Conception, Fetal Development, and Maternal Nursing Care

Flashcards covering the vocabulary and key concepts of conception, fetal development, maternal physiological changes, nutritional requirements, and prenatal assessment methods.

Conception

The union of a single egg and single sperm, marking the beginning of a pregnancy.

Zonal reaction

A process taking place in the ampulla of the uterine tube where the membrane surrounding the ovum becomes impenetrable to other sperm after one sperm successfully penetrates.

Implantation

Occurs between $6-10$ days after conception when the trophoblast burrows into the endometrium until the entire blastocyst is covered.

Embryonic period

The stage from the end of the second week through the eighth week where basic structures of all major organs are completed and the embryo is most vulnerable to teratogens.

Chorion

The outermost embryonic membrane that encircles the amnion, embryo, and yolk sac, eventually becoming the covering of the fetal side of the placenta.

Amnion

The second embryonic membrane, originating from the ectoderm, which forms the inner layer of the "bag of waters."

Oligohydramnios

An abnormality where the volume of amniotic fluid is less than $300\,mL$.

Hydramnios (polyhydramnios)

An abnormality where the volume of amniotic fluid is more than $2000\,mL$.

Wharton’s Jelly

A specialized connective tissue that surrounds the three vessels (two arteries and one vein) within the umbilical cord.

Duncan side

The maternal side of the placenta used for circulation between the mother and the placenta.

Schultz side

The fetal side of the placenta where blood vessels converge to form the umbilical vessels.

Isoimmunization

A complication that may occur if fetal blood leaks into maternal circulation, causing the mother to develop antibodies to fetal RBCs.

Viable

The stage of fetal development, beginning around $24$ weeks, where the fetus is able to live outside the uterus with assistance.

$L/S$ ratio

A ratio used to determine fetal lung maturity; a ratio of $2:1$ is considered mature.

Meconium

Green fetal excrement formed in the GI tract that should typically be expelled within $24$ hours after birth.

Vernix

A white, thick, fatty substance on the fetal body that serves as a protective coating for the skin.

Lanugo

Fine hair that begins to develop on the fetus around $12$ weeks gestation.

Quickening

The first maternal recognition of fetal movement, typically felt between $16-20$ weeks gestation.

Lightening

The sensation occuring around $40$ weeks when the fetal head descends and the uterus sinks, often relieving shortness of breath.

Chadwick’s sign

A purplish appearance of the cervix and vagina caused by increased vascularity and blood congestion.

Goodell's sign

A softening of the cervix in response to pregnancy hormones to allow for eventual dilation.

Hegar’s sign

A softening of the lower uterine segment or uterine consistency.

Physiologic anemia of pregnancy

A condition resulting from a total blood volume increase of $40-50\%$, where plasma volume increases more than RBC volume.

Chloasma (Melasma)

Often referred to as the "Mask of pregnancy," it is hyperpigmentation of the face due to pregnancy hormones.

Linea nigra

A line of hyperpigmentation extending from the symphysis pubis to the top of the fundus.

Progesterone

The most important hormone for maintaining pregnancy; it maintains the endometrial layer, prevents spontaneous abortion/tissue rejection, and relaxes smooth muscle.

Naegele’s Rule

A method to estimate the due date by taking the first day of the Last Menstrual Period (LMP), subtracting $3$ months, and adding $7$ days.

Gravid (Gravida)

The total number of pregnancies a woman has had, including the current one.

Para

The number of pregnancies that have ended in delivery after $20$ weeks’ gestation, regardless of the number of fetuses.

PICA

A persistent craving and eating of nonnutritive substances, most commonly caused by iron deficiency anemia.

Biophysical profile (BPP)

An assessment of fetal well-being based on five variables: fetal heart rate acceleration, fetal breathing, fetal movements, fetal tone, and amniotic fluid volume.

Reactive Nonstress Test (NST)

A test result showing at least two fetal heart rate accelerations within a $20$ minute period, indicating a healthy fetus and intact CNS.

Negative Contraction Stress Test (CST)

A desired test result showing no late decelerations of the fetal heart rate in response to uterine contractions.

Witch’s milk

Secretions from the infant's breasts after birth related to high levels of maternal estrogen.