Learning Objectives
1. Identify the components of preconceptional care and state the nursing considerations related to preconceptional care.
2. Describe the processes of conception, implantation, and placental development.
3. Differentiate the major events of the development of the embryo and the growth of the fetus.
4. Describe the structure and function of the placenta, umbilical cord, fetal membranes, and amniotic fluid.
5. Outline the pathway of fetal blood circulation.
6. Contrast the presumptive, probable, and positive signs of pregnancy. State the significant nursing considerations for each.
7. Describe the changes in a woman’s anatomy and physiology that occur during each trimester of pregnancy.
8. Discuss anticipatory guidance for pregnant women related to changes in the body’s structure and function.
9. Identify the major teaching concepts related to prenatal care.
10. Prepare a nursing care plan teaching healthy lifestyle behaviors for pregnant women.
11. Identify recommended nutritional guidelines during pregnancy.
12. Describe the major and minor discomforts of pregnancy, how they might be alleviated, and how a woman can differentiate them from more serious problems.
13. Summarize the major nursing considerations and nursing interventions for the pregnant woman.
14. Explore ways to support preparing for parenthood and expanding the family.
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IMPORTANT TERMINOLOGY |
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amnion |
ductus venosus |
lactation |
placenta |
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amniotic fluid |
embryo |
linea nigra |
preconception |
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antepartum |
fetoscope |
lordosis |
prenatal |
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anticipatory guidance |
fetus |
melasma |
primigravida |
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ballottement |
foramen ovale |
morula |
ptyalism |
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cephalocaudal |
fundal height |
multifetal |
quickening |
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Chadwick’s sign |
gestation |
multigravida |
trimester |
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chorion |
Goodell’s sign |
Nägele’s rule |
ultrasound |
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colostrum |
grand multipara |
nurse midwife |
umbilicus |
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conception |
gravida |
obstetrician |
viable |
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congenital |
Hegar’s sign |
obstetrics |
Wharton’s jelly |
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decidua |
hyperemesis |
para |
zygote |
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Doppler |
gravidarum |
pica |
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ductus arteriosus |
implant |
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Acronyms |
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BBT |
PIH |
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BMI |
PMP |
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CNM |
PPD |
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EDC |
PPROM |
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EDD |
PROM |
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HCG |
PTL |
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HPL |
RhoGAM |
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LMP |
STD |
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LNMP |
TST |
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MSAFP |
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During the woman’s reproductive years, the female body is designed for conceiving and bearing children. Every month, it experiences a complex system of hormonal and physical changes for the sole purpose of producing an egg and supporting the earliest days of pregnancy. When pregnancy does not occur, the woman has a menstrual period. When the egg that is produced meets with a sperm, and conception occurs, she becomes pregnant. This initiates a sequence of events that, if all goes well, will result in the birth of a healthy infant.
Key Concept Pregnancy is a normal physiologic process, not a disease.
In this topic, you will learn about normal healthy pregnancy, the amazing changes that occur in the woman’s body during pregnancy, and the process of human development. You will learn how to help the client experience the healthiest pregnancy possible, and prepare her for the changes in her life and family that are soon to come.
DEFINING PREGNANCY AS A NORMAL PROCESS
Gestation is the period of time that occurs from the moment a man’s sperm fertilizes a woman’s egg until the birth of the newborn. Fertilization usually occurs 2 weeks after a woman’s last normal menstrual period (LMP or LNMP) .The total length of gestation, including these 2 weeks, is 40 weeks (10 lunar months, or 9 calendar months). Based on the common use of the calendar year, pregnancy is divided into three 3-month periods (trimesters). If we break these trimesters into weeks, the first trimester begins on the first day of the woman’s last period and ends on the last day of week 13. The second trimester includes weeks 14 through 27, and the third trimester begins at week 28 and extends until the pregnancy is expected to end at 40 weeks.
During the 40 weeks of pregnancy, the woman may be referred to as a gravida, the Latin term for a pregnant woman. If it is her first pregnancy, she is a primigravida; if she has had other births, she is a multigravida. The word para refers to the parting of mother and baby, or the birth itself. A woman who has given birth many times (specifically, at least five times), is called a grand multipara. See In Practice: Data Gathering in Nursing 65-1 for details on classifying a woman’s pregnancy history.
Pregnancy is also called the antepartum period; therefore, prenatal care (care before the birth) may also be called antepartum care. Prenatal care can be provided in a private practice, at a clinic, or at home. Good prenatal care is one of the most important factors in the health of mothers and babies. Even with the best prenatal care, it is possible for problems to occur; however, without adequate prenatal care, the risk for problems is much higher for both the mother and the baby.
Obstetrics is the branch of medicine concerned with pregnancy and birth. A physician who practices this specialty is called an obstetrician.
IN PRACTICE: DATA GATHERING IN NURSING 65-1
CLASSIFYING A WOMAN’S PREGNANCY HISTORY
Each woman’s pregnancy history is classified by a set of numbers known as gravida-para (or G-P).
G = Gravida: total number of pregnancies she has had, including this one if she is now pregnant P = Para: number of babies born at 20 or more weeks of gestation
Using this system, a woman who has had only one previous pregnancy which resulted in the birth of a baby at 38 weeks, and who is now pregnant would be G2 (two pregnancies), P1 (one birth).
Para (P), the outcome of her pregnancies, is further classified as follows. FPAL defines the outcomes of pregnancies in more detail:
F = Full term: number of babies born at 37 or more weeks of gestation
P = Preterm: number of babies born between 20 and 37 weeks of gestation A = Abortions: total number of spontaneous and elective abortions, including ectopic pregnancies, that ended before 20 weeks of gestation (The earliest gestational age that is considered viable, or able to survive if the fetus is born, is 20 weeks.) L = Living children, as of today Hint Remember the sequence by FPAL = Florida Power And Light (Note that some authors use the acronym TPAL, in which T = Term.)
Applying the expanded classification to describe a woman who is not now pregnant, but has had four pregnancies—two babies born at term, one preterm, and one miscarriage (spontaneous abortion), you would write G4 P2113.
A registered nurse who has received specialized training in the management of labor and birth is called a nurse midwife, or CNM (certified nurse midwife). Nurse midwives are specialists who work with healthy women during their pregnancies. They help them to maintain wellness, and attend at vaginal births. Most women who have serious health risks before pregnancy or who develop problems during their pregnancy are considered to be at higher risk and, therefore, are referred to an obstetrician. The goal of all healthcare professionals during pregnancy and birth is to assist the woman to give birth to a healthy newborn with the least possible danger and discomfort to both the mother and the child.
Preconceptional Care
Preconceptional care (care of the woman before she is pregnant) is an important healthcare priority. The goal of precon-ceptional care is to have the best possible pregnancy outcome for every mother and baby. This goal can be accomplished by performing a complete health assessment of the family and recommending any changes that will make the pregnancy safer for the mother as well as for the baby she will carry. It is important to perform preconceptional care because the earliest weeks of pregnancy are the most critical in human development. Another good reason to start care before pregnancy is that some of the most important changes are difficult to accomplish and take a lot of effort by the mother-to-be (e.g., better nutrition and the elimination of alcohol). Seven areas need to be addressed in pre-conceptional care:
1. Eating a healthy diet, including 400 mg (microgram, also seen as mcg) of folic acid a day.
2. Stopping harmful or addictive behaviors, such as smoking, drinking alcohol, or using drugs.
3. Stopping use of prescription drugs that are known to be harmful to a developing infant. Obtaining prescriptions for alternate drugs that are safer for use during pregnancy.
4. For the diabetic woman: Changing to insulin instead of an oral diabetic agent and making sure her blood sugar is under excellent control.
5. Referring a couple at risk of having a baby with a genetic defect for genetic testing and counseling before the pregnancy.
6. Testing the mother-to-be for infectious diseases, and either providing immunizations (e.g., rubella vaccine), or treating any infections that are found, including human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs).
7. Reducing psychosocial risk factors. For example, helping a woman who is being battered to find services and help or linking women with community resources.
For additional precautions, see In Practice: Educating the Client 65-1.
There are two types of preconceptional visits: (1) visits by a woman or couple planning a pregnancy, and (2) visits by a woman who is not planning to become pregnant soon but who may become pregnant. In the ideal world, every woman or couple would seek healthcare when they are in the planning stages, before a pregnancy occurs. However, every year many pregnancies in the United States are unintended or unplanned. Because of this reality, it is very unlikely that those women or families will seek preconceptional care. If we are committed to the best outcome for every mother and baby, we must treat every healthcare visit by a woman during her childbearing years as a preconceptional visit.
IN PRACTICE : EDUCATING THE CLIENT 65-1
PREGNANCY PRECAUTIONS
The following is a summary of essential precautions to discuss with each woman who is pregnant or who may become pregnant.
• Do not take any medication or drug, unless it was prescribed by a practitioner who knows that the client is trying to conceive or is already pregnant.
• Avoid x-rays whenever possible. If an emergency x-ray is indicated following an injury or due to a disease, it should not be refused because of pregnancy An abdominal/pelvic shield should be used whenever possible. The pregnant woman should inform both her healthcare provider and the x-ray technologist of her pregnancy Elective x-ray examinations should be deferred until after delivery.
• Avoid substance use, including limiting caffeine intake; avoiding tobacco in any form, including passive smoke exposure; and abstaining from alcohol and recreational drugs.
• Avoid or limit exposure to known environmental toxins.
• Avoid exposure to infections, including rubella, influenza, tuberculosis, and sexually transmitted infections (STIs).
• Avoid hyperthermia-producing situations, such as hot tubs, excessive exercise, or prolonged sitting in hot water (> I00°F).
Stages of Human Development
Conception and Sex Determination
Human life begins with the union of two cells: the ovum (female) and the sperm (male) (Fig. 65-1). This union, known as fertilization or conception, usually occurs when the ovum is in the outer third of the fallopian tube (oviduct). At the time of conception, the sperm determines the sex. An ovum carries only one type of chromosome to determine sex: the X chromosome. A male sperm cell may carry either an X or Y sex chromosome. If a sperm cell carrying a Y chromosome fertilizes the ovum, a boy (XY) will result; if the sperm cell carries an X chromosome, the result will be a girl (XX).
FIGURE 65-1 · Fertilization: the union of ovum and sperm.
FIGURE 65-2 · Blastocyst 7 to 8 days after fertilization.
Period of the Zygote and Implantation
The fertilized ovum, or zygote, is the beginning of potential individual human development. During this time, the zygote divides rapidly, until it forms a ball of about 16 identical cells, which is then called a morula. At this stage, the first differences among cells develop.
The morula is then swept down the fallopian tube and into the uterus, a process that takes approximately 7-9 days. The lining of the uterus, or endometrium, has become rich in nutrients in preparation for the pregnancy.
Just before the morula reaches the uterus, the cells begin to form layers; first one, then two layers surround a fluid-filled space, called a blastocyst (Fig. 65-2). Another group of cells form what will become the embryo. As the blastocyst enters the uterus, the outer cell layers secrete an enzyme that permits it to burrow (implant) into the endometrium (or, as it is known during pregnancy, the decidua). (See Fig. 65-3 for a diagram depicting early human development and implantation.)
