Maternity/Newborn ATI
Delivery is considered when a biophysical profile score of ________ or lower at any gestational age
4
How much water should a pregnant patient drink daily?
A client who is pregnant should consume 3 L of water each day.
Acrocyanosis
Acrocyanosis is a bluish discoloration of the hands and feet and is an expected finding in a newborn 24 to 48 hr after birth.
Amniocentesis
An amniocentesis is used to determine lung maturity, detect congenital anomalies, and diagnose fetal hemolytic disease.
VEAL chop method for nursing stands for variable deceleration, early deceleration, accelerations, and late decelerations.
And the chop stands for cord compression, head compression, oxygenated or OK, and placental insufficiency.
Betamethasone
Betamethasone is a glucocorticoid that is given to stimulate fetal lung maturity and prevent respiratory distress. It works by promoting the release of enzymes that release lung surfactant.
Caput succedaneum
Caput succedaneum is a benign, edematous area of the scalp and is commonly found on the occiput. Usually resolves on its own in 3-5 days after vacuum-assisted birth.
Manifestations of hyperglycemia
Increased urinary output, nausea and vomiting, reports of thirst, abdominal pain, constipation, drowsiness, and headaches. Other manifestations include weak rapid pulse, fruity breath odor, urine positive for sugar and acetone, and a blood glucose level greater than 200 mg/dL.
Lecithin/sphingomyelin (L/S) ratio
Lecithin/sphingomyelin (L/S) ratio is done as a part of an amniocentesis to evaluate fetal lung maturity.
Maternal Alpha-fetoprotein (AFP)
Maternal Alpha-fetoprotein (AFP) is a laboratory test used to assess for neural tube defects or chromosome disorders.
Nuchal cord
Nuchal cord, or the umbilical cord being wrapped tightly around the neck, can cause bruising and petechiae over the face, head, and neck.
Risk factors for development of preeclampsia
Pregestational diabetes mellitus, preexisting hypertension, renal disease, systemic lupus erythematosus, and rheumatoid arthritis.
Kleihauer-Betke test
The Kleihauer-Betke test is used to determine the amount of fetal blood in the maternal circulation when there is a risk of Rh-isoimmunization.
descent phase of labor
The descent phase of labor is characterized by active pushing with contractions every 1 to 2 min, each lasting for 90 seconds.
latent phase of labor
The latent phase of labor is characterized by cervical dilation of 0 to 3 cm and contractions every 5 to 30 min, each lasting 30 to 45 seconds.
Terbutaline (Brethine)
Uses to relax uterine smooth muscle to inhibit uterine activity. A side effect is hypokalemia.
A nurse is assessing a client who received carboprost for postpartum hemorrhage. Which of the following findings is an adverse effect of this medication? a. Hypertension b. Hypothermia c. Constipation d. Muscle weakness
a. Hypertension Other side effects include fever and diarrhea.
A nurse is performing a physical assessment of a newborn upon admission to the nursery. Which of the following manifestations should the nurse expect? SATA a. Yellow sclera b. Acrocyanosis c. Posterior fontanel larger than the anterior fontanel d. Positive Babinski reflex e. Two umbilical arteries visible
b. Acrocyanosis d. Positive Babinski reflex e. Two umbilical arteries visible
A nurse is assessing a client who is at 38 weeks gestation during a weekly prenatal visit. Which of the following findings should the nurse report to the provider? a. Blood pressure 136/88 mm Hg b. Report of insomnia c. Weight gain of 2.2 kg (4.8 lb) d. Report of Braxton Hicks contractions
c. Weight gain of 2.2 kg (4.8 lb) A weight gain of 2.2 kg (4.8 lb) in a week is above the expected reference range and could indicate complications. Therefore, this finding should be reported to the provider.
Antidote for magnesium sulfate
calcium gluconate
In bladder distention, the bladder is suprapubic, round, bulging, and dull to percussion and fluctuates like a balloon filled with water. In this case, the uterus
is usually displaced to the right, boggy, and
Infants exposed to HIV
should receive all routine vaccinations. Infants who are infected with HIV can receive all inactivated vaccinations.
Dilation
widening of the cervix during labor
When is PKU checked for in a newborn?
24 hrs after birth
Taking in phase
24-48 hours after birth: dependent, passive; focuses on own needs; excited, talkative
Caloric intake for a pregnant person?
A client who is pregnant should increase caloric intake by 340 cal during the second trimester and by 452 cal during the third trimester.
How much folic acid should a pregnant person take daily?
A client who is pregnant should increase folic acid intake to 600 mcg daily. Folic acid assists with preventing neural tube birth defects.
How much protein should a pregnant patient eat per day?
A client who is pregnant should increase protein intake to 71 g each day during the second and third trimesters.
neonatal abstinence syndrome
A newborn experiencing neonatal abstinence syndrome can exhibit respiratory distress including chest retractions, nasal flaring, tachypnea, and irregular respirations. Other sx include tremors, incessant crying, mottling of the skin, frequent yawning and sneezing, excessive sucking, vomiting, and fevers. CNS irritability (exaggerated reflexes)
Biophysical Profile (BPP)
Assessment of five variables in the fetus that help to evaluate fetal risk: breathing movement, body movement, tone, amniotic fluid volume, and fetal heart rate reactivity. A total score of 10 points or eight out of 10 points with normal amniotic fluid volume is regarded as normal. A score of six indicates that there may be problems that require further evaluation or monitoring. If the pregnancy is at or beyond 37 weeks, delivery of the baby may be considered
Pelvis shape
Gynecoid is well-rounded with a wide pubic arch. This is ideal for vaginal birth. Android, anthropoid, or platypelloid pelvic shape might have difficulty with vaginal birth, resulting in the need for a cesarean delivery.
Non-stress test (NST)
Most widely used technique for antepartum evaluation of fetal well being performed during the third trimester. It tracks fetal heart rate patterns expected with fetal movement and can help identify fetal distress.
What is neonatal abstinence syndrome?
Neonatal abstinence syndrome (also called NAS) is a group of conditions caused when a baby withdraws from certain drugs he's exposed to in the womb before birth. NAS is most often caused when a woman takes drugs called opioids during pregnancy.
Oligohydramnios
Oligohydramnios is a decrease in amniotic fluid and is associated with congenital anomalies such as renal agenesis and intrauterine growth restriction.
Conditions that require further fetal assessment using electronic fetal monitoring
Oligohydramnios, hypertension, diabetes, intrauterine growth restriction, renal disease, decreased fetal movement, previous fetal death, post-term pregnancy, systemic lupus erythematosus, and intrahepatic cholestasis.
Signs of gestational hypertension or preeclampsia
Swelling of the face, sacral area, and fingers can indicate gestational hypertension or preeclampsia. Reduction in renal perfusion leads to sodium and water retention. Fluid moves out of the intravascular compartment into the tissues, causing edema.
active phase of labor
The active phase of labor is characterized by a cervical dilatation of 4 to 7 cm and contractions every 3 to 5 min, each lasting 40 to 70 seconds
expected range for the FHR
The expected range for the FHR is 110/min to 160/min. The FHR is higher earlier in gestation with an average of approximately 160/min at 20 weeks of gestation.
bilirubin level for a newborn under 24 hrs old
The expected reference range for a newborn who is less than 24 hr old is 2 to 6 mg/dL.
Nalbuphine (Nubain)
*class*: opioid agonists/analgesics *Indication*: pain, analgesia during labor, sedation before surgery, supplement to balance anesthesia *Action*: alters perception and response to pain, causes CNS depression *Nursing Considerations*: - use caution with head trauma - can cause dizziness, headache, nausea, vomiting, respiratory depression - do not use with MAOIs - assess pain - asses hemodynamic parameters - may elevate pancreatic enzymes - *Narcan (naloxone)* is the antidote
side effects of magnesium sulfate
- Hypotension - Sedation - Confusion - N/V - Bradycardia - Pruritis - Arrhythmias - Decreased deep tendon reflexes - Respiratory depression/paralysis - Drowsiness - Muscle weakness - Complete heart block - When used immediately prior to delivery it can cause fetal hypoxia, asphyxia, arrhythmias and possible fetal intracranial bleeding
Diet during pregnancy
-3 c dairy daily -6-8 oz of grains -2.5-3 c veggies daily -5.5-6.5 oz protein daily
Premature newborns will have
-abundant lanugo -few heel creases -hypotonia and relaxed posture -abundant vernix caseosa
Indication for administering oxytocin to a postpartum patient
-flaccid uterus -excess vaginal bleeding
Women who have a BMI above 30 should limit their weight gain to ________ to ________ pounds during pregnancy.
11 to 20 pounds. Excessive weight and weight gain increase the risk of complications during and after pregnancy.
Recommended weight gain expected in second trimester
12 lbs
Recommended weight gain expected in third trimester
12 lbs
Hemoglobin (newborn) under 24 hrs
14-24 g/dL
plt range
150,000 to 400,000/mm3
Patients with BMI of 18.5 to 25 should gain how much weight during their pregnancy?
23-35 lbs
Recommended weight gain expected in first trimester
4 lbs
Blood glucose level newborn under 24 hrs
40-60 mg/dL
RBC for pregnant person
5 to 6.25 million/mm3
WBC for pregnant person
5,000 to 15,000/mm3
BUN range
6 to 24 mg/dL
A positive contraction stress test indicates that further evaluation of the fetus is necessary.
A biophysical profile will provide further evaluation with a real-time ultrasound.
serum creatinine range
A normal result is 0.7 to 1.3 mg/dL (61.9 to 114.9 µmol/L) for men and 0.6 to 1.1 mg/dL (53 to 97.2 µmol/L) for women.
Nursing intervention for early decelerations?
Early decelerations indicate fetal head compression and do not require intervention. Continue to monitor the patient.
Firm, deviated fundus
Full bladder! Ask pt when last voided. Assist pt to void.
Nursing interventions for variable decelerations?
The nurse should check the client's cervix if variable decelerations in the FHR occur or the client experiences an urge to bear down. Have the patient change position to relieve umbilical cord compression.
Placenta previa
The nurse should identify that a client who has a placenta previa and is actively bleeding is at an increased risk for preterm labor and hemorrhage. The nurse should initiate interventions such as bed rest, pelvic rest, and continuous fetal heart monitoring, which assesses fetal well-being and the presence of contractions. The nurse should obtain IV access and monitor laboratory values. Also, the nurse should implement interventions to prepare for an emergency birth.
transition phase of labor
The nurse should identify that this phase is characterized by a cervical dilatation of 8 to 10 cm and contractions every 2 to 3 min, each lasting 45 to 90 seconds.
Side effects of combined oral contraceptives
The nurse should instruct the client that depression is a common adverse effect of combined oral contraceptives. Other common adverse effects of the medication include amenorrhea, weight gain, headache, nausea, breakthrough bleeding, and breast tenderness.
Leopold Maneuvers (Abdominal Palpation)
a series of four types of abdominal palpitation for determining fetal position
A nurse is assessing a client who had a vaginal birth 12 hr ago. For which of the following manifestations should the nurse intervene? a. Temperature 37.8°C (100° F) b. Fundus to the right of the umbilicus c. Moderate flow of lochia rubra d. Diaphoresis
b. Fundus to the right of the umbilicus When the nurse is palpating the fundus, it should be firm and in the midline of the abdomen. Deviation to the right usually indicates bladder distention which can result in uterine atony and hemorrhage because the uterus cannot contract normally.
A nurse is caring for a client who is at 36 weeks of gestation and has a prescription for an amniocentesis. For which of the following reasons should the nurse prepare the client for an ultrasound? a. To estimate the fetal weight b. To locate a pocket of fluid c. To determine multiparity d. To prescreen for fetal anomalies
b. To locate a pocket of fluid An ultrasound is done to locate a pocket of amniotic fluid and the placenta prior to an amniocentesis. This decreases the risk of injury to the fetus.
A nurse is discussing prenatal care with a primigravida client at her first prenatal visit. Which of the following statements should the nurse make? a. "You should feel your baby moving at 12 weeks." b. "You should expect your blood glucose level to be checked during each visit." c. "You will have to have a group B streptococcus culture at 35 weeks of your pregnancy." d. "You will have an appointment every other week starting at 36 weeks of gestation."
c. "You will have to have a group B streptococcus culture at 35 weeks of your pregnancy." C. The nurse should instruct the client to expect a culture of the vagina and rectum to test for group B strep between 35-37 weeks of pregnancy.You should feel fetal movement between 16-20 weeks.Screening for gestational diabetes will occur between 24-28 weeks.The client should expect weekly scheduled appointments from 36 weeks until birth.
Contraindications to oral contraceptives
cholecystitis, hypertension, migraine headache
Carboprost tromethamine is a medication given to control postpartum bleeding and prevent hemorrhage by causing uterine contractions and vasoconstriction. Adverse effects include
diarrhea, nausea, vomiting, headache, tachycardia, hypertension, fever, and chills.
Manifestations of mastitis
fever, aches, chills, headaches, and erythema. Erythema can be detected by palpating for warmth; in some clients the skin might appear reddened.
Taking hold phase
focuses on maternal role and care of the newborn; eager to learn; may develop blues
expected reference range of hemoglobin for a client who is pregnant
greater than 11 g/dL
hematocrit for pregnant person
greater than 33%
HELLP syndrome
hemolysis, elevated liver enzymes, low platelets. HELLP is a severe form of pre-eclampsia.
A nurse is providing teaching about breast care to a postpartum client who is bottle feeding her newborn. Which of the following instructions should the nurse include? a. Periodically apply ice packs to the breasts. b. Avoid wearing a bra for 72 hr following birth. c. Run warm water over the breasts during the daily shower. d. Express a small amount of breast milk every 4 hr.
a. Periodically apply ice packs to the breasts. Clients who do not breastfeed will experience breast engorgement 72 to 96 hr following birth when the body begins to produce milk. Ice packs and mild analgesics can decrease pain and inflammation.
Ketonuria in pregnancy
indicates that the client's body is breaking down fat and protein stores for energy and cannot provide the fetus with essential nutrients. This is a priority finding.
The nurse should identify that a client who is pregnant and has gonorrhea is at an increased risk for
premature rupture of membranes, chorioamnionitis, preterm birth, neonatal sepsis, and intrauterine growth restriction
Quickening
the first movement of the fetus in the uterus that can be felt by the mother
Lightening
the sensation of the fetus moving from high in the abdomen to low in the birth canal. Lightening describes the engagement of the fetal head into the pelvis. When this occurs, breathing becomes easier, but urination is more freqent
Uterine tone in abruptio placenta
the uterus will be firm and board-like, and the client will complain of pain
Effacement
thinning of the cervix during labor
WBC range
5,000 to 15,000/mm3
Delivery is considered when a biophysical profile score of _____ or lower is obtained at or after 36 weeks of gestation.
6
Fasting blood glucose range
60 to 105 mg/dL
Preeclampsia signs and symptoms
1. Sudden weight gain 2. Face and hands swollen because they are losing protein so fluid will not stay in the vascular space 3. Headache 4. Blurred vision and seeing spots 5. HYPER-Reflexia 6. Clonus -> SEIZURES
Cordocentesis
A cordocentesis is used to identify fetal blood type and RBC when there is a risk of isoimmune hemolytic anemia.
IUPC (intrauterine pressure catheter)
A device placed into the amniotic space during labor in order to measure the strength of uterine contractions.
Progesterone serum level
A progesterone serum level helps to determine if a client is pregnant and if the pregnancy is ectopic.
A nurse is caring for a client who is at 24 weeks of gestation and has a suspected placental abruption. Which of the following laboratory results should the nurse expect the provider to prescribe? a. Kleihauer-Betke test b. Progesterone serum level c. Lecithin/sphingomyelin (L/S) ratio d. Maternal Alpha-fetoprotein (AFP)
ANS: a. Kleihauer-Betke test EXPLANATION: The nurse should expect the provider to prescribe a Kleihauer-Betke test for a client who has suspected placental abruption to determine if fetal blood is in maternal circulation. This test is useful to determine if Rho-(D) immune globulin therapy should be administered to a client who is Rh-negative.
A nurse is assessing four newborns. Which of the following findings should the nurse report to the provider? a. A newborn who is 26 hr old and has erythema toxicum on his face b. A newborn who is 32 hr old and has not passed a meconium stool c. A newborn who is 12 hr old and has pink-tinged urine d. A newborn who is 18 hr old and has an axillary temperature of 37.7° C (99.9° F)
Answer: d. A newborn who is 18 hr old and has an axillary temperature of 37.7° C (99.9° F) An axillary temperature greater than 37.5° C (99.5° F) is above the expected reference range for a newborn and can be an indication of sepsis. Therefore, the nurse should report this finding to the provider. Explanation: Erythema toxicum is a transient rash that can appear anywhere on a newborn's body during the first 24 to 72 hr following birth and can last up to 3 weeks. This finding requires no treatment. A newborn should pass the first meconium stool within the first 24 to 48 hr following birth. Failure to pass a meconium stool can indicate a bowel obstruction or congenital disorder. This finding is within the expected reference range. Pink-tinged urine is an indication of uric acid crystals and is an expected finding for a newborn during the first week following birth.
Potential risk factors for hyperbilirubinemia in the newborn
Blood group incompatibilities, maternal infection, maternal diabetes, and the administration of oxytocin
Nursing interventions for late decelerations?
FIRST: Turn the client onto her left side since late decelerations indicate uteroplacental insufficiency Palpate the fundus for tachysystole if the FHR exhibits late decelerations. Administer O2 at 8-10 lpm via NRB Increase IV fluids to boost circulating fluid volume
Leopold's Maneuvers
Fetal position determined and be done between contraction. The first step the nurse should take when performing Leopold maneuvers is to palpate the client's fundus to identify the fetal part. Second, the nurse should determine the location of the fetal back. Third, the nurse should palpate for the fetal part presenting at the inlet. Finally, the nurse should palpate the cephalic prominence to identify the attitude of the head.
fundal height
Fundal height should be measured in centimeters and is the same as the number of gestational weeks plus or minus 2 weeks from 18 to 32 weeks gestation.
Polyhydraminos expected findings.
Gastrointestinal malformations and neurological disorders in the fetus Fundal height greater than expected for gestational age, increase in weight gain
contraindications to the administration of methylergonovine
Hypertension, preeclampsia, eclampsia, and heart disease
Septic shock in newborn
Hypotension, tachypnea, mottled or gray skin, cool extremities, rapid pulse
Meperidine (Demerol)
Meperidine is used to relieve pain, particularly during childbirth. It is usually given by injection and provides pain relief for up to four hours. Do not use in patients who are expected to deliver within 4 hrs of medication administration. The most common side-effects are feeling dizzy or sleepy, sweating and nausea. This medication crosses the placenta and causes respiratory depression in the newborn, which peaks 2-3 hrs after administration.
Methylergonovine (Methergine)
Methylergonovine is used to prevent and control bleeding from the uterus that can happen after childbirth. It belongs to the class of medicines called ergot alkaloids. This medicine works by acting directly on the smooth muscles of the uterus and prevents bleeding after giving birth.
Normal symptoms during pregnancy
Nausea upon awakening, leg cramps while sleeping, increase in vaginal discharge due to hyperstimulation of the cervix from an increase in hormones
Manifestations of hypoglycemia in the newborn
Newborns who are large for gestational age are at risk for hypoglycemia. S/s of hypoglycemia in a newborn include: respiratory distress, abnormal cry, jitteriness, lethargy, poor feeding, apnea, and seizures.
Vacuum-assisted birth teaching
Providers choose vacuum-assisted birth when a client has a prolonged second stage of labor or when the fetus is in distress. The client must be fully dilated before undergoing a vaginal birth Expect neonatal swelling on the scalp that will generally resolve within 3-4 days. A vacuum-assisted birth increases the risk of jaundice as the bruises caused by the device dissipate.
reactive nonstress test vs nonreactive nonstress test
Reactive: fetal heart rate accelerations associated with fetal movement Nonreactive: no fetal heart rate accelerations with fetal movement
Moro reflex
Reflex in which a newborn strectches out the arms and legs and cries in response to a loud noise or an abrupt change in the environment
Expected clinical findings in a newborn
The expected reference range for a newborn's heart rate is from 110/min to 160/min while awake. A healthy newborn's temperature averages 37° C (98.6° F), with a range of 36.5° to 37.5° C (97.7° to 99.5°) The expected reference range for a newborn's respiratory rate is from 30/min to 60/min. The expected reference range for a newborn's length is from 45 to 55 cm (17.7 to 21.7 in). The expected reference range for a newborn's weight is from 2,500 to 4,000 g (5.5 lb to 8.8 lb).
Fundus after delivery
The fundus should descend about 1-2 cm every 24 hrs. Ex. Between 1-2 days postpartum, the fundus is 1 cm below the umbilicus. 2 days postpartum, the fundus should be 3 cm below umbilicus. However within the first 24 hrs after birth the fundus should be 1 cm above the umbilicus.
Order for bathing newborn
The nurse should demonstrate how to bathe a newborn by using a head to toe, clean to dirty, approach. Therefore, the nurse should first wipe the newborn's eyes from the inner canthus outward using plain water. The nurse should then wash the newborn's neck by lifting the newborn's chin. Next, the nurse should cleanse the skin around the umbilical cord stump followed by washing the newborn's legs and feet. The last step of the bath should be to clean the newborn's diaper area.
Iron recommendations during pregnancy
The recommendation for iron intake during pregnancy is higher than that for women who are not pregnant. For women who are pregnant, it is 27 mg/day. For women who are not pregnant, it is 15 mg/day for women younger than 19 years old and 18 mg/day for women between the ages of 19 and 50 years old.
Transient strabismus
Transient strabismus is a normal variation in the newborn's eyes that can persist until the third or fourth month of age.
Fundal massage
What nursing intervention is performed after expulsion of the placenta to increase uterine tone and decrease bleeding?
A nurse is caring for a client who is to receive oxytocin to augment her labor. Which of the following findings contraindicates the initiation of the oxytocin infusion and should be reported to the provider? a. Late decelerations b. Moderate variability of the FHR c. Cessation of uterine dilation d. Prolonged active phase of labor
a. Late decelerations Late decelerations are indicative of uteroplacental insufficiency. Therefore, this is a contraindication for the administration of oxytocin and should be reported to the provider.
A nurse is caring for a postpartum client 8 hrs after delivery. Which of the following factors would place the patient at risk for uterine atony? sata a. Magnesium sulfate infusion b. Distended bladder c. Oxytocin infusion d. Prolonged labor e. Small for gestational age newborn
a. Magnesium sulfate infusion b. Distended bladder d. Prolonged labor
Cow's milk-based formula is recommended for healthy newborns
because it is similar to human breast milk and are recommended for newborns and infants unless prescribed otherwise by the provider.
A nurse is assessing a newborn who was born at 26 weeks of gestation using the New Ballard scale. Which of the following findings should the nurse expect? a. Minimal arm recoil b. Popliteal angle of 90° c. Creases over the entire foot sole d. Raised areolas with 3 to 4 mm buds
a. Minimal arm recoil The nurse should expect a newborn who was born at 26 weeks of gestation to have decreased muscular tone, or minimal arm recoil.
A nurse is calculating a client's expected date of birth using Nagele's rule. The client tells the nurse that her last menstrual cycle started on November 27th. Which of the following dates is the client's expected date of birth? a. September 3rd b. September 20th c. August 3rd d. August 20th
a. September 3rd When using Nägele's rule to calculate the estimated date of birth for a client, the nurse should subtract 3 months from the first day of the client's last menstrual cycle and then add 7 days. November 27th minus 3 months equals August 27th. August 27th plus 7 days equals September 3rd.
A nurse is caring for a client who has uterine atony and is experiencing postpartum hemorrhage. Which of the following actions is the nurse's priority? a. Check the client's capillary refill. b. Massage the client's fundus. c. Insert an indwelling urinary catheter for the client. d. Prepare the client for a blood transfusion.
b. Massage the client's fundus. Uterine atony and postpartum hemorrhage indicate that this client is at the greatest risk for hypovolemic shock. This can compromise the perfusion to the client's vital organs, which can lead to death. Therefore, the nurse's priority is to massage the client's fundus to minimize blood loss.
A nurse is assessing a client who is 1 day postpartum and has a vaginal hematoma. Which of the following manifestations should the nurse expect? a. Lochia serosa vaginal drainage b. Vaginal pressure c. Intermittent vaginal pain d. Yellow exudate vaginal drainage
b. Vaginal pressure The nurse should expect a client who has a vaginal hematoma to report pressure in the vagina due to the blood that leaked into the tissues.
Risk factors for mastitis
insufficient emptying of the breasts during breastfeeding, stress, illness, poor nutrition, fatigue, wearing underwire bras, abruptly stopping breastfeeding.
Low progesterone levels in a pregnant patient indicates
risk for preterm labor. Progesterone maintains the lining of the uterus, which maintains the pregnancy. It also reduces uterine contractility.
Uterine tone of placenta previa
the uterus will be relaxed, soft, and painless if the bleeding is caused by placenta previa