Chapter 12 Flashcards
- A newly married couple plans to use the natural family planning method of contraception. Understanding how long an ovum can live after ovulation is important to them. The nurse knows that his or her teaching was effective when the couple responds that an ovum is considered fertile for which period of time?
a. 6 to 8 hours
b. 24 hours
c. 2 to 3 days
d. 1 week
ANS: B
Most ova remain fertile for approximately 24 hours after ovulation, much longer than 6 to 8 hours. However, ova do not remain fertile for 2 to 3 days or are viable for 1 week. If unfertilized by a sperm after 24 hours, the ovum degenerates and is reabsorbed.
- What kind of fetal anomalies are most often associated with oligohydramnios?
a. Renal
b. Cardiac
c. Gastrointestinal
d. Neurologic
ANS: A
An amniotic fluid volume of less than 300 ml (oligohydramnios) is often associated with fetal renal anomalies. The amniotic fluid volume has no bearing on the fetal cardiovascular system. Gastrointestinal anomalies are associated with hydramnios or an amniotic fluid volume greater than 2 L. The amniotic fluid volume has no bearing on the fetal neurologic system.
- A pregnant woman at 25 weeks of gestation tells the nurse that she dropped a pan last week and her baby jumped at the noise. Which response by the nurse is most accurate?
a. “That must have been a coincidence; babies can’t respond like that.”
b. “The fetus is demonstrating the aural reflex.”
c. “Babies respond to sound starting at approximately 24 weeks of gestation.”
d. “Let me know if it happens again; we need to report that to your midwife.”
ANS: C
Babies respond to external sound starting at approximately 24 weeks of gestation. Acoustic stimulations can evoke a fetal heart rate response. There is no such thing as an aural reflex. The last statement is inappropriate and may cause undue psychologic alarm to the client.
- At a routine prenatal visit, the nurse explains the development of the fetus to her client. At approximately ____ weeks of gestation, lecithin is forming on the alveolar surfaces, the eyelids open, and the fetus measures approximately 27 cm crown to rump and weighs approximately 1110 g. The client is how many weeks of gestation at today’s visit?
a. 20
b. 24
c. 28
d. 30
ANS: C
These milestones in human development occur at 28 weeks of gestation. These milestones have not occurred by 20 or 24 weeks of gestation but have been reached before 30 weeks of gestation.
- Which statement regarding the structure and function of the placenta is correct?
a. Produces nutrients for fetal nutrition
b. Secretes both estrogen and progesterone
c. Forms a protective, impenetrable barrier to microorganisms such as bacteria and viruses
d. Excretes prolactin and insulin
ANS: B
As one of its early functions, the placenta acts as an endocrine gland, producing four hormones necessary to maintain the pregnancy and to support the embryo or fetus: human chorionic gonadotropin (hCG), human placental lactogen (hPL), estrogen, and progesterone. The placenta does not produce nutrients. It functions as a means of metabolic exchange between the maternal and fetal blood supplies. Many bacteria and viruses can cross the placental membrane.
- A woman in labor passes some thick meconium as her amniotic fluid ruptures. The client asks the nurse where the baby makes the meconium. What is the correct response by the nurse?
a. Fetal intestines
b. Fetal kidneys
c. Amniotic fluid
d. Placenta
ANS: A
As the fetus nears term, fetal waste products accumulate in the intestines as dark green-to-black, tarry meconium. Meconium is not produced by the fetal kidneys nor should it be present in the amniotic fluid, which may be an indication of fetal compromise. The placenta does not produce meconium.
- A woman asks the nurse, “What protects my baby’s umbilical cord from being squashed while the baby’s inside of me?” What is the nurse’s best response?
a. “Your baby’s umbilical cord is surrounded by connective tissue called Wharton’s jelly, which prevents compression of the blood vessels.”
b. “Your baby’s umbilical cord floats around in blood and amniotic fluid.”
c. “You don’t need to be worrying about things like that.”
d. “The umbilical cord is a group of blood vessels that are very well protected by the placenta.”
ANS: A
Explaining the structure and function of the umbilical cord is the most appropriate response. Connective tissue called Wharton’s jelly surrounds the umbilical cord, prevents compression of the blood vessels, and ensures continued nourishment of the embryo or fetus. The umbilical cord does not float around in blood or fluid. Telling the client not to worry negates her need for information and discounts her feelings. The placenta does not protect the umbilical cord.
- Which structure is responsible for oxygen and carbon dioxide transport to and from the maternal bloodstream?
a. Decidua basalis
b. Blastocyst
c. Germ layer
d. Chorionic villi
ANS: D
Chorionic villi are fingerlike projections that develop out of the trophoblast and extend into the blood-filled spaces of the endometrium. The villi obtain oxygen and nutrients from the maternal bloodstream and dispose carbon dioxide and waste products into the maternal blood. The decidua basalis is the portion of the decidua (endometrium) under the blastocyst where the villi attach. The blastocyst is the embryonic development stage after the morula; implantation occurs at this stage. The germ layer is a layer of the blastocyst.
- A woman who is 8 months pregnant asks the nurse, “Does my baby have any antibodies to fight infection?” What is the most appropriate response by the nurse?
a. “Your baby has all the immunoglobulins necessary: immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin A (IgA).”
b. “Your baby won’t receive any antibodies until he is born and you breastfeed him.”
c. “Your baby does not have any antibodies to fight infection.”
d. “Your baby has IgG and IgM.”
ANS: D
During the third trimester, IgG is the only immunoglobulin that crosses the placenta; it provides passive acquired immunity to specific bacterial toxins. However, the fetus produces IgM by the end of the first trimester. IgA immunoglobulins are not produced by the baby. Therefore, by the third trimester, the fetus has both IgG and IgM. Breastfeeding supplies the newborn infant with IgA.
- The measurement of lecithin in relation to sphingomyelin (lecithin/sphingomyelin [L/S] ratio) is used to determine fetal lung maturity. Which ratio reflects fetal maturity of the lungs?
a. 1.4:1
b. 1.8:1
c. 2:1
d. 1:1
ANS: C
The L/S ratio indicates a 2:1 ratio of lecithin to sphingomyelin, which is an indicator of fetal lung maturity and occurs at approximately the middle of the third trimester. L/S ratios of 1.4:1, 1.8:1, and 1:1 each indicate immaturity of the fetal lungs.
- A client arrives for her initial prenatal examination. This is her first child. She asks the nurse, “How does my baby get air inside my uterus?” What is the correct response by the nurse?
a. “The baby’s lungs work in utero to exchange oxygen and carbon dioxide.”
b. “The baby absorbs oxygen from your blood system.”
c. “The placenta provides oxygen to the baby and excretes carbon dioxide into your bloodstream.”
d. “The placenta delivers oxygen-rich blood through the umbilical artery to the baby’s abdomen.”
ANS: C
The placenta delivers oxygen-rich blood through the umbilical vein, not the artery, to the fetus and excretes carbon dioxide into the maternal bloodstream. The fetal lungs do not function as respiratory gas exchange in utero. The baby does not simply absorb oxygen from a woman’s blood system; rather, blood and gas transport occur through the placenta.
- What is the most basic information that a nurse should be able to share with a client who asks about the process of conception?
a. Ova are considered fertile 48 to 72 hours after ovulation.
b. Sperm remain viable in the woman’s reproductive system for an average of 12 to 24 hours.
c. Conception is achieved when a sperm successfully penetrates the membrane surrounding the ovum.
d. Implantation in the endometrium occurs 6 to 10 days after conception.
ANS: D
After implantation, the endometrium is called the decidua. Ova are considered fertile for approximately 24 hours after ovulation. Sperm remain viable in the woman’s reproductive system for an average of 2 to 3 days. Penetration of the ovum by the sperm is called fertilization. Conception occurs when the zygote, the first cell of the new individual, is formed.
- The maternity nurse is cognizant of what important structure and function of the placenta?
a. As the placenta widens, it gradually thins to allow easier passage of air and nutrients.
b. As one of its early functions, the placenta acts as an endocrine gland.
c. The placenta is able to keep out most potentially toxic substances, such as cigarette smoke, to which the mother is exposed.
d. Optimal blood circulation is achieved through the placenta when the woman is lying on her back or standing.
ANS: B
The placenta produces four hormones necessary to maintain the pregnancy: hCG, hPL, estrogen, and progesterone. The placenta widens until 20 weeks of gestation and continues to grow thicker. Toxic substances such as nicotine and carbon monoxide readily cross the placenta into the fetus. Optimal circulation occurs when the woman is lying on her side.
- Which statement regarding the development of the respiratory system is a high priority for the nurse to understand?
a. The respiratory system does not begin developing until after the embryonic stage.
b. The infant’s lungs are considered mature when the L/S ratio is 1:1, at approximately 32 weeks of gestation.
c. Maternal hypertension can reduce maternal-placental blood flow, accelerating lung maturity.
d. Fetal respiratory movements are not visible on ultrasound scans until at least 16 weeks of gestation.
ANS: C
A reduction in placental blood flow stresses the fetus, increases blood levels of corticosteroids, and thus accelerates lung maturity. The development of the respiratory system begins during the embryonic phase and continues into childhood. The infant’s lungs are considered mature when the L/S ratio is 2:1, at approximately 35 weeks of gestation. Lung movements have been visualized on ultrasound scans at 11 weeks of gestation.
- The various systems and organs of the fetus develop at different stages. Which statement is most accurate?
a. Cardiovascular system is the first organ system to function in the developing human.
b. Hematopoiesis originating in the yolk sac begins in the liver at 10 weeks of gestation.
c. Body changes from straight to C-shape occurs at 8 weeks of gestation.
d. Gastrointestinal system is mature at 32 weeks of gestation.
ANS: A
The heart is developmentally complete by the end of the embryonic stage. Hematopoiesis begins in the liver during the sixth week. The body becomes C-shaped at 21 weeks of gestation. The gastrointestinal system is complete at 36 weeks of gestation.