patients should receive education on warning signs

It’s a BOY!

The cervical length is 24 mm

ROUTINE US 18-22 WKS

Confirms dating if not already done Anatomy scan ? Cervical length

Universal screening not indicated

SCREEN FOR GDM AT 24-28 WKS

Overall incidence of DM in pregnancy 6%

90% of these are GDM Early screening- if

prior GDM, known impaired fasting glucose, BMI >30

GESTATIONAL DIABETES

HAPO trials show continuous relationship-neonatal hypoglycemia, macrosomia

Increased hyperbilirubinemia, operative delivery, shoulder dystocia

2010 International Association of Diabetes and Pregnancy Study Group (endorsed by ADA) (92, 180, 153) No data regarding therapeutic intervention

ACOG Practice Bulletin Feb 2018

DIAGNOSIS OF GDM 2010 International Association of Diabetes and

Pregnancy Study Group (endorsed by ADA) (92, 180, 153)

2013 NICHD recommends 2 step test (50 gm then 100 gm)

Consider prevalence of diabetes Consider resources One hour glucola: range 135-140fasting 1 hr 2hr 3hr

NDDG* 105 190 165 155CC** 95 185 165 140

*National Diabetes Data Group**Carpenter Coustan ACOG Practice Bulletin Feb 2018

MANAGEMENT AND TREATMENT

Diet + exercise + QID fingersticks Goal <140 on 1 hr and < 120 2 hr If fasting consistently >95, consider medication First line = Insulin (does not cross the placenta) Glyburide and metformin

Not approved but being used Glyburide crosses placenta but no measurable levels

in cord blood Metformin cross placenta and fetal levels similar to

maternal levels

ACOG Practice Bulletin Feb 2018

WHEN TO DELIVER? Induce at 39 weeks if pre-gestational or

gestational DM on meds For well controlled GDM without meds, unclear

whether induction is indicated

MODE OF DELIVERY WITH DIABETES

Prevention of a single permanent brachial plexus palsy Cesarean delivery for 4500 gm NNT 588 Cesarean delivery for 4000 gm NNT 962

POSTPARTUM FOLLOW-UP

15-50% with GDM develop DM 20+ years later Varies by ethnicity (60% Latina within 5 years)

Fasting or 2 hr GTT 4-12 wk postpartum IGT picked up by 2 hr

Repeat testing q 3 years if normal

INFECTIONS IN PREGNANCY

MAY I TRAVEL? Tanya wants to travel to Cancun- A friend of hers

lives in Mexico and is getting married. Tanya is 18 wks. What do you say? A. You should absolutely go! You are past the 1st

trimester so the fetus is fully formed and not at risk of being affected by Zika, a virus carried by mosquitos.

B. No way, mosquito repellents are toxic in pregnancy so you can’t protect yourself from bites.

C. Is your partner going too? You can go as long as you are not travelling alone.

D. How good of a friend is this?

ZIKA VIRUSTransmitted by Aedes species of mosquitos Incubation period 3-12 daysSymptoms 2 or more of following

-fever, rash, arthralgia or conjunctivitisCan be transmitted in all trimestersSexual transmission has been documented via semenPrior infection confers immunity

https://www.cdc.gov/pregnancy/zika/index.html

ZIKA AND FETAL CONCERNS

Microcephaly (<3%) Congenital Zika Syndrome

Severe microcephaly where skull partially collapsed Specific pattern of brain damage and decreased brain

tissue Damage to back of eye Congenital contractures (club foot, arthrogryposis) Hypertonia

BACK FROM CANCUN! Tanya reports that the wedding was one of the

most memorable events in her life and she is grateful that you supported her travel. She used DEET, wore clothes penetrated with permethrin and slept under a mosquito net. What do you need to ask her now? A. How are you feeling? B. Are you using condoms with your partner? C. Are you planning on going to visit your newly

married friend again during your pregnancy?

TEST if symptomatic

HSV Genital herpes affects 20% women in US? Incidence of new infection in preg 2% Women with recurrent HSV-75% can expect

episode during preg, 14% at delivery 80% of infected infants born to women with no

reported history 20% neonatal survivors have long-term

neurosequealae

HSV-GIVE PROPHYLAXIS AT TERM

Primary infection transmission - 30-60% at delivery Recurrent infection transmission 3% at delivery; no

lesions 2/10,000 Acyclovir, famcyclovir, valcyclovir all class B, most

data on acyclovir Routine screening not recommended Genital Sx or lesions- c/s decreases transmission from

7.2% to 1.2% even after ROM

Acyclovir 400 mg TID @ 36 weeks til delivery

HIV Opt out screening for ALL women Low threshold for repeating in third trimester Offer testing on L&D for high risk women without an

appropriately timed HIV test Early viral suppression is of upmost importance Elective cesarean if VL >1000 near delivery Intrapartum AZT unless consistent VL <1000 Neonatal AZT prophylaxis required for 4-6 weeks

add if NVP high risk Consider offering presumptive treatment (AZT+NVP+3TC)

No breastfeeding (developed countries) Clinician Consultation Center Perinatal hotline 24/7

http://nccc.ucsf.edu/

GBS Screen all women at 35-37 wks, unless

Previous child with early onset GBS disease GBS bacteruria in index pregnancy

Treat with intrapartum IV penicillin first line Ask for sensitivities if has pcn anaphylaxis to see if

can give Clinda/erythro Cefazolin if no anaphylaxis reaction to penicillin Vanco reserved for those with anaphylaxis or those

without sensitivities Adequate treatment >4 hours pcn or cefazolin

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RUBELLA

Do not give during pregnancy and avoid pregnancy x 28 days

Not an indication for termination If lab evidence of immunity, no need to repeat If neg or equivocal titer after 1-2 doses, give third dose

and stop checking titers Ok for children of pregnant women to get May give with Rhogam, check titer in 3 months

MMWR June 2013

VARICELLA

Lab evidence of immunity or disease

Birth in US before 1980 is not sufficient for pregnant women

Diagnosis or verification of history of varicella or zoster by health care provider Should have link to a typical

case or lab confirmation if testing done during acute infection

Tanya declined the Tdap and flu shot pregnancy because she was afraid of it hurting the baby.

Postpartum she is willing to accept these two immunizations if you still recommend them. She got the flu shot last season and got a Tdap after her last pregnancy in 2011.

Which immunizations would you give her?

TDAP IN EACH PREGNANCY

Tdap is indicated in EVERY pregnancy 27-36 wks EGA for transmission of antibodies to fetus

Once baby is out, indication for Tdap is based on maternal indications; she is up to date

Flu shot is indicated

SUMMARY

Establish accurate dating Provide primary care

Immunizations, healthy lifestyles Watch for pregnancy related diseases

Translates to risk of these diseases later in life We have interventions to prevent perinatal

transmission of disease Zika- Travel advisory HSV- Acyclovir HIV- HARRT GBS- Penicillin