Ans. is C. i.e. Transient tachypnea of the newborn
• The clinical case given above indicates the likely diagnosis of transient tachypnea of the newborn, which is otherwise called Respiratory distress syndrome type II.
• It is characterized by the early onset of dyspnea with chest retractions, expiratory grunting, and cyanosis. Neonates usually recover within 3 days.
• The syndrome is believed to be secondary to slow absorption of fetal lung fluid resulting in decreased pulmonary compliance and tidal volume.
• The distinctive feature of transient tachypnea of the newborn from hyaline membrane disease is the sudden recovery of the infants and the absence of a radiographic reticulo granular pattern on CXR.

Ans. is C. i.e. Dexamethasone 

• Dexamethasone is a corticosteroid & not a Tocolytic agent.
• Steroids are given in preterm labor for fetal lung maturity and not as a tocolytic agent to prevent preterm labor.

Drugs used as TOCOLYTICS

• P: Prostaglandin synthetase inhibitor: Indomethacin
• C: Calcium channel blocker: Nifedipine
• O: Oxytocin antagonist: Atosiban
• S: Magnesium Sulfate
• NO: Nitric Oxide donor: Glyceryl trinitrate
• Bleeding: Beta agonist viz Ritodrine, Terbutaline, isoxsuprine, Salbutamol

Ans. is B. Atosiban 

• Most tocolytics are contraindicated in women with cardiac disease because of their potential to precipitate cardiac failure.
• As there are no studies performed to look at the safety of tocolytic drugs in the setting of existing heart failure the recommendations for their use can be best made based on their side effect profile in normal women.
• Atosiban, an oxytocin antagonist seems to be the drug of choice at present”
• In an animal study, it was shown to have no central hemodynamic effect although some concern has been expressed over the increased infant mortality rate.
• Indomethacin has minimal effect on heart rate and mean arterial pressure and may be used as an alternative for short term tocolysis.
• None of the other tocolytics are considered safe for cardiac disease.
• Beta mimetics probably are the worst. They are contraindicated in Cardiac arrhythmias, Valvular disease, Cardiac ischemia.
• Nifedipine is contraindicated in Conduction defects, Left ventricular failure.
• Magnesium sulfate: Status of magnesium sulfate as regards its safety in cardiac disease is uncertain.

Ans. is B. i.e. Ritodrine
Drugs used as TOCOLYTICS

• P: Prostaglandin synthetase inhibitor: Indomethacin
• C: Calcium channel blocker: Nifedipine
• O: Oxytocin antagonist: Atosiban
• S: Magnesium Sulfate
• NO: Nitric Oxide donor: Glyceryl trinitrate
• Bleeding: Beta agonist viz Ritodrine, Terbutaline, isoxsuprine, Salbutamol

Ans. is C. i.e. Dinoprostone

• The inhibition of uterine contractions, or tocolysis, has been the mainstay therapy for pre-term labor. 
• Specific tocolytic agents are adrenergic receptor agonists Terbutaline, Ritodrine, MgSO4, Ca2+ channel blockers (Nifedipine), COX inhibitors, oxytocin-receptor antagonists, and nitric oxide donors.
• Two forms of prostaglandins are commonly used for cervical ripening before induction at term Misoprostol (PGE1) and Dinoprostone (PGE2)

Ans. is B. i.e. Atosiban 
Atosiban is a selective oxytocin vasopressin receptor antagonist capable of inhibiting oxytocin-induced myometrial contractions.
The mechanism appears to be competitive inhibition of oxytocin receptors in the myometrium and decidua.
Oxytocin antagonists result in a decrease in intracellular free calcium that results in decreased myometrial contractility.

Ans. is D. i.e. Chorioamnionitis

• The patient in the clinical scenario is in preterm labor.
• For patients in 32 weeks of gestation, steroids are given to induce lung maturity.
• But if the patient is having chorioamnionitis, steroids are contraindicated, as steroids can accelerate the infection.
• Chorioamnionitis can be diagnosed clinically by the presence of maternal fever, tachycardia, and uterine tenderness.
• When this is diagnosed, fetal and maternal morbidities increase and delivery is indicated, regardless of the fetal gestational age.
• Ampicillin is the drug of choice to treat group B streptococcal infection.

Ans. is A. i.e. 2.5
On TVS examination of preterm labor patient following findings can be noted.

• Length of cervix < 2.5 cm (2.5 cm is the cut off the length of the cervix to predict PTL)
• Dilatation of cervix > 2 cm
• The shape of cervix appears ‘u’ shaped
• The shape of the cervix on USG: There is bulging of fetal membranes into a widened internal os in case of preterm labor. 
• The normal shape of the cervix is T shape and it changes to Y shape –> V shape and finally to U shape.

Ans. is D. i.e. Respiratory Distress Syndrome

• Most important risk of PTL is, that lungs of the fetus are not mature and hence it can lead to respiratory distress syndrome
• Drug to enhance fetal lung maturity is corticosteroids.
• Antenatal maternal steroid injection at < 32weeks gestation is associated with a 60% reduction in the risk of respiratory distress syndrome.
• Two doses of betamethasone (12mg) are given intramuscularly 24 hours apart, or 4 doses of 6 mg of dexamethasone are given intramuscularly 12 hours apart, to enhance lung maturation.
• Steroids act on type II pneumocyte and stimulate surfactant synthesis.

Ans. is C. i.e. U

• On ultrasound examination, the normal cervix is T shaped.
• As the internal cervical os opens and the membrane starts herniating to the upper part of the endocervical canal, the cervical shape on ultrasound changes to a Y.
• With further progression of cervical changes, Y shape changes to V and ultimately to U.
• Thus, U shaped cervix on transvaginal sonography indicate imminent preterm labor.

Ans. is D. i.e. Progesterone

• The administration of progesterone inhibits the secretion of pro-inflammatory cytokines and delays cervical ripening.
• Thus, progesterone and its derivatives have long been advocated to diminish the onset of preterm labor in women at increased risk due to previous preterm delivery.
• Specific tocolytic agents include beta-adrenergic receptor agonists, MgSO4, Ca2+ channel blockers, COX inhibitors, oxytocin-receptor antagonists, and nitric oxide donors.
• Among the given options progesterone is the drug with the least side effect.

• The lecithin/sphingomyelin (L/S) ratio for assessment of fetal pulmonary maturity.
• The test depends on the outward flow of pulmonary secretions from the lungs into the amniotic fluid, thereby changing the phospholipid composition of the latter and permitting measurement of the L/S ratio in a sample of amniotic fluid.
• In the absence of complications, the ratio of these 2 components reaches 2.0 at approximately 35 weeks.
• The presence of blood or meconium may interfere with test interpretation.

• Ritodrine, salbutamol and magnesium sulfate are tocolytic drugs used to terminate preterm labor and delivery.
• Other tocolytic drugs are isoxsuprine, indomethacin, calcium channel blockers, glyceryl trinitrate, atosiban, and glyceryl trinitrate.

Ans. is A. i.e. Ritodrine

• The infusion of beta-agonists (Ritodrine) has resulted in frequent and at times, serious and fatal side effects.
• Pulmonary edema is a special concern. Because beta-agonists cause retention of sodium and water, with time usually 24 to 48 hours, these can cause volume overload.

The cause of pulmonary edema is multifactorial, and risk factors include:

• Tocolytic therapy with beta-agonists
• Multifetal gestation
• Concurrent corticosteroid therapy
• Tocolysis for more than 24 hours
• Large intravenous crystalloid volume infusion

Ans. is B. i.e. Bed rest, Nifedipine and Dexamethasone
The given situation is a case of preterm labor.
Management of Preterm Labor at < 34 Weeks

• Corticosteroids (Betamethasone/Dexamethasone)

                             +

• Short term tocolytic (Best-nifedipine)

                              +

• MgSo4 (for neuroprotection in pregnancy)

Ans. is C. i.e. 2.5 cm
On TVS examination :

• Length of cervix < 2.5 cm (2.5 cm is the cut off the length of the cervix to predict PTL)
• Dilatation of cervix > 2 cm
• The shape of cervix appears ‘u’ shaped
• The shape of the cervix on USG: There is bulging of fetal membranes into a widened internal os in case of preterm labor. The normal shape of the cervix is T shape and it changes to Y shape → V shape and finally to U shape.

Ans. is D. i.e. All

• Diazoxide is a vasodilator and can be used as a short term tocolytic to control uterine contractions.
• Methyl dopa is also an antihypertensive drug that is used in preterm to reduce uterine contractility.
• MgSO4  inhibits uterine contractility at serum levels of 8-10 meq/l.
• MgSO4 is used by some hospitals in the case of preterm labor to prevent cerebral palsy in the fetus born between 24-27, 6/7 weeks.
• A loading dose of 4-6 gm is given over 20-30 minutes followed by infusion of 1-2 gm/hour.

Ans. is a and b i.e. MgSO4 & dexamethasone

• MgSO4 is used by some hospitals in the case of preterm labor to prevent cerebral palsy in the fetus born between 24-27, 6/7 weeks.
• Corticosteroids cause a significant reduction (40 to 60%) in rates of neonatal death, respiratory distress syndrome and intraventricular hemorrhage and necrotizing enterocolitis. They are safe for the mother.
• Two doses of betamethasone (12mg) are given intramuscularly 24 hours apart, or 4 doses of 6 mg of dexamethasone are given intramuscularly 12 hours apart, to enhance lung maturation.
• There is some concern that Betamethasone available in India has only one component of Betamethasone that is betamethasone sodium phosphate and does not have Betamethasone sodium acetate, which may not be very effective. Hence currently dexamethasone is becoming a drug of choice in India and is economical also.

Drugs used as TOCOLYTICS

• P: Prostaglandin synthetase inhibitor: Indomethacin
• C: Calcium channel blocker: Nifedipine
• O: Oxytocin antagonist: Atosiban
• S: Magnesium Sulfate
• NO: Nitric Oxide donor: Glyceryl trinitrate
• Bleeding: Beta agonist viz Ritodrine, Terbutaline, isoxsuprine, Salbutamol

Ans. is D i.e. Fever
Since the best effect of corticosteroid occurs after 24- 48 hours of administration, at least for this time uterine activity should be stopped, hence short term tocolytic therapy should be given.
Drugs used as TOCOLYTICS

• P: Prostaglandin synthetase inhibitor: Indomethacin
• C: Calcium channel blocker: Nifedipine
• O: Oxytocin antagonist: Atosiban
• S: Magnesium Sulfate
• NO: Nitric Oxide donor: Glyceral trinitrate
• Bleeding: Beta agonist viz Ritodrine, Terbutaline, isoxsuprine, Salbutamol

Beta-Adrenergic receptor-agonists (Terbutaline)

• Side effects: Tachycardia, hypotension, palpitations, shortness of breath, chest pain, pulmonary edema, hypokalemia, hyperglycemia. Contraindications include tachycardia-sensitive maternal cardiac conditions.

Magnesium Sulfate

• Side effects: Hypotension, can potentiate the action of depolarizing and non-depolarizing muscle relaxants, pulmonary edema, nausea, flushing, headache, lethargy. Myasthenia Gravis is a contraindication to the use of magnesium sulfate.

Nitric Oxide Donors (nitroglycerin)

• Side effects: Flushing, tachycardia, hypotension, and headache. There are no real contraindications, but preload dependent cardiac lesions will likely worsen with nitroglycerin.

Calcium Channel Blockers (Nifedipine)

• Side effects: Dizziness, flushing, hypotension. When used with magnesium sulfate: suppression of heart rate, decreased contractility, the elevation of hepatic enzyme levels.

Cyclooxygenase Inhibitors (Indomethacin)

• Side Effects: Nausea, GERD, gastritis, platelet dysfunction.

Oxytocin-receptor antagonists

• Side Effects: Hypersensitivity reactions, injection-site reactions. Atosiban was shown to increase the rate of fetal or infant death in a randomized, double-blinded study.

Ans. is D. i.e. All
Since the best effect of corticosteroid occurs after 24- 48 hours of administration, at least for this time uterine activity should be stopped, hence short term tocolytic therapy should be given.
Drugs used as TOCOLYTICS

• P: Prostaglandin synthetase inhibitor: Indomethacin
• C: Calcium channel blocker: Nifedipine
• O: Oxytocin antagonist: Atosiban
• S: Magnesium Sulfate
• NO: Nitric Oxide donor: Glyceryl trinitrate
• Bleeding: Beta agonist viz Ritodrine, Terbutaline, isoxsuprine, Salbutamol
• Tocolytic of choice: Nifedipine
• Tocolytic of choice in heart disease patient – Atosiban
• Tocolytic with maximum maternal side effects – β agonist
• Side effects of P agonist – M/C = Tremors

• Hyperglycemia
• Hypokalemia
• Pulmonary edema
• Tocolytic with maximum fetal side effects: Indomethacin (like premature closure of ductus arteriosus, oligohydramnios, neonatal pulmonary hypertension)

Beta-Adrenergic receptor-agonists (Terbutaline)

• Side effects: Tachycardia, hypotension, palpitations, shortness of breath, chest pain, pulmonary edema, hypokalemia, hyperglycemia. Contraindications include tachycardia-sensitive maternal cardiac conditions.

Magnesium Sulfate

• Side effects: Hypotension, can potentiate the action of depolarizing and non-depolarizing muscle relaxants, pulmonary edema, nausea, flushing, headache, lethargy. Myasthenia Gravis is a contraindication to the use of magnesium sulfate.

Nitric Oxide Donors (nitroglycerin)

• Side effects: Flushing, tachycardia, hypotension, and headache. There are no real contraindications, but preload dependent cardiac lesions will likely worsen with nitroglycerin.

Calcium Channel Blockers (Nifedipine)

• Side effects: Dizziness, flushing, hypotension. When used with magnesium sulfate: suppression of heart rate, decreased contractility, the elevation of hepatic enzyme levels.

Cyclooxygenase Inhibitors (Indomethacin)

• Side Effects: Nausea, GERD, gastritis, platelet dysfunction.

Oxytocin-receptor antagonists

• Side Effects: Hypersensitivity reactions, injection-site reactions. Atosiban was shown to increase the rate of fetal or infant death in a randomized, double-blinded study.

Ans. is A. i.e. Ritodrine                                  

• Pulmonary edema is a serious complication of beta-adrenergic therapy (ritodrine) and MgSO4.
• This complication occurs in patients receiving oral or (more common) intravenous treatment.
• It occurs more frequently in patients who have excessive plasma volume expansion, such as those with twins or those who have received generous amounts of intravenous fluids and in patients with chorioamnionitis.
• The patient presents with respiratory distress, bilateral rales on auscultation of the lungs, pink frothy sputum, and a typical X-ray picture.
• Patients receiving IV beta-adrenergic drugs should be monitored continuously with a pulse oximeter to anticipate the development of pulmonary edema.

Ans. is A. i.e. Absence of fetal fibronectin at < 37 weeks

• The absence of fetal fibronectin at < 37 weeks is not a risk factor for preterm labor.
• Fibronectin assay: The presence of fibronectin glycoprotein produced by fetal amnion in the cervicovaginal discharge between 24 and 34 weeks is a predictor of preterm labor. 
• When the test is negative it reassures that delivery will not occur within the next 7 days.
• Test = ELISA done between=24-34weeks of pregnancy
• Value > 50 ng/ml are positive for PTL.
• Alkaline phosphatase if > 90 percentile, is also considered as a predictor of PTL.

Risk Factors and Causes Of Preterm Labor (PTL)
Most important risk factor for preterm labor (PTL) is the previous H/O PTL:

• If previous PTL occurred at > 35 weeks: Chances of recurrence are 5%.
• If previous PTL occurred at < 34 weeks: Chances of recurrence are 15%.
• If there is H/O previous 2 PTL at

2. M/C cause of preterm labor is idiopathic followed by infection.
3. Infections which can lead to PTL are:

• Bacterial vaginosis
• Gardnerella vaginalis
• Ureaplasma urealyticum
• Mycoplasma hominis
• Fusobacterium

Other causes are:

• Low socioeconomic status
• Smoking
• Obesity
• Diabetes
• Congenital anomalies of the uterus
• Incompetent OS
• Overstretching of the uterus like in twins, polyhydramnios.

Ans. is D. i.e. Bacterial vaginosis
Hazards of Bacterial Vaginosis
Women with BV are at increased risk for:

• PID
• Postabortal PID
• Postoperative cuff infections after hysterectomy
• Abnormal cervical cytology.

Pregnant women with BV are at risk for:

• PROM
• Preterm delivery
• Chorioamnionitis
• Post cesarean endometritis

Ans. is A. i.e. When given between 28 and 34 weeks
Corticosteroid

• Decreases chances of respiratory distress syndrome.
• Decreases chances of intraventricular hemorrhage.
• Decreases chances of Necrotising enterocolitis
• Corticosteroid can lead to neonatal hypoglycemia (more with betamethasone) and development delay. This is more in fetuses > 34 weeks. So although ACOG recommended the use of corticosteroids beyond 34 weeks, it has not been universally adopted.

Administration of Corticosteroids

• Corticosteroids cause a significant reduction (40 to 60%) in rates of neonatal death, respiratory distress syndrome and intraventricular hemorrhage and necrotizing enterocolitis. They are safe for the mother.
• Two doses of betamethasone (12mg) are given intramuscularly 24 hours apart, or 4 doses of 6 mg of dexamethasone are given intramuscularly 12 hours apart, to enhance lung maturation.
• ACOG-August 2017 guidelines for use of corticosteroid
•  In pregnancy of < 24 weeks: corticosteroid is not recommended
• In pregnancy between 24 weeks to 33 weeks, +6 days corticosteroids should be given to all patients of preterm labor including those with ruptured membranes and twin pregnancy.

Ans. is C. i.e. They provide time for antenatal steroids
Since the best effect of corticosteroid occurs after 24- 48 hours of administration, at least for this time uterine activity should be stopped, hence short term tocolytic therapy should be given.

• ACOG 2016 has concluded that tocolytic agents do not markedly prolong gestation but may delay delivery in some women till 48 hours.
• Tocolytic drugs do not cause a clear reduction in perinatal or neonatal mortality or neonatal morbidity.
• Tocolysis may be considered for women with suspected preterm labor before 34 weeks.
• Tocolysis is contraindicated if prolonging the pregnancy carries a risk to the mother or the fetus.

Ans. is B. i.e. Preterm labor
Levels of fibronectin protein.

• Fibronectin assay: The presence of fibronectin glycoprotein produced by fetal amnion in the cervicovaginal discharge between 24 and 34 weeks is a predictor of preterm labor. When the test is negative it reassures that delivery will not occur within the next 7 days.
• Test = ELISA done between=24-34weeks of pregnancy
• Value > 50 ng/ml are positive for PTL.
• Alkaline phosphatase if > 90 percentile, is also considered as a predictor of PTL.

Ans. is C. i.e. Misoprostol
Drugs used as TOCOLYTICS

• P: Prostaglandin synthetase inhibitor: Indomethacin
• C: Calcium channel blocker: Nifedipine
• O: Oxytocin antagonist: Atosiban
• S: Magnesium Sulfate
• NO: Nitric Oxide donor: Glyceral trinitrate
• Bleeding: Beta agonist viz Ritodrine, Terbutaline, isoxsuprine, Salbutamol

Ans. is B. i.e. Ritodrine
Drugs used as TOCOLYTICS

• P: Prostaglandin synthetase inhibitor: Indomethacin
• C: Calcium channel blocker: Nifedipine
• O: Oxytocin antagonist: Atosiban
• S: Magnesium Sulfate
• NO: Nitric Oxide donor: Glyceral trinitrate
• Bleeding: Beta agonist viz Ritodrine, Terbutaline, isoxsuprine, Salbutamol

Ans. is A. i.e. Repeat dose if the women remain undelivered after the first course

Corticosteroid can lower the risk of:

• Respiratory Distress Syndrome after birth.
• Bleeding within the brain called Intraventricular Hemorrhage.
• Other problems that may cause harm to babies that are born too soon such as intestinal infections called Necrotizing Enterocolitis.

They are indicated in all women with preterm labor between 24 and 34 weeks of gestation.

They should be avoided in clinical chorioamnionitis and eclampsia.

One should avoid multiple courses of antenatal steroids if the women remain undelivered after the first course.

Ans. is D. i.e. Helps fetal lung maturity

Ans. is A. i.e. MgSO4
Antenatal magnesium sulfate for both tocolysis and fetal neuroprotection in premature rupture of the membranes before 32 weeks’ gestation. 
Other tocolytic drugs:

• Ritodrine, salbutamol and magnesium sulfate are tocolytic drugs used to terminate preterm labor and delivery.
• Other tocolytic drugs are isoxsuprine, indomethacin, calcium channel blockers, glyceryl trinitrate, atosiban, and glyceryl trinitrate.

Ans.D. Beta-blocker

• The most important risk of PTL is, that the lungs of the fetus are not mature and hence it can lead to respiratory distress syndrome.
• The drug to enhance fetal lung maturity is corticosteroids.
• Since the best effect of corticosteroid occurs after 24- 48 hours of administration at least for this time uterine activity should be stopped. 
• Hence, short term tocolytic therapy should be given.
• Tocolytic drugs [Note: betamimetic and not beta-blocker is a tocolytic].
• Benzylpenicillin or ampicillin should be given in established preterm labor as prophylaxis against early-onset neonatal sepsis due to Group B Streptococcus in those with known carrier status. 
• In cases of penicillin allergy, clindamycin can be substituted. 
• Ideally, it should be administered 4 hours before delivery.