Comprehensive Handbook Obstetrics & Gynecology 3rd Ed

By Thomas Zheng

The 3rd Edition is completely updated to reflect the latest recommendations, including the 2020 risk-based cervical cancer management guideline. It provides vital information in a concise, portable format. The handbook focuses on diagnosis and therapy, including management protocols, medications, and dosages. Common problems are covered in greater detail. Key facts on uncommon conditions are also presented. Medical students and interns can find pearls on performing examinations of the pelvis, breast, and cervix. Illustrated techniques and procedures include knot-tying, instrument use, perineal laceration repair, amniocentesis, and measurement of AFI and cervical length. This handbook also includes thirteen operative dictations, which describe common procedures with the latest techniques.

• Language: English
• Publisher: BookBaby
• Release date: Apr 24, 2021
• ISBN: 9780982267783

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Comprehensive

Handbook

Thomas Zheng, MD

Comprehensive

Handbook

3rd Edition

Contents

Author’s Note III

Abbreviations IV

OBSTETRIC TRIAGE 1

Obstetric Triage Acuity 1

Term Labor Admission 2

Preterm Labor or Contractions 3

Rupture of Membranes 4

Vaginal Bleeding 5

Decreased Fetal Movements 6

Hypertension 7

Trauma in Pregnancy 8

Cardiac Arrest 8

LABOR AND DELIVERY 10

Intrapartum Fetal Monitoring 10

Analgesia and Anesthesia 19

Normal Labor and Delivery 22

Labor Interventions 34

Perineal Laceration and Episiotomy 37

Induction of Labor 43

Group B. Streptococcal Prophylaxis 46

Operative Vaginal Birth 49

Cesarean Birth 54

Shoulder Dystocia and Macrosomia 58

Vaginal Birth after Cesarean 62

External Cephalic Version 64

Neonatal Assessment 66

POSTPARTUM CARE 70

Postpartum Hemorrhage 70

Postpartum Fever 77

Routine Postpartum Care 78

PRENATAL CARE 83

Maternal Physiology 83

Routine Prenatal Care 84

Nausea and Vomiting of Pregnancy 89

Aneuploidy Screening 91

Prenatal Diagnosis 93

Drugs and Radiations in Pregnancy 96

Ultrasound in Pregnancy 98

OBSTETRIC COMPLICATIONS 106

Antepartum Testing 106

Amniotic Fluid Disorder 109

Fetal Growth Restriction 111

Stillbirth 113

Preterm Labor 116

Prelabor Rupture of Membranes 121

Indicated Early Birth 123

Cervical Insufficiency and Cerclage 125

Placental Abruption 127

Placenta Previa 129

Multifetal Gestations 133

Alloimmunization 137

Pregnancy Termination 140

COMPLICATED PREGNANCY 142

Hypertension and Preeclampsia 142

Eclampsia 149

Chronic Hypertension in Pregnancy 150

Heart Disease 152

Venous Thromboembolism 156

Thrombophilia in Pregnancy 158

Respiratory Diseases 161

Gestational Diabetes Mellitus 165

Pregestational Diabetes 172

Thyroid Diseases in Pregnancy 175

Hematologic Disorders 177

Neurological Disorders 181

Psychiatric Disorders 184

Rheumatic Diseases 188

Acute Abdomen in Pregnancy 190

Gastrointestinal Diseases 192

Intrahepatic Cholestasis of Pregnancy 194

Skin Disorders 196

Urinary Tract Disorders 197

Perinatal Infections 199

HIV Infection 203

GENERAL GYNECOLOGY 205

Contraceptive Overview 205

Hormonal Contraception 215

LARC and Sterilization 219

Well-Woman Visit 225

Breast Cancer Screening 228

Breast Diseases 231

Cervical Cancer Screening 235

Vaginitis 244

Sexually Transmitted Diseases 250

Pelvic Inflammatory Disease 259

Ectopic Pregnancy 262

Early Pregnancy Loss 269

Acute Pelvic Pain 274

Chronic Pelvic Pain 276

Pediatric Gynecology 278

Uterine Leiomyoma 281

Abnormal Uterine Bleeding 286

Adnexal Mass 291

Benign Vulva Disease 295

Female Sexual Dysfunction 299

Hysterectomy 300

Perioperative Care 304

REPRODUCTIVE ENDOCRINOLOGY AND INFERTILITY 314

Reproductive Physiology 314

Puberty 316

Amenorrhea 318

Primary Dysmenorrhea 322

Endometriosis 323

Premenstrual Syndrome 326

Polycystic Ovarian Syndrome 328

Menopause 331

Osteoporosis 336

Infertility Evaluation 339

Management of Female Infertility 343

Assisted Reproductive Technology 349

PELVIC FLOOR DISORDERS 353

Urinary Incontinence 353

Pelvic Organ Prolapse 358

Fecal Incontinence 366

Fistula 367

GYNECOLOGIC ONCOLOGY 369

Gestational Trophoblastic Diseases 369

Cervical Cancer 374

Endometrial Cancer 379

Ovarian Cancer 385

Nonepithelial Ovarian Tumors 390

Vulvar and Vaginal Cancer 394

Chemotherapy 398

SURGICAL TECHNIQUES 402

Basic Instruments 402

Sutures 406

Knots 408

Endoscopy 412

OPERATIVE DICTATIONS 415

Cesarean Delivery 415

Vacuum-assisted Vaginal Delivery 416

Forceps-assisted Vaginal Delivery 417

Shoulder Dystocia 418

Postpartum Bilateral Tubal Ligation 420

Laparoscopic Tubal Fulguration 421

Dilation and Curettage 423

Hysteroscopy 424

Laparoscopic Salpingectomy for 425

Ectopic Pregnancy 425

Total Abdominal Hysterectomy 427

Total Vaginal Hysterectomy 428

Laparoscopic Assisted Vaginal Hysterectomy 429

Total Laparoscopic Hysterectomy 431

RESEARCH DESIGN 433

REFERENCE BOOK LIST 436

SPANISH 437

Comprehensive Handbook

Obstetrics & Gynecology

3rd Edition

Thomas Zheng, MD

Department of Obstetrics and Gynecology

Valleywise Health/District Medical Group

Phoenix, Arizona

Clinical Associate Professor of OB/GYN

University of Arizona College of Medicine-Phoenix

Comprehensive Handbook Obstetrics and Gynecology, 3rd Edition, ePub

ISBN-10 : 0982267789

ISBN-13 : 9780982267783

Copyright © 2021 by Phoenix Medical Press LLC

Previous editions, © 2009 and 2012 by Phoenix Medical Press LLC

All Right Reserved

10335 N. 49th Place

Paradise Valley, AZ 85253

Email: [e-mail]

Reviewers

Mike Brady, MD

Residency Program Director, Department of OB/GYN, Creighton University School of Medicine-Phoenix at Valleywise Health and Dignity-St. Joseph’s Hospital

Professor of Creighton University SOM Clinical Associate Professor of University of Arizona COM-Phoenix

Linda Chambliss, MD, MPH

Professor of OB/GYN, Creighton University School of Medicine

Clinical Professor, University of Arizona School of Medicine-Phoenix

Dean V. Coonrod, MD, MPH

Chair, Department of OB/GYN, Valleywise Health/District Medical Group

Professor & Chair, Department of OB/GYN, Creighton University School of Medicine Regional Campus

Professor of University of Arizona College of Medicine-Phoenix

Heather Dalton, MD

Assistant Professor

Division of Gynecologic Oncology

University of Arizona College of Medicine

Creighton University School of Medicine-Phoenix

Arizona Oncology (US Oncology Network)

Nita Desai MD, MBA

Chief and Fellowship Director– Division of Advanced GYN Surgery & Pelvic Pain

Vice Chair, Academic Department of OB/GYN, Dignity-St. Joseph’s Hospital and Medical Center

Assistant Professor, Creighton University School of Medicine-Phoenix

Michael R. Foley, MD

Professor and Chair

Department of Obstetrics and Gynecology

Banner – University Medical Center Phoenix, University of Arizona College of Medicine- Phoenix

Gregg Giannina, MD

Director of Maternal Fetal Medicine

Department of OB/GYN

St. Peter’s University Hospital

New Brunswick, NJ

Kendra M. Gray, DO

Maternal Fetal Medicine Fellow

Department of Obstetrics and Gynecology

Banner – University Medical Center University of Arizona College of Medicine- Phoenix

David L. Greenspan, MD

Clinical Associate Professor

Obstetrics, Gynecology and Pathology

University of Arizona College of Medicine-Phoenix

Ian Komenaka, MD

Breast Surgeon, Department of Surgery

Valleywise Health/District Medical Group

Associate Professor of Clinical Surgery, University of Arizona College of Medicine

Associate Professor of Surgery, Creighton University School of Medicine

Paul M. Magtibay, MD

Professor and Chair

Department of Medical & Surgical Gynecology

Mayo Clinic Arizona

Elyssa Metas, MD

Department of OB/GYN, Valleywise Health/

District Medical Group

Global Women’s Health Fellow, Creighton

University School of Medicine - Phoenix

Bradley J. Monk, MD

Professor, Division of Gynecologic Oncology

Arizona Oncology (US Oncology Network)

University of Arizona College of Medicine

Creighton University School of Medicine-Phoenix

Abraham Nick Morse, MD, MBA

Assistant Professor of Obstetrics and Gynecology

Department of OB/GYN

Tufts University School of Medicine Boston, MA

Linda R. Nelson, MD, PhD

Professor of OB/GYN

University of Arizona College of Medicine-Phoenix

Professor of Clinical OB/GYN

Creighton University School of Medicine-Phoenix

Travis Powell, MD

Department of OB/GYN, Valleywise Health/District Medical Group

Assistant Professor, University of Arizona College of Medicine and Creighton University School of Medicine

Sonam Singh, MD

Department of OB/GYN, Valleywise Health/District Medical Group

Assistant Professor, University of Arizona College of Medicine and Creighton University School of Medicine

Lingjin Zheng, MD

Resident, Psychiatry

Washington University School of Medicine in St. Louis

Notice

Although the information in the handbook is carefully compiled by the author from various reputable sources and reviewed by at least two experts in the respective fields, the accuracy and completeness cannot be guaranteed. The author, reviewers, and publisher are not responsible for any liability or injury that may arise from using the handbook. This handbook is designed as a convenient pocket guide for busy clinicians and is not intended to replace any textbooks, journals, or other information sources.

Author’s Note

No man’s opinions are better than his information. Paul Getty (1960)

The quote above is on the plaque that I received at my graduation from the Phoenix Integrated Residency in OB/GYN (PIROG). The Department of Family Medicine kindly gave me the Best Consulting Obstetrician/Gynecologist Award. Whether as a resident or as an attending physician, I always try to provide the latest and unbiased information to patients and colleagues.

OB/GYN practice is complex. There is no way we can remember everything, and I still reference this handbook daily. Every time I go to clinic, I double check to make sure it is in my pocket. When I learn something new or useful, I add it to the handbook.

This handbook is derived from the PIROG Manual that I put together for the residents and medical students. Although many excellent textbooks, manuals, and websites are available, none of these sources adequately address the daily needs of residents and students in a pressured environment. This handbook is no magic bullet either. Let me put it this way: It may function like 325 mg of Tylenol to ease your pain and provide you some comfort.

Since the first edition was published in 2009, the handbook has been well received. Hearing the kind words and encouragement of my readers motivated me to do an even better job with the new edition. Now the third edition is finally here! It is a big improvement over the second edition in every aspect. An immense effort has been made to maximize its content throughout the writing and design process. I hope it will help guide you through many busy rotations and sleepless nights.

I would like to thank all the reviewers for their continuous feedback and edits. Their suggestions have enriched the book content. I also want to recognize all the individuals who contributed to the very first edition of the PIROG Manual and helped me throughout my residency.

Special thanks goes to our readers. You are the ones who keep this project going. Please contact me at [e-mail] if you see any errors or have any suggestions.

Thomas Zheng, MD

Phoenix, Arizona

Abbreviations

↑: increase

↓: decrease

+: positive

–: negative

Δ: change or trimester

AB: abortion

ABG: arterial blood gas

AC: abdominal circumference

ACOG: American College of Obstetricians and Gynecologists

ADA: American Diabetes Association

AFI: amniotic fluid index

AGC: atypical glandular cells

AGC-NOS: atypical glandular cells not otherwise specified

AHA: American Heart Association

AIS: adenocarcinoma in situ

AJOG: Am J Obstet Gynecol

AMA: advanced maternal age

AROM: artificial rupture of membrane

ART: assisted reproductive technologies

ASA: aspirin or American Society of Anesthesiologists

ASCCP: American Society for Colposcopy and Cervical Pathology

ASC-H: atypical squamous cells cannot exclude HSIL

ASCUS: atypical squamous cells of undermined significance

AUB: abnormal uterine bleeding

BID or bid: twice a day

BMI: body mass index

BMS: bone marrow suppression

BP: blood pressure

BPD: biparietal diameter

bpm: beats per minute

BPP: biophysical profiles

BSO: bilateral salpingo-oophorectomy

BTL: bilateral tubal ligation

BV: bacterial vaginitis

CBC: complete blood count

CEFM: continuous electronic fetal monitoring

CD: cesarean delivery

CHD: coronary heart disease

CIN: cervical intraepithelial neoplasia

CKC: cold knife cone

CMP: complete metabolic panel

CNS: central nerve system

CO: ACOG Committee Opinion

CPD: cephalopevic disproportion

Cr: creatinine

CRL: crown rump length

CST: contraction stress test

CV: cardiovascular

CVS: chorionic villus sampling

CXR: chest x-ray

D5W or D5NS: dextrose 5% in water or normal saline

d: day

D/C: discontinue

D&C: dilation and curettage

DEXA: dua-energy x-ray absorptiometry

DM: diabetes mellitus

DUB: dysfunctional uterine bleeding

DVT: deep vein thrombosis

Dx: diagnosis

EBL: estimated blood loss

ECC: endocervical curettage

ECV: external cephalic version

EDC: estimated date of confinement

EDD: estimated date of delivery

EE: ethinyl estradiol

EF: ejection fraction

EFM: electronic fetal monitoring

EFW: estimated fetal weight

EGA: estimated gestational age

EMB: endometrial biopsy

fFN: fetal fibronectin

FGR: fetal growth restriction

FHR: fetal heart rate

FHT: fetal heart tone or fetal heart tracing

FL: femur length

FLM: fetal lung maturity

FM: fetal movement

FSE: fetal scalp electrode

G: gravida

g or gm: gram

GA: gestational age

GBS: group B Streptococcus

GC: gonorrhea

GDM: gestational diabetes mellitus

GI: gastrointestinal

GTD: gestational trophoblastic disease

GTT: glucose tolerance test

GYN: gynecology

h or hr: hour

HC: head circumference

HELLP: hemolytic anemia, elevated liver enzymes, and low platelets

Hb or Hgb: hemoglobin

H/H: hemoglobin and hematocrit

H&P: history and physical examination

HPV: human papillomavirus

HRT: hormone replacement therapy

HSIL: high-grade squamous intraepithelial lesion

HSG: hysterosalpingogram

HSV: human simplex virus

HT: hormone therapy

HTN: hypertension

Hx: history

IC: interstitial cystitis

ICSI: intra-cytoplasmic sperm injection

IOL: induction of labor

IM: intramuscular

IUD: intrauterine device

IUFD: intrauterine fetal demise

IUGR: intrauterine growth restriction

IUI: intrauterine insemination

IUP: intrauterine pregnancy

IUPC: intrauterine pressure catheter

IV: intravenous

IVF: in vitro fertilization

KB (S): Kleihauer-Betke stain

Kg: kilogram

L&D: Labor and Delivery

LAVH: laparoscopically assisted vaginal hysterectomy

LBW: low birth weight

LEEP: loop electrode excisional procedure

LGA: large for gestational age

LMP: last menstrual period or low malignant potential tumor

LMWH: low molecular weight heparin

L/S: lecithin/sphingomyelin ratio

LSIL: low-grade squamous intraepithelial lesion

LTCS: low transverse cesarean section

min: minute

m or mo: month

Mg: magnesium sulfate

MI: myocardial infarction

MTX: methotrexate

NEJM: N Eng J Med

NG: nasogastric

NICU: neonatal ICU

NPO: nothing per mouth

NPV: negative predictive value

NS: normal saline

NSAID: non-steroidal anti-inflammatory drug

NST: non-stress test

NSVD: normal spontaneous vaginal delivery

NT: nuchal translucency

NTD: neural tube defects

O2Sat: arterial oxygen saturation

OB: Obstetrics

OBT: OB triage

OC: oral contraceptive

OCP: oral contraceptive pills

OG: Obstet Gynecol

OI: ovulation induction

OR: operation room

P: para

PAP: Papanicolaou smear (cervical cytology)

PAS: Placenta accreta spectrum

PB: ACOG Practice Bulletin

PCOS: polycystic ovarian syndrome

PE: pulmonary embolism or physical exam

PGD: preimplantation genetic diagnosis

PID: pelvic inflammatory disease

PIH: pregnancy induced hypertension

PMDD: premenstrual dysphoric disorder

PMS: premenstrual syndrome

PO or po: by mouth

POC: products of conception

PPD: purified protein derivative of TB

PPH: postpartum hemorrhage

PRBC: packed red blood cell

PROM: premature rupture of membrane

PPROM: preterm premature rupture of membrane

PPV: positive predictive value

PR: per rectum

PRN or prn: as needed

PTL: preterm labor

PUBS: percutaneous umbilical blood sampling

PV: per vagina

q: every

QD or qd: every day or once a day

Q8h or q8h: every 8 hours

RBC: red blood cell

REI: reproductive endocrinology & infertility

ROM: rupture of membrane

Rx: therapy

SAB: spontaneous abortion

sats: saturations

SC: subcutaneous

SD: shoulder dystocia or standard deviation

sec: second

S/P: status post or after

SGA: small for gestational age

SLE: systemic lupus erythematosus

SSRIs: selective serotonin-reuptake inhibitors

SROM: spontaneous rupture of membranes

STD: sexually transmitted disease

STI: sexually transmitted infection

SVD: spontaneous vaginal delivery

Sx: symptoms

TAH: total abdominal hysterectomy

TCA: tricyclic antidepressant

TID or tid: three times daily

TOA: tuboovarian abscess

TOL: trial of labor

TOT: trans-obturator tape

T&S: type and screen

TSH: thyroid-stimulating hormone

TVH: total or trans-vaginal hysterectomy

TVT: trans-vaginal tape

UA: urine analysis

UI: urinary incontinence

UDS: urine drug screen

UPT: urine pregnancy test

UTI: urinary tract infection

US or U/S: ultrasound

VB: vaginal bleeding

VBAC: vaginal birth after cesarean

VD: vaginal delivery

VIN: vulvar intraepithelial neoplasia

VTE: venous thromboembolism

w or wk: week

WBC: white blood cells

y or yr: year

OBSTETRICS

OBSTETRIC TRIAGE

Obstetric Triage Acuity

Overview of Obstetric Triage

Pregnant women ≥20 weeks are usually triaged by the nurse and then evaluated by the provider, eg, nurse-midwife, resident, and attending physician at a hospital-based obstetric triage (OB triage, OBT) before admission or discharge.

OB triage unit as a part of Labor and Delivery (L&D) is usually equipped with fetal monitors and ultrasound.

Common conditions encountered include signs of labor at term, preterm contractions or labor, vaginal leaking of fluid, vaginal bleeding, abdominal pain, signs or symptoms of preeclampsia, decreased fetal movement, and trauma.

Classification Based on Urgency

ACOG recommends that hospitals establish guidelines for triage of pregnant women (CO 667. OG 2016;128:e16).

TheMaternal-Fetal Triage Index developed by the Association of Women’s Health, Obstetric and Neonatal Nurses (AWHONN) could be used as templates (J Obstet Gynecol Neonatal Nurse 2015;44:701).

STAT/Priority 1

Abnormal Vital Signs

Maternal HR <40 or >130, apneic, Sp02 <93%, systolic BP ≥160 or diastolic BP ≥110 or <60/palpable, no FHR detected by Doppler unless previously diagnosed fetal demise, FHR <110 bpm for >60 seconds

Immediate Lifesaving Intervention Required

Maternal: Cardiac compromise, severe respiratory distress, seizure, hemorrhage, acute maternal status change or unresponsive, signs of placental abruption or uterine rupture

Fetal: Prolapsed cord

Immediate birth: Fetal parts visible on the perineum, active maternal pushing

Urgent/Priority 2

Abnormal Vital Signs

Maternal HR >120 or <50, T≥101 ⁰F(38.3 ⁰C), RR>26 or <12, SpO2 <95%, systolic BP≥140 or diastolic BP ≥90 with symptoms or BP <80/40, repeated; FHR>160 bpm for >60 sec; decelerations

High-Risk Situations

Unstable, high risk medical conditions; difficulty breathing; altered mental status, suicidal or homicidal; <34 weeks with uterine contractions; <34 weeks with vaginal leaking or spotting; active vaginal bleeding (not spotting or show); decreased fetal movement; recent trauma

Severe pain unrelated to contractions ≥7/10

≥34 weeks with regular contractions or SROM/leaking with any of the following: HIV positive; planned, medically-indicated cesarean; breech or other malpresentation; multiple gestation; placenta previa

Transfer of Care Needed

Maternal or fetal indications per hospital policy

Prompt/Priority 3

Abnormal Vital Signs

T>100.4 ⁰F(38 ⁰C), SBP≥140 or DBP ≥90 asymptomatic

Conditions Requiring Prompt Attention

Signs of active labor ≥34 weeks; early labor signs or SROM/leaking at 34–36 6/7 weeks; ≥34 weeks with regular contractions and genital HSV lesion; ≥34 weeks planned, elective, repeat cesarean with regular contractions; ≥34 weeks multiple gestations with irregular contractions; women is not coping with labor well.

Non-urgent/Priority 4

≥37 weeks with early labor signs or SROM/leaking

Non-urgent symptoms may include common discomforts of pregnancy, vaginal discharge, constipation, ligament pain, nausea, anxiety

Scheduled or Requesting/Priority 5

Scheduled procedures with no complaints, prescription refill, outpatient service missed

Term Labor Admission

True Labor versus False Labor

Identifying the patient in true labor is important for patient safety.

Women with false labor can be released from OB triage after the fetal well-being is assured and documented.

If unsure about laboring status at initial presentation, observe the patient in OB triage for 1–2 hours. Labor is diagnosed if cervix changes.

True Labor

Regular contractions, ie, every 5 minutes

Intervals gradually shorten.•Intensity gradually increases.

Cervix dilates/effaces.

Discomfort is not stopped by sedation.

False Labor

Irregular contractions with long intervals

Intensity unchanged

Cervix not dilating/effacing

Discomfort, mainly in lower abdomen, relieved by sedation

Admission Criteria for Laboring Patients

Admission criteria vary among institutions.

Diagnosis of labor can be difficult at times. Labor progression is highly unpredictable.

Whether to admit a patient to L&D should be individualized.

General Criteria for Admission

Patients are generally admitted when cervical dilation ≥3 cm with regular and painful contractions. It is also reasonable to admit when cervical dilation reaches ≥4 cm in uncomplicated pregnancies.

Ruptured membranes

Bloody show or 100% of cervical effacement with regular and painful contractions; bloody show means a small amount of blood with mucus discharge before onset of labor.

Early versus Delayed Admission

Early admission is recommended for high-risk pregnancies (eg, prior cesarean, hypertension, or diabetes), patients with risk factors for intrapartum complications, and patients who are remote from hospitals.

Admission in active labor is associated with lower rates of epidural use and labor augmentation.

Admission in early latent phase is associated with more labor interventions.

Patients may be admitted due to pain or fatigue in latent phase based on individual situation.

Preterm Labor or Contractions

Preterm contractions are one of the most common reasons for visits to OB triage. When the cervix is <2 cm dilated and/or <80% effaced, it is a challenging task to diagnose preterm labor (PTL) or determine who needs to be admitted versus who can go home.

Preterm labor: Defined by regular contractions before 37 weeks and associated cervical changes including dilation, effacement, or both.

Initial Evaluation

History

Suspect preterm labor if patient complains of contractions, menstrual-like cramping, pelvic pressure, vaginal spotting, or back pain.

Speculum Examination

Always precedes digital examination. Avoid gel if plan to collect sample for fetal fibronectin (fFN) or insert a swab into the posterior fornix without using a speculum (blind sampling technique for fFN).

Inspect cervix for dilation, lesions, or bleeding.

Dip the swab in posterior fornix for 10 sec to collect sample for fFN.

Collect sample from the lower vagina and rectum or perianal area for GBS culture.

If vaginal infection is suspected, collect specimen for wet mount; if patient has had no prenatal care, test for gonorrhea/chlamydia.

Cervical Examination

Cervical dilation means the size of the opening of INTERNAL os, not external os.

Perform cervical exam gently; do not forcefully insert finger into internal os.

Some multiparous women have cervical dilation in 3rd trimester without other evidence of preterm labor.

If there is vaginal bleeding and placental location is unknown, perform ultrasound (US) to rule out placenta previa before cervical digital exam.

Electronic Fetal Monitoring

Assess fetal heart rate patterns and document frequency of uterine contractions

Ultrasound

Fetal biometrics, amniotic fluid volume measurement, fetal presentation, and location of placenta

Transvaginal US for cervical length (CL)

CL >30 mm — PTL unlikely

CL 20–30 mm plus contractions — PTL more likely

CL <20 mm plus contractions — high risk for PTL

Labs

Urine analysis (UA), urine culture, and urine drug screen (UDS); prenatal labs if no prenatal care

Criteria for Admission

Persistent and painful contractions, ie, ≥6 contractions/hour

Rupture of membranes

Vaginal bleeding

Dilation ≥3 cm and/or effacement ≥80%

If Diagnosis of PTL is Uncertain

Continue electronic fetal monitoring (EFM) and tocometry.

Re-examine the cervix in 1–2 hours, preferably by same examiner.

Tocolytic agent is not indicated in women with preterm contraction without cervical change.

There is no evidence to support IV hydration or sedation.

May need to admit patient with persistent and painful contractions for observation.

Early diagnosis of PTL is difficult; many patients diagnosed with PTL do not deliver prematurely.

CL by vaginal US and fFN are commonly used to enhance the diagnosis of PTL. A positive fFN or a short cervix alone has low positive predictive value (PPV) and should not be used exclusively to guide management (PB 171, OG 2016; 128:e155).

Fetal Fibronectin (fFN)

PPV is <20%; negative predictive value (NPV) 69–92%; negative test is useful in ruling out preterm delivery in next 1–2 weeks, but positive test is not helpful.

Test may not be accurate if specimen is contaminated with blood, semen, or gel.

No need to perform the fFN test if:

Gestation <24 weeks or ≥34 weeks

Membranes ruptured

Cervix dilated >3 cm

Patient had intracervical examination, vaginal ultrasound, or intercourse in the last 24 hours

Combination of CL and fFN

Collect fFN sample before vaginal ultrasound

No fFN testing if CL >30 mm

fFN test if CL between 20 mm and 30 mm

Rupture of Membranes

History

Sudden gush of fluid from vagina or water running down the legs usually indicates rupture of membranes (ROM).

Increased vaginal discharge or slight wetness on the underwear is common in pregnancy. Urinary incontinence also occurs in pregnancy.

ROM is commonly associated with contractions or vaginal spotting due to cervical dilation and effacement.

Speculum Examination

Clear fluid pool in vaginal vault or visualization of fluid running out of cervical os offers direct evidence of ROM.

Look for cervical dilation, cervical lesions, or vaginal bleeding; obtain GBS culture if not done; smear fluid on slide for fern test.

Nitrazine test: pH >6.5 consistent with ROM; blood, semen, and bacterial vaginosis may cause false positive test; not commonly used in the US.

Point-of-Care Tests

Commercial tests for diagnosis of PROM are available, including AmniSure, Actim PROM, and ROM Plus; false positive rate 19-30%; still considered ancillary tests (PB 188, 2018;131:e1).

Digital Examination

Do not perform intracervical digital exam if gestation age <34 weeks in patients with ROM as this decreases latency and increases risk of intra-amniotic infection.

If ≥34 weeks and delivery is planned, cervical exam may be needed to determine cervical status for induction of labor (IOL) or labor augmentation. Generally avoid frequent exams in patients with ROM.

Ultrasound

Check amniotic fluid; oligohydramnios may suggest ROM (not diagnostic).

Perform fetal biometry if no prenatal care; measurements can be difficult if oligohydramnios is present and the estimated fetal weight (EFW) can be erroneous.

Disposition

Admit patient if ROM is confirmed; start labor induction if ≥34 weeks.

Discharge patient if workup is negative, fetal heart tones (FHT) reassuring, and no evidence of PTL; caution patient for PTL and schedule close follow-up.

Vaginal Bleeding

Common Etiology

Labor, placenta previa, placenta abruption, cervical lesions, infections, genital and cervical trauma.

History

Establish gestational age: Vaginal bleeding (VB) in early pregnancy (ie, <20 weeks) is usually evaluated in ER.

Elicit the inciting factors, eg, trauma or intercourse.

Onset, Severity and Associated Symptoms

Previa, abruption, and trauma can result in sudden onset and large amount of VB.

Infection-induced bleeding tends to be chronic and small amount.

If VB is labor-induced, patient may also complain of contractions, back pain, abdominal cramping, or leaking fluid.

Placenta abruption is often associated with abdominal pain and contractions.

Cervix, vagina, and external genitalia are prone to trauma and bleeding during pregnancy due to increased tissue fragility and hyperemia.

Physical Examination

Vital signs

Speculum exam: Inspect cervix thoroughly; confirm bleeding from cervical os, external cervix, or vagina; if no bleeding, perform fFN and wet smear if indicated.

Cervical exam: Perform digital exam if no placenta previa by medical records or US.

Labs

If bleeding is significant, check type and screen (T&S), PT, PTT, fibrinogen, and Kleihauer-Betke (KB) test. Give RhIG if Rh is negative.

Ultrasound

US before vaginal exam if unsure of placental location; abdominal US is adequate in most cases; if uncertain, use endovaginal US or translabial US for placental localization.

Check AFI and fetal presentation; fetal biometry if unsure of gestational age

Fetal Monitoring

Non-reassuring FHT and frequent contractions suggest possible placenta abruption.

Disposition

Admit if placenta previa, placenta abruption, or labor is suspected.

Genital trauma, cervical lesions, and infection can usually be managed as outpatient.

Decreased Fetal Movements

Suspect stillbirth when the patient complains of decreased fetal movement (DFM).

Auscultate FHT with hand-held Doppler first. Perform US if the FHT is not found.

DFM may occur before fetal demise. Patients with DFM often need NST and US evaluation.

Workup in OB Triage

Evaluate risk factors of stillbirth (previous stillbirth, FGR, antepartum bleeding, diabetes, hypertension, AMA, IVF, obesity, smoking, or drug abuse).

Check vitals, fundal height and signs of labor (contractions, cervical dilation, and vaginal bleeding).

Perform NST. If initial NST nonreactive, may use vibroacoustic device.

Perform US to check amniotic fluid.

If both NST and amniotic fluid are normal, risk of stillbirth within 1 week is extremely low. Consider discharge with FM counting instructions.

Admit if having persistent nonreactive NST or nonreassuring fetal testing.

Fetal Movement Counts

Lie on left side with hand on the stomach. Count FMs daily any time for at least 1 hour. Write down the number of FMs.

Call OB triage or L&D if:

No fetal movement in 12 hours

<3 movements in 1 hour or <10 movements in 2 hours of focused counting

Movements are half of what they have been

Count-to-Ten Method

Start counting in AM. Record the time of the day when the 10th movement was felt.

Contact care provider if <10 movements in a 12h-period or if it takes longer each day to reach 10 movements.

Normal Fetal Movements

Pregnant women feel FM between 16 and 24 weeks. FM does not decrease at term. Decreased amniotic fluid may limit FM.

DFM is mostly due to fetal sleep that is often resolved even before triage visit. Sleep-wake cycle is 20–75 min with considerable variation.

Increased FM is associated with FHR accelerations and may be seen with maternal hypoglycemia. Hypoxia reduces or ceases FM.

Start fetal movement counting at 28–32 weeks if medically indicated. Ten distinct FMs in 2 hours are considered reassuring.

Fetal Movement Monitoring

No diagnostic criteria for DFM due to wide variation of normal FM and maternal perception.

Both subjective perception (qualitative) and kick counts (quantitative) can be used to monitor FM.

Maternal concern of DFM is more important than the numbers of FMs.

FM monitoring does not reduce the risk of stillbirth, may increase the risk of induction and cesarean (Lancet 2018;392:1629).

Daily FM assessment is not routinely recommended (PB 145. OG 2014;124:182).

Hypertension

History

Gestational age; chronic versus new-onset hypertension (HTN)

Symptoms: Persistent severe headache, abdominal pain in right upper quadrant or epigastrium, scotomata, visual changes, excessive swelling (especially in hands and face), decreased fetal movement, vaginal bleeding, and contractions

Physical Examination

Measure blood pressure (BP); check edema in lower extremities and deep tendon reflexes.

Perform cervical exam and calculate Bishop score for possible induction of labor.

White Coat Hypertension

Defined as elevated BP primarily in the presence of health care providers. May progress to gestational HTN or preeclampsia in 8–40% of patients.

Ambulatory blood pressure monitoring (ABPM) may be used to confirm the diagnosis (USPSTF recommendation). If ABPM devices not available, home blood pressure measurement (HBPM) devices may be acceptable.

Blood Pressure Measurement

Small cuff overestimates actual BP. Use appropriate cuff sizes based on arm circumferences: arm 22–26 cm/small adult cuff 12x22 cm; arm 27–34 cm/medium adult size cuff 16x30 cm; arm 35–44 cm/large adult cuff 16x36 cm; arm 45–52 cm/adult thigh cuff 16x42 cm.

Give patient at least 10-min rest; no tobacco or caffeine for 30 min prior to taking BP.

Patients should be seated with legs uncrossed and back supported. If recumbent position needs to be used, place patient in left lateral decubitus position and cuff at level of right atrium.

Fetal Monitoring

Fetal heart rate patterns and contractions

Labs

Hematocrit, platelet, creatinine, AST,ALT, LDH, and uric acid

Clean urine sample for urine protein; spot urine protein-to-creatinine ratio correlates with 24h urine protein measurement

Ultrasound

Check amniotic fluid level; perform fetal biometry if no prenatal care.

Assessment and Disposition

Consider diagnosis of preeclampsia if systolic BP ≥140 or diastolic ≥90 and urine protein-to-creatinine ratio ≥0.3. Only use 2+ on urine dipstick as diagnostic threshold if other 2 quantitative methods are not available.

Delivery is often indicated if ≥ 37 weeks. May admit the patient to L&D for observation if <37 weeks.

Consider 24h urine collections for protein analysis.

If workup is negative, consider discharge with precautions and close follow-up.

If uncertain, admit for observation.

Trauma in Pregnancy

Initial Evaluation at Emergency Room

Allow trauma team to complete initial maternal evaluation. Mother is always #1 priority.

History: Gestational age, seat belt use, air bag deployment, abdominal pain, vaginal bleeding, fetal movement, resuscitation efforts, and direct abdominal trauma.

May defer pelvic exam in ER if no vaginal bleeding or contractions.

Use US to assess FHT, presentation, placental location, gestation age, and amniotic fluid level. Do not use US to diagnose placental abruption because of low sensitivity.

Monitor contractions and FHR patterns. FHR can change before other vital signs when patient’s condition worsens.

Reposition large uterus away from the great vessels (ie, left uterine displacement)

Obtain labs: CBC, T&S, PT, PTT, fibrinogen, KB stain, and UDS.

If the fetus has died of trauma, assume a massive placental abruption and coagulopathy; be prepared with massive transfusion.

Admit to L&D if >16–20 weeks based on hospital protocol.

Cesarean Delivery

Emergency cesarean delivery may be performed in the situation of imminent maternal death or stable patient with nonreassuring FHR pattern.

Management of Trauma Patients on Labor and Delivery

Continue to coordinate care with trauma team.

Complete H&P, including pelvic exam.

Complete US biometry and AFI.

Give 300 ug RhIG IM if RhD negative or more if >30 ml of feto-maternal bleeding documented by KB test.

Continue fetal monitoring for at least 4 hours; abruption unlikely if contractions <6 per hour for 4 hours.

Extend monitoring for frequent contractions, nonreassuring FHT, vaginal bleeding, rupture of membranes, or severe trauma.

Cardiac Arrest

Etiology

Hemorrhage, amniotic fluid embolism, acute coronary syndrome, and venous thromboembolism (VTE) are the most common causes of maternal cardiac arrest.

Other etiology includes anesthesia complication, drug toxicity, sepsis, hypertensive stroke, metabolic disorder, and electrolyte disturbance.

Key Steps in Maternal Resuscitation

Initial Step

If no pulse and respirations, cardiac arrest is diagnosed.

Call for help

Activate the emergency response system (maternal code)

Call for code cart

Immediate Following Steps

Perform following steps simultaneously

Immediate chest compressions: Place the heel of one hand over the mid-lower sternum, compression rate 100–120/minute, compression/ventilation ratio 30:2. The patient remains in supine position on a backboard. Compress the chest at least 5 cm (2 inches) but no more than 6 cm (2.5 inches). Allow the chest to recoil completely. Minimize any interruptions.

Displace the large uterus (>20 weeks) to the left to reduce aortocaval compression.

Bag mask ventilation with 100% oxygen. Intubation with small endotracheal tube (6–7 mm).

Prepare for fetal delivery while performing maternal resuscitation.

Defibrillation

Use automated external defibrillator (AED) to assess the cardiac rhythm.

Remove fetal monitor.

When indicated, perform defibrillation ASAP.

Do not perform other interventions (eg, intubation, IV, or administration of medication) before rhythm assessment and defibrillation.

After a single shock, immediately resume chest compressions.

Perimortem Cesarean

Pregnant uterus impedes the efforts of cardiopulmonary resuscitation. Cesarean aids in maternal resuscitation.

Consider perimortem cesarean timely if pregnancy or uterine size is ≥20 weeks.

Timing

When initial resuscitation is unsuccessful, perimortem cesarean should be performed. The shorter time from cardiac arrest to delivery, the better the maternal and neonatal outcomes. Delivery within a 4–5-minute window should be targeted.

Postponing cesarean 4–5 minutes is unnecessary if the time of cardiac arrest is unknown, or spontaneous return of circulation is unlikely.

Even after 4–5-minute window, delivery may still be of benefit. There is no clear threshold for death or damage at 4 minutes.

Cesarean Techniques

One scalpel is enough.

Make midline vertical skin incision from xiphoid to pubic symphysis.

Perform vertical (classical) uterine incision to deliver the fetus.

If indicated, vertical incision can be extended for open-chest cardiac massage.

LABOR AND DELIVERY

Intrapartum Fetal Monitoring

Strong uterine contractions interrupt uteroplacental blood flow and transfer of oxygen from mother to fetus. Almost all the fetuses tolerate transient hypoxemia and hypoxia without sustaining any injuries.

The goal of intrapartum monitoring is to identify fetal hypoxia, timely correct the problem, and promptly intervene in early metabolic acidosis.

Prolonged interruption of oxygenation results in metabolic acidosis, tissue damage, or even death (Figure 2.1).

Overview of Intrapartum Fetal Monitoring

Electronic Fetal Monitoring (EFM)

Electronic monitoring of fetal heart rate (FHR) is intended to determine fetal oxygenation status by monitoring FHR patterns.

Fetal brain modulates the heart rate; net result of fetal hypoxia is decreased variability and fetal bradycardia. In essence, FHR monitoring is fetal brain monitoring.

EFM has poor inter- and intra-observer reliability and a high false-positive rate. Operative vaginal delivery and cesarean rate are increased as a result of wide use of EFM.

EFM is called cardiotocography (CTG) in Europe. It has been widely used in the US since 1970 and become standard of care without going through vigorous RCT.

Alternatives to EFM

Fetal Scalp pH

The technique of intermittent sampling of fetal scalp blood is difficult to perform. The interpretation and application of results can be uncertain.

No differences in cesarean rate and neonatal outcomes.

Fetal Pulse Oximetry

Indirectly measures the oxygen saturation of fetal hemoglobin using an intrauterine sensor in contact with fetal skin.

No consistent reduction of cesarean rates or improvement of neonatal outcomes (NEJM 2006;355:2195).

Fetal ECG ST-segment and T-wave Analysis (STAN)

Myocardial hypoxia can lead to elevation of ST-segment and T wave, but use of STAN during labor as an adjunct to the standard EFM did not improve perinatal outcomes or decrease cesarean delivery rates (NEJM 2015;373:632 and OG 2016;127:127).

Definitions of Fetal Heart Rate Patterns

The National Institute of Child Health and Human Development (NICHD) updated the guidelines on electronic fetal monitoring in 2008. ACOG published two Practice Bulletins (OG 2009;114:192 and OG 2010;116:1232) based on the new NICHD guidelines.

The terms, eg, beat-to-beat variability, short-term variability, and long-term variability are not used.

Baseline

Need a minimum of 2 min in any 10-min segment; the segments do not have to be contiguous; fetal heart rate (FHR) rounded to increments of 5 bpm.

Normal: 110–160 beats per minute (bpm)

Bradycardia: <110 bpm

Tachycardia: >160 bpm

Baseline Variability

Measured from peak to trough and excludes decelerations and accelerations.

Absent: amplitude range undetectable

Minimal: amplitude range ≤5 bpm

Moderate: 6–25 bpm

Marked: >25 bpm

Acceleration

Abrupt increase in FHR

≥32 weeks: ≥15 bpm above baseline, with a duration ≥15 sec (15x15 rule)

<32 weeks: ≥10 bpm above baseline, with a duration ≥10 sec

Prolonged acceleration: lasts ≥2 min and <10 min; defined as baseline change if lasting ≥10 min.

Acceleration can be elicited by scalp stimulation or vibroacoustic stimulation if no spontaneous acceleration is present.

Decelerations

Variable Decelerations

Abrupt decrease in FHR; drop ≥15 bpm, last ≥15 sec and <2 minutes in duration.

When associated with contractions, their onset, depth, and duration vary with contractions (Figure 2.2).

Additional features of variable decelerations, ie, variable with a late component, shoulders, or overshoot, are not clearly defined by NICHD.

Most common deceleration patterns; typically result from cord compression.

Late Decelerations

Symmetrical and gradual decrease and return of FHR.

Gradual decrease is defined as ≥30 sec from the onset to the nadir of deceleration.

Associated with contractions; delayed in timing and nadir occurs after the peak of contractions (Figure 2.3).

Recurrent late decelerations occur with ≥50% of contractions; intermittent late decelerations occur with <50% of contractions in 20-min segment.

Usually due to uteroplacental deficiency.

Early Decelerations

The shape of early decelerations resembles that of late decelerations; gradual decrease in FHR with onset to nadir ≥30 sec.

Deceleration begins with a contraction, and the nadir occurs at the same time as the peak of the contraction (Figure 2.4).

Result from fetal head compression; uncommon pattern; may occur in active labor between 4–7 cm dilation.

No clinical significance and considered benign finding.

Sinusoidal FHR Pattern

Smooth, sine wave-like undulating pattern with a cycle frequency of 3–5/min that persist for ≥20 min (Figure 2.5).

Rare pattern but significant; associated with severe fetal anemia or acidosis; also occurs after certain narcotics, eg, butorphanol or nalbuphine.

Prolonged Decelerations

Last ≥2 min but <10 min in duration.

Uterine Contractions

Counted as number of contractions in 10-min window and averaged over 30 min.

Normal: ≤5 contractions in 10 min

Tachysystole

Defined as >5 contractions in 10 min and averaged over 30 min; also describe presence or absence of associated decelerations.

Hyperstimulation and hypercontractility are no longer used.

Three-Tier Fetal Heart Rate Interpretation System

Category I (Normal)

Includes all of the following (Figure 2.6):

Baseline rate: 110–160 bpm

Baseline FHR variability: Moderate

Late or variable decelerations: Absent

Early decelerations: Present or absent

Acceleration: Present or absent

Category II (Indeterminate)

Includes all FHR tracings not categorized as category I or category III; examples include any of the following:

Baseline Rate

Bradycardia not accompanied by absent baseline variability

Tachycardia

Baseline FHR Variability

Minimal baseline variability

Absent baseline variability not accompanied by recurrent decelerations

Marked baseline variability

Accelerations

Absence of induced accelerations after fetal stimulation

Periodic or Episodic Decelerations

Periodic patterns are those associated with uterine contractions; episodic patterns are those not associated with contractions.

Recurrent variable decelerations accompanied by minimal or moderate baseline variability

Prolonged decelerations ≥2 min but <10 min

Recurrent late decelerations with moderate baseline variability

Variable decelerations with other characteristics, eg, slow return to baseline, overshoots, or shoulders

Category III (Abnormal)

Includes either:

Absent baseline FHR variability and any of the following: recurrent late decelerations, recurrent variable decelerations, or bradycardia

Sinusoidal pattern

Review and Interpretation of FHR Tracings

How Frequent to Review FHR Tracings

For normal laboring patients, FHR tracings should be reviewed every 30 min in the first stage and every 15 min in the second stage.

For high-risk patients, eg, fetal growth restriction and preeclampsia, FHR tracings should be reviewed every 15 min in the first stage and every 5 min in the second stage.

Interpretation of FHR Tracings

All clinically significant decelerations, including variable, late, or prolonged decelerations, interrupt oxygen transfer to the fetus.

The predicative value of grading deceleration based on the depth still requires further investigation (OG 2008;112:661).

Presence of moderate variability reliably predicts absence of fetal metabolic acidemia.

Presence of accelerations (spontaneous or stimulated) reliably predicts absence of fetal metabolic acidemia.

Absence of acceleration does not reliably predict fetal acidemia.

Category III tracings are predictive of abnormal fetal acid-base status and require prompt evaluation and management.

Category II tracings do not reliably predict the presence of fetal hypoxia and metabolic acidemia but require continued surveillance and reevaluation.

How to Describe an Electronic FHR Tracing

Full description includes the following components (CV BAD Change):

Contractions

Variability

Baseline fetal heart rate

Accelerations

Decelerations

Change or trend of FHR pattern over time

General Management of Abnormal FHR Patterns

Ancillary Tests

Digital fetal scalp stimulation and vibroacoustic stimulation are commonly used to elicit FHR accelerations when category II or category III tracings are present.

Most providers do not use fetal scalp pH sampling or Allis clamp scalp stimulation. Fetal pulse oximetry is not clinically useful.

Measures for Intrauterine Resuscitation of Fetus

When low tone is called, administer resuscitation measures systematically (PAP HOT):

Position changes: Reposition the patient to left or right lateral position to relieve cord compression.

Examine the cervix; look for cord prolapse; may perform amniotomy, place fetal scalp electrode, and insert intrauterine pressure catheter (IUPC); consider amnioinfusion for recurrent variable decelerations.

Discontinue Pitocin (oxytocin) to relieve uterine tachysystole.

Hydration: Fluid bolus to correct hypotension; may use ephedrine or phenylephrine for hypotension induced by regional anesthesia.

Oxygen: May be effective by increasing maternal-fetal oxygen gradient to facilitate oxygen transfer.

Tocolysis: Terbutaline 0.25 mg IV or subcutaneously (SC) is an effective measure to abolish contraction-induced decelerations.

Evaluation and Management of Common Abnormal FHR Patterns

Tachysystole

Spontaneous labor: No intervention in category I tracings; may use tocolytics in category II or III tracings.

Induced or augmented labor: May require lower doses of uterotonics in category I tracing; need to stop uterotonics and perhaps give tocolytics in category II or III tracings.

Fetal Tachycardia

Evaluate and treat underlying causes, eg, maternal infections, fever, placenta abruption, medications, and hyperthyroidism.

Fetal Bradycardia

Evaluate for maternal hypothermia, sepsis, and fetal heart abnormality.

Minimal FHR Variability

Common etiology includes fetal sleep, narcotics, magnesium sulfate, and fetal acidemia.

May use fetal scalp or vibroacoustic stimulation to assess fetal condition.

Prolonged Deceleration

Etiology include epidural or spinal anesthesia, prolonged compression on umbilical cord, eclampsia, placenta abruption, or cord prolapse

Immediately perform intrauterine resuscitation measures (PAP HOT algorithm for low tone).

If all measures fail, immediate delivery (eg, operative vaginal delivery or cesarean) is needed.

Variable Deceleration

Intermittent variable decelerations, occurring with <50% of contractions, may not need interventions.

Recurrent variable decelerations (occurring with ≥50% of contractions) with greater depth and longer duration may suggest fetal acidemia in the absence of moderate variability or accelerations.

Amnioinfusion can be used to relieve cord compression due to oligohydramnios; it lowers cesarean rate and improves Apgar scores and cord pH.

Protocol for Amnioinfusion

A bolus infusion of 500 ml of normal saline (NS) x1 or

A bolus infusion of 500 ml of NS followed by a continuous infusion of NS at 1 ml/min.

Recurrent Late Decelerations

Use general resuscitation measures to improve placental perfusion.

If late deceleration persists with presence of minimal variability and absent acceleration, expedited delivery should be considered.

Effects of Medications on FHR Patterns

MgSO4 decreases baseline and variability and inhibits the increase in accelerations especially in preterm gestations.

Morphine decreases the number of accelerations.

Betamethasone decreases variability; can also affect BPP for 24–48 hours.

Butorphanol (Stadol) may cause transient sinusoidal FHR pattern.

Nalbuphine (Nubain) decreases the number of accelerations and variability.

Cocaine increases contractions; no characteristic changes in FHR patterns.

Terbutaline abolishes or decreases the frequency of late and variable decelerations.

β-blockers can reduce fetal heart rate.

Intermittent Auscultation (IA) versus Continuous EFM

IA is to use hand-held Doppler to assess FHR patterns. It detects accelerations and decelerations but cannot accurately determine baseline variability and differentiate between types of decelerations (eg, early, variable, and late decelerations).

IA is equivalent to continuous EFM regarding long-term neonatal outcomes in low risk women. The low risk women are defined as without following conditions: meconium staining, intrapartum bleeding, abnormal or undetermined FHT at admission, congenital anomalies, FGR, prior cesarean, diabetes, hypertensive disease, requirement for oxytocin induction or augmentation. 

IA requires one-on-one nursing, which is impractical and cost-prohibitive in the US hospitals.

For the low-risk patients, IA needs to be performed at least every 30 min in the active phase and every 15 min in second stage.

For the high-risk patients, IA is performed every 15 min in the active phase and every 5 min in the second stage (ACOG/AAP. Guidelines for Perinatal Care 8th ed 2017).

Analgesia and Anesthesia

Many women experience severe pain in labor. Patient’s request is a medical indication for pain relief.

Analgesia and anesthesia do not increase the risk of cesarean birth.

Offer method of pain relief based on patient preference and medical conditions.

Consult anesthesia service in advance if medical or obstetric conditions indicate.

Labor Pain

First stage of labor: Visceral pain from uterine contractions and cervical dilation through T10–L1; usually diffuse lower abdominal pain or lower back pain; may