You are working with Dr. Martin on the Newborn Service. She directs you to obtain a prenatal history of Rose, a 20-year-old who is being admitted to obstetrics from the emergency department.
expandYou jot down what Dr. Martin knows about her:
Patient is in active labor with ruptured membranes.
First pregnancy.
Estimated gestational age {EGA} 38 weeks based on last menstrual period.
Multiple sexual partners.
No prenatal care.
You introduce yourself to Rose as a member of the pediatric team who will help care for her baby, and start by asking questions about her pregnancy:
Hi Rose, in order to take the best care of your baby when he or she arrives, I have to ask you some questions about you and your health during your pregnancy. Is that ok?
“Yeah, that’s fine.”
Did you have any medical conditions or illnesses before you became pregnant?
“I used to get asthma when I was little but I haven’t had any attacks for a few years.”
When did you find out you were pregnant?
“About four months ago, right before I moved here to look for a job.”
Have you been followed by a doctor during your pregnancy?
“I went to a free clinic once before I moved here. I am still trying to figure out how to apply for health insurance so I couldn’t make any appointments.”
How have you been feeling during your pregnancy?
“I’ve been a little more tired but otherwise I’m okay.”
Have you noticed any foot or leg swelling?
“Not really.”
Have you had any headaches?
“No.”
Have you had any changes in vision?
“No, I can see fine.”
Have you had stomach pain?
“Yeah, that started a few hours ago and comes on every few minutes—like right now!”
Did you have any infections during your pregnancy?
“I had one or two colds, but that’s it.”
Have you taken any medications?
“Just Tylenol, I looked it up on the internet and they said it was okay during pregnancy.”
Adverse Effects of Prenatal Substance Use
Tobacco
Maternal tobacco use during pregnancy increases the risk for low birth weight in the fetus.
There are no characteristic facial abnormalities associated with maternal tobacco use during pregnancy.
Alcohol
There is no “safe” amount of alcohol that can be consumed during pregnancy to ensure that fetal alcohol syndrome (FAS) does not occur.
Fetal alcohol syndrome is a distinct pattern of facial abnormalities (microcephaly, smooth philtrum, thin upper lip), growth deficiency, and evidence of central nervous system dysfunction.
Victims of fetal alcohol syndrome may exhibit cognitive disability and learning problems (i.e., difficulties with memory, attention, and judgment) as well as neurobehavioral deficits such as poor motor skills and impaired hand-eye coordination.
Marijuana
Distinctive effects of marijuana have not been identified.
Heroin and other opiate medications
Maternal heroin use is associated with increased risk of fetal growth restriction, placental abruption, fetal death, preterm labor and intrauterine passage of meconium.
All infants born to women who use opioids during pregnancy should be monitored for symptoms of neonatal abstinence syndrome (i.e. uncoordinated sucking reflexes leading to poor feeding, irritability, and high-pitched cry) and treated if indicated.
Cocaine and Other Stimulants
These cause vasoconstriction leading to placental insufficiency and low birth weight, premature delivery, smaller head circumferences and shorter lengths.
In addition, the National Institute on Drug Abuse notes that “exposure to cocaine during fetal development may lead to subtle, yet significant, later deficits in some children, including deficits in some aspects of cognitive performance, information processing, and attention to tasks abilities that are important for success in school.”
You read in the OB team admission note that Rose’s weight gain has been limited when her current weight is compared to her self-reported pre-pregnancy weight. Her fundal height is less than expected, and her fetus is possibly small for dates. In preparation for meeting with Dr. Martin to present Rose’s case information you quickly review factors that affect fetal growth.
TEACHING POINT
Small for Gestational Age
Newborns who are noted to be smaller than expected for their gestational age are considered small for gestational age (SGA).
Although they are not synonymous, this term is often used interchangeably with:
Fetal growth restriction (FGR)
Intrauterine growth retardation and/or
Intrauterine growth restriction (IUGR)
SGA: An infant is diagnosed as being SGA at time of birth. There are varying definitions for SGA, ranging from less than the third percentile to less than the 10th percentile for weight. Depending on the cutoff level used, up to 70% of SGA infants are small simply due to constitutional factors determined by maternal ethnicity, parity, weight, or height.
IUGR: A fetus is noted to be IUGR during the pregnancy. A growth-restricted fetus is one that has not reached its growth potential at a given gestational age due to one or more causative factors.
Etiologies of SGA at Birth
Maternal factors
Both young and advanced maternal age
Maternal prepregnancy short stature and thinness
Poor maternal weight gain during the latter third of pregnancy
Nulliparity
Lack of medial care during pregnancy
Cigarette smoking, cocaine use, other substance use
Lower socioeconomic status (a proxy for limited access to good nutrition, healthcase, and structural biases)
Polyhydramnios
Short interpregnancy interval
Preeclampsia and/or chronic hypertension
Chronic maternal illness, such as:
Chronic kidney disease
Pregestational diabetes mellitus
Systemic lupus erythematosus and antiphospholipid syndrome
Cyanotic heart disease
Chronic pulmonary disease
Severe chronic anemia
Sickle cell disease
Fetal factors
Chromosomal abnormalities (e.g., trisomies) and syndromes
Metabolic disorders
Congenital infections (e.g., “TORCH” infections: toxoplasmosis, rubella, cytomegalovirus, herpes simplex 2, and “others” including HIV, hepatitis B, human parvovirus, syphilis, and zika.
Medications and other exposures
Amphetamines
Antimetabolites (e.g., aminopterin, busulfan, methotrexate)
Bromides
Cocaine
Ethanol
Heroin and other narcotics (e.g., morphine, methadone)
Hydantoin
Isotretinoin
Metal (e.g., mercury, lead)
Phencyclidine
Polychlorinated biphenyls (PCBs)
Propranolol
Steroids
Tobacco (carbon monoxide, nicotine, thiocyanate)
Toluene
Trimethadione
Warfarin
Uterine and placental abnormalities
Avascular villi
Decidual or spiral artery arteritis
Multiple gestation (limited endometrial surface area, vascular anastomoses)
Multiple infarctions
Partial molar pregnancy
Placenta previa and abruption
Single umbilical artery
Umbilical thrombosis
Abnormal umbilical vascular insertions
Syncytial knots
Tumors, including chorioangioma and hemangiomas
Uterine and placental abnormalities
Uterine malformations
You now organize the maternal history:
20-year-old female at estimated 38 weeks’ gestation based on last menstrual period. Membranes ruptured; in active labor. G1P0. No previous prenatal care.
Meds: Tylenol prn. No prescribed medications; no vitamins, supplements, or complementary or alternative medicines.
PMHx: Asthma, last attack several years ago.
SHx: Living with friends. No insurance. Unemployed. Food insecure.
ROS: Four previous partners. No history of sexually transmitted infection (STI). Smokes 1-3 cigarettes daily (started smoking half pack per day at age 15. Cut back in early pregnancy). Drinks beer on weekends. Smokes marijuana occasionally. No ankle swelling. No headache/vision changes. No abdominal pain until today.
PE: BP 115/70 mm Hg; fundal height: 33 cm; fetal heart tones 135 bpm.
Lab results: Urinalysis (UA) negative protein and glucose
You and Dr. Martin observe as the OB team performs a brief fetal ultrasound. No physical abnormalities of the fetus or placenta are detected, but his size is consistent with a 35-week gestation fetus.
Dr. Martin points out that Rose has not had the laboratory studies that are usually included in routine prenatal care. The results of prenatal screening labs may have a significant impact on the care of the newborn baby. The OB team will include these as part of Rose’s admission orders.
TEACHING POINT
Prenatal Lab Screening
Look for the following prenatal screening lab tests in the maternal record:
Maternal blood type, Rh and antibody screen
Rubella IgG
Hepatitis B surface antigen (HBSAg)
HIV antibody
RPR or VDRL
Urinalysis
Urine nucleic acid amplification testing (NAAT) for chlamydia and gonococcus
Urine or vaginal culture for group B streptococcus
Hepatitis C antibody (in women with a history of IV drug use)
Tuberculosis skin test (e.g., Mantoux) or TB blood test (e.g. Quantiferon) (in women with HIV or who live in a household with someone with active TB)
Patient information on routine testing during pregnancy
U.S. Centers for Disease Control and Prevention guidelines
Centers for Disease Control and Prevention website
World Health Organization Global Update on the Health Sector Response to HIV, 2014, Executive Summary, page 3
You ask Dr. Martin whether or not it is too late to check Rose for Group B Streptococcal (GBS) colonization, as she is already in labor. She discusses the basics of GBS infections with you, noting that Rose does not meet the criteria for empiric intrapartumantibiotic treatment (see Deep Dive) if she is considered to be 38 weeks as per Rose’s last menstrual period dates. On the other hand if the gestation is actually only 35 weeks, then GBS prophylaxis is indicated. Dr. Martin will discuss this with the OB team.
TEACHING POINT
Early Onset Group B Streptococcal (GBS) Disease
Neonatal GBS Facts
GBS infection is a major cause of neonatal bacterial sepsis.
The incidence of early onset GBS disease is 0.23/1000 live births.
20-30% of pregnant women have vaginal or rectal colonization of GBS.
Without antibacterial prophylaxis 1-2% of infants born to colonized women develop invasive disease (sepsis, pneumonia and meningitis).
Risk factors for early onset GBS disease include rupture of membranes > 18 hours, prematurity, intrapartum fever and previous delivery of an infant who developed GBS disease.
Newborn Management
The management of babies born to mothers who are colonized with Group B streptococcus depends on a number of factors:
Clinical appearance
Evidence of maternal chorioamnionitis
Receipt of appropriate GBS prophylactic antibiotics by mother during labor
Duration of membrane rupture
Gestational age less than 37 weeks
Any infant who is ill appearing should undergo a full diagnostic evaluation (complete blood count [CBC], blood culture, chest x-ray and lumbar puncture) and receive IV antibiotics.
Well-appearing infants may undergo a limited laboratory evaluation (CBC and blood culture) or simply be closely monitored over the first few days of life.
American Academy of Pediatrics. Red Book: 2018 Report of the Committee on Infectious Diseases, 31st Edition. Kimberlin, Brady, Jackson
DEEP DIVEIntrapartum Antimicrobial Prophylaxis
Current American Academy of Pediatrics (AAP) and American College of Obstetricians and Gynecologists (ACOG) guidelines indicate that intrapartum antimicrobial prophylaxis against Group B streptococcal disease (GBS) should be administered if one of the following is present and the mother is in labor with ruptured membranes:
Previous infant with invasive GBS disease
GBS bacteriuria during any trimester of the current pregnancy
Positive GBS vaginal-rectal screening culture in the 36 0/7-37 6/7th weeks of current pregnancy
Unknown GBS status at the onset of labor (culture not done, incomplete, or results unknown) and any of the following:
Delivery at < 37 weeks' gestation
Amniotic membrane rupture ≥ 18 hours
Intrapartum temperature ≥ 38°C (100.4°F)
Intrapartum nucleic acid amplification testing (NAAT) positive for GBS
Appropriate antibiotics for intrapartum antibiotic prophylaxis include penicillin, amoxicillin, and cefazolin. In the penicillin-allergic mother, clindamycin or vancomycin may be used after determining sensitivity.