High-risk pregnancies

High-risk pregnancies US Medical PG Question 1: You have been entrusted with the task of finding the causes of low birth weight in infants born in the health jurisdiction for which you are responsible. In 2017, there were 1,500 live births and, upon further inspection of the birth certificates, 108 of these children had a low birth weight (i.e. lower than 2,500 g), while 237 had mothers who smoked continuously during pregnancy. Further calculations have shown that the risk of low birth weight in smokers was 14% and in non-smokers, it was 7%, while the relative risk of low birth weight linked to cigarette smoking during pregnancy was 2%. In other words, women who smoked during pregnancy were twice as likely as those who did not smoke to deliver a low-weight infant. Using this data, you are also asked to calculate how much of the excess risk for low birth weight, in percentage terms, can be attributed to smoking. What is the attributable risk percentage for smoking leading to low birth weight?

• A. 40%
• B. 30%
• C. 20%
• D. 10%
• E. 50% (Correct Answer)

High-risk pregnancies Explanation: ***50%*** - This value is calculated using the formula for **attributable risk percent (ARP)** in the exposed group: ARP = ((Risk in exposed - Risk in unexposed) / Risk in exposed) × 100. - Given that the risk of low birth weight in smokers (exposed) is 14% and in non-smokers (unexposed) is 7%, the calculation is ((0.14 - 0.07) / 0.14) × 100 = (0.07 / 0.14) × 100 = **0.50 × 100 = 50%**. *40%* - This percentage does not align with the provided risk values for low birth weight in smokers (14%) and non-smokers (7%). - A calculation of ((0.14 - 0.07) / 0.14) * 100 does not yield 40%. *30%* - This value is incorrect, as it would suggest a smaller difference in risk between the exposed and unexposed groups relative to the risk in the exposed group than what is presented in the problem. - The calculated attributable risk percent is higher than 30%. *20%* - This option is significantly lower than the true attributable risk percent derived from the given risk figures. - It would imply a much weaker association between smoking and low birth weight in terms of excess risk than what is calculated. *10%* - This value is substantially different from the correct calculation and would suggest a very minor attributable risk. - The attributable risk percent for smoking leading to low birth weight is much higher than 10% based on the provided data.

High-risk pregnancies US Medical PG Question 2: A 26-year-old woman, gravida 2, para 1, at 28 weeks' gestation comes to the physician for a prenatal visit. She feels well. Pregnancy and delivery of her first child were uncomplicated. Her temperature is 37.2°C (99°F) and blood pressure is 163/105 mm Hg. Her blood pressure 10 weeks ago was 128/84 mm Hg. At her last visit two weeks ago, her blood pressure was 142/92 mm Hg. Pelvic examination shows a uterus consistent in size with a 28-week gestation. A complete blood count and serum concentrations of electrolytes, creatinine, and hepatic transaminases are within the reference range. A urinalysis is within normal limits. Which of the following is the most appropriate next step in management?

• A. Oral labetalol therapy (Correct Answer)
• B. Lisinopril therapy
• C. Magnesium sulfate therapy
• D. Complete bed rest
• E. Dietary salt restriction

High-risk pregnancies Explanation: **Oral labetalol therapy** - The patient has developed **gestational hypertension** (blood pressure ≥140/90 mmHg on two occasions at least 4 hours apart after 20 weeks gestation, without proteinuria or other signs of preeclampsia), with her current BP of 163/105 mmHg confirming **severe range hypertension** (systolic ≥160 mmHg or diastolic ≥110 mmHg). - **Labetalol** is a first-line agent for managing hypertension in pregnancy due to its established safety profile and efficacy in lowering blood pressure. *Lisinopril therapy* - **Angiotensin-converting enzyme (ACE) inhibitors** like lisinopril are **contraindicated in pregnancy** as they can cause fetal renal dysfunction, oligohydramnios, and neonatal hypotension. - This medication choice would be harmful to the fetus. *Magnesium sulfate therapy* - **Magnesium sulfate** is indicated for the **prevention and treatment of seizures in preeclampsia/eclampsia**, not for blood pressure control itself. - While the patient has hypertension, there are no signs of preeclampsia (e.g., proteinuria, signs of end-organ damage), making magnesium sulfate inappropriate at this stage. *Complete bed rest* - **Complete bed rest** is no longer recommended for the management of gestational hypertension or preeclampsia, as studies have shown it does not improve maternal or fetal outcomes and can increase the risk of **thromboembolism**. - It can also negatively impact a patient's quality of life without providing therapeutic benefit. *Dietary salt restriction* - While generally recommended for hypertension outside of pregnancy, **severe salt restriction** in pregnancy is **not typically recommended** for gestational hypertension or preeclampsia, as it has not been shown to improve outcomes and could potentially worsen maternal fluid balance. - The primary management for severe range gestational hypertension involves antihypertensive medications.

High-risk pregnancies US Medical PG Question 3: A 27-year-old P1G1 who has had minimal prenatal care delivers a newborn female infant. Exam reveals a dusky child who appears to be in distress. Her neck veins are distended and you note an enlarged v wave. She has a holosystolic murmur. Following echocardiogram, immediate surgery is recommended. For which of the following conditions was the mother likely receiving treatment during pregnancy?

• A. Bipolar disorder (Correct Answer)
• B. Hypothyroidism
• C. Depression
• D. Hypertension
• E. Diabetes

High-risk pregnancies Explanation: ***Bipolar disorder*** - The newborn's symptoms, including a **holosystolic murmur**, **distended neck veins** with an **enlarged v wave**, and cyanosis, are highly suggestive of **Ebstein's anomaly**. - **Ebstein's anomaly** is a congenital heart defect strongly associated with maternal **lithium use** during pregnancy, a common treatment for bipolar disorder. *Hypothyroidism* - Maternal hypothyroidism is associated with an increased risk of miscarriage, stillbirth, and neurodevelopmental problems in the child, but not specifically with Ebstein's anomaly. - Treatment for hypothyroidism primarily involves thyroid hormone replacement, which is not linked to this specific cardiac defect. *Depression* - While various antidepressant medications can be taken during pregnancy, none are specifically linked to Ebstein's anomaly. - Maternal depression itself can impact fetal development due to stress, but not typically through this specific congenital heart defect. *Hypertension* - Maternal hypertension is associated with conditions like **pre-eclampsia**, fetal growth restriction, and preterm birth, but not specifically with Ebstein's anomaly. - Antihypertensive medications generally do not cause this specific congenital heart defect. *Diabetes* - Maternal diabetes can lead to **macrosomia**, **hypoglycemia**, and an increased risk of various congenital anomalies, including **ventricular septal defects** and **transposition of the great arteries**. - However, it is not specifically linked to Ebstein's anomaly, which is more characteristic of lithium exposure.

High-risk pregnancies US Medical PG Question 4: A 35-year-old woman, gravida 2, para 1, at 16 weeks' gestation comes to the office for a prenatal visit. She reports increased urinary frequency but otherwise feels well. Pregnancy and delivery of her first child were uncomplicated. Her vital signs are within normal limits. Pelvic examination shows a uterus consistent in size with a 16-week gestation. Urinalysis shows mild glucosuria. Laboratory studies show a non-fasting serum glucose concentration of 110 mg/dL. Which of the following is the most likely explanation for this patient's glucosuria?

• A. Decreased SGLT2 expression
• B. Increased glomerular filtration barrier permeability
• C. Decreased insulin production
• D. Decreased insulin sensitivity
• E. Increased glomerular filtration rate (Correct Answer)

High-risk pregnancies Explanation: ***Increased glomerular filtration rate*** - During pregnancy, the **glomerular filtration rate (GFR)** significantly increases, leading to a higher filtered load of glucose. - This increased load can exceed the reabsorptive capacity of the renal tubules, resulting in **glucosuria** despite normal blood glucose levels. *Decreased SGLT2 expression* - **SGLT2 inhibitors** are medications that decrease glucose reabsorption in the renal tubules, but there is no physiological decrease in SGLT2 expression during normal pregnancy that would cause glucosuria with normal blood glucose. - SGLT2 expression itself is generally not altered in a way that leads to isolated glucosuria in healthy pregnancy. *Increased glomerular filtration barrier permeability* - Increased permeability of the **glomerular filtration barrier** would primarily lead to **proteinuria**, not glucosuria. - Glucosuria implies glucose passing through the barrier normally but being uncleared by the tubules. *Decreased insulin production* - **Decreased insulin production** would lead to **hyperglycemia** in addition to glucosuria, which is not seen here as the non-fasting glucose is 110 mg/dL, well within the normal range. - The patient's blood glucose is normal, ruling out significant insulin deficiency. *Decreased insulin sensitivity* - **Decreased insulin sensitivity** (insulin resistance) is a hallmark of gestational diabetes, but it would primarily cause **hyperglycemia**, which is not present in this patient (non-fasting glucose 110 mg/dL). - While some insulin resistance occurs in pregnancy, it wouldn't cause glucosuria with normal blood glucose in the absence of other factors.

High-risk pregnancies US Medical PG Question 5: A 35-year-old G1 is brought to the emergency department because of sharp pains in her abdomen. She is at 30 weeks gestation based on ultrasound. She complains of feeling a little uneasy during the last 3 weeks of her pregnancy. She mentions that her abdomen has not been enlarging as expected and her baby is not moving as much as during the earlier part of the pregnancy. If anything, she noticed her abdomen has decreased in size. While she is giving her history, the emergency medicine physician notices that she is restless and is sweating profusely. An ultrasound is performed and her blood is sent for type and match. The blood pressure is 90/60 mm Hg, the pulse is 120/min, and the respiratory rate is 18/min. The fetal ultrasound is significant for no fetal heart motion or fetal movement. Her blood work shows the following: hemoglobin, 10.3 g/dL; platelet count, 1.1*10(5)/ml; bleeding time, 10 minutes; PT, 25 seconds; and PTT, 45 seconds. Which of the following would be the best immediate course of management for this patient?

• A. Low-molecular-weight heparin
• B. Fresh frozen plasma
• C. Initiation of labor
• D. D-dimer assay
• E. IV fluids (Correct Answer)

High-risk pregnancies Explanation: ***IV fluids*** - The patient presents with **hypotension** (90/60 mmHg) and **tachycardia** (120/min), indicating **hypovolemic shock**, likely due to concealed hemorrhage from abruptio placentae. - **IV fluids** are the immediate priority to restore circulating blood volume and stabilize the patient's hemodynamic status. *Low-molecular-weight heparin* - This patient is experiencing signs of **disseminated intravascular coagulation (DIC)**, including thrombocytopenia, prolonged PT/PTT, and increased bleeding time, which makes anticoagulation contraindicated. - Administering heparin would **exacerbate bleeding** and worsen her condition. *Fresh frozen plasma* - While **fresh frozen plasma (FFP)** can replace clotting factors and is indicated for DIC, stabilization of the patient's circulating volume with **IV fluids** is the most immediate life-saving measure in active shock. - FFP should be given after initial fluid resuscitation and once the decision to deliver is made, to correct coagulopathy. *Initiation of labor* - Although the immediate delivery of the fetus is necessary to resolve ongoing placental abruption and DIC, the patient's **hemodynamic instability** must be addressed first. - Stabilizing her with **IV fluids** is crucial before proceeding with labor induction or C-section. *D-dimer assay* - A **D-dimer assay** is a diagnostic test that would likely be elevated in this patient due to DIC, but it does not provide immediate therapeutic benefit. - The patient's clinical presentation and other lab values (prolonged PT/PTT, thrombocytopenia) already strongly suggest DIC, and immediate intervention is required, not further diagnostic testing.

High-risk pregnancies Flashcard 1 of 5

Question: Poor maternal glucose control leads to excessive transplacental _____ transfer to the fetus

Answer: glucose

High-risk pregnancies Flashcard 2 of 5

Question: Women who are in the _____ period are at particularly high risk of developing myasthenia gravis

Answer: postpartum

High-risk pregnancies Flashcard 3 of 5

Question: Preeclampsia is caused by abnormal placental _____ arteries, causing endothelial dysfunction, vasoconstriction, and ischemia

Answer: spiral

High-risk pregnancies Flashcard 4 of 5

Question: Preeclampsia typically presents _____ the 20th week of gestation

Answer: after

High-risk pregnancies Flashcard 5 of 5

Question: _____ is a blood pressure >140/90 mmHg after the 20th week of gestation with no proteinuria, pre-existing hypertension, nor end-organ damage

Answer: Gestational hypertension