Chapter 11: Maternal Adaptation During Pregnancy Flashcards Preview

OB Pedi > Chapter 11: Maternal Adaptation During Pregnancy > Flashcards

Flashcards in Chapter 11: Maternal Adaptation During Pregnancy Deck (35)
Loading flashcards...

Presumptive signs

Subjective and signs that mother can perceive.
Breast tenderness
nausea and vomiting
urinary frequency hyperpigmentation of the skin
fetal movement
uterine enlargement
breast enlargement


Probable signs of pregnancy

Can be detected with physical examination.
Braxton Hicks contractions from 16 to 28 weeks.
Positive pregnancy test from 4 to 12 weeks.
Abdominal enlargement around 14 weeks.
Ballottement around 16 to 28 weeks.
Goodells sign around five weeks. Chadwicks sign around 6 to 8 weeks.
Hegars sign around 6 to 12 weeks.


Positive signs of pregnancy

The only signs with 100% accuracy Ultrasound verification of embryo or fetus 4 to 6 weeks.
Fetal movement felt by experienced clinician at 20 weeks.
Auscultation of fetal heart tones via a Doppler around 10 to 12 weeks.


Goodell's sign

Softening of the cervix 6 -8 weeks


Chadwick's sign

Bluish/purple coloration of the vaginal mucosa and cervix. This is from an increased vascularization of the cervix



Examiner pushes against the women's cervix during a pelvic examination and feels a rebound from the floating fetus.



Corresponds to morning sickness around 6 to 12 weeks. Levels double every 48 to 72 hours until peak around 60 to 70 days after fertilization. After that they declined to a plateau around 100 to 130 days. Doubling time can be used to differentiate normal and abnormal gestation

Maintains the maternal corpus luteum, which secretes progesterone and estrogen, with synthesis occurring before implantation


Uterus adaptations

Estrogen stimulates uterine growth. Remains in the pelvic cavity for the first three months and then slowly ascends into the abdomen. The uterus begins as a pear-shaped, becomes ovoid. By 20 weeks the fundus is at the level of umbilicus and measures 20 cm. Fundal height usually corresponds with the weeks between 18 and 32. Between 38 and 40 weeks fetus begins to descend and fundal height drops.


Braxton Hicks contractions

Spontaneous, irregular, and painless contractions that began during the first trimester and continue throughout. During the last month they function testing to thin out or efface the cervix before birth.


Hegar's sign

Softening and compressibility of the lower uterine segment during the first 6 to 8 weeks. Adds to urinary frequency


Maternal supine hypotensive syndrome

When the mom is in a supine position, the uterus lies on the inferior vena cava resulting in compression. This decreases cardiac output and blood pressure and increases orthostatic hypotension. Symptoms include weakness, lightheadedness, nausea, dizziness, or syncope


Cervix adaptations

Cervix softens around 6 to 8 weeks. The mucous glands increase. Progesterone causes a thick mucous plug that blocks the cervical os and protects the opening. There's an increase in vascularization. Softening and effacement begins about four weeks before birth.


Vaginal adaptations

Vascularity increases because of estrogen. Mucosa thickens, the vaginal vault lengthens, secretions become more acidic, white, and thick. Increase in discharge called leukorrhea. This increases the risk for Candida albicans.


Ovary adaptations

Increased vascularity causes them to enlarge until around 12 to 14 weeks. Ovulation ceases because of increased estrogen and progesterone. They are important in hormone production until 6 to 7 weeks, when the corpus luteum regresses and the placenta takes over.



Excessive salivation


G.I. system adaptations

The gums become swollen and tend to bleed easily. This is influenced by estrogen. Increased in Saliva. Dental plaque, and gingivitis increase. Progesterone causes a decrease peristalsis. This leads to constipation There is decreased gastric emptying leading to indigestion or heartburn (pyrosis). Emptying of the gallbladder is prolonged leading to gallstones.


Cardiovascular system changes

Blood volume: increases by 1500 mL or about 50%

Cardiac output: increases from 30% to 50%. The heart rate increases.

Blood-pressure: declines slightly as a result of dilation caused by progesterone. The low is at mid pregnancy.

Blood components: red blood cells increase. Plasma increases even more leading to hemodilution. This causes anemia. Iron supplements are given


Respiratory system adaptations

Respirations increase and become more deep. Oxygen consumption increases. There is an increase vascularity leading to congestion.


Renal/urinary system adaptations

Kidneys enlarge, glomerular filtration rate increases, urine flow and volume increase.


Integumentary system changes

Estrogen and progesterone cause hyperpigmentation. Complexion changes leading to the mask of pregnancy. There is the Linea nigra from the umbilicus to the pubic area. Striae gravidarum are stretch marks. Varicosities of the legs, vulva, and perineum. Spider veins, palmer erythema, decreased hair growth and loss of hair.


Thyroid gland

Enlarges slightly and becomes more active. Increased thyroid production of T4 is needed for neural development of the fetus. It's also increases metabolic rate


Pituitary gland/hypophysis

Enlarges during pregnancy and produces multiple hormones. FSH and LH are inhibited. TSH inhibited. GH decreases. Prolactin increases for breast development and lactation. MSH Melanocyte stimulating hormone increases and may be responsible to the skin changes

Oxytocin responsible for contractions, milk ejection. Progesterone decreases in later pregnancy allowing oxytocin contractions.

ADH plays a role in water balance and blood pressure


The pancreas

During pregnancy glucose levels of the mom decrease because of the fetus needing glucose. Insulin levels also decline early on. Insulin does not cross the placenta and the fetus produces its own. Towards the end of the pregnancy more insulin is secreted to counteract the hormones that oppose it.


Adrenal glands

Cortisol increases in response to increased estrogen. This helps the level of glucose, breakdown proteins to repair tissues, has an anti-Insulin, anti-inflammatory, and antiallergic actions. Is needed to make adrenaline.

Aldosterone increases to regulate electrolytes and water balance.


Placental hormones




Prepares memory glands, helps make glucose available for fetal growth, antagonist of insulin, increases the amount of circulating free fatty acids, decreases the maternal metabolism of glucose



Secreted by the placenta and the corpus luteum. Acts synergistically with progesterone to maintain pregnancy. Increases flexibility of the pubic symphysis. Dilation of the cervix, may suppress the release of oxytocin



The hormone of pregnancy because it supports the endometrium of the uterus. Provides an environment conducive to fetal survival. Initially produced by the corpus luteum Initially causes thickening of the uterine lining to make implantation ready. Maintains the endometrium, inhibits uterine contractions, assists in breast development



Promotes enlargement of the genitals, uterus, breasts, increases vascularity, vasodilation, relaxes the pelvic ligaments and joints, hyperpigmentation, increased saliva, hyperemia of the gums, aids in breast development.


Immune system adaptations

Enhancement of innate immune which is inflammatory and phagocytosis

Suppression of adaptive which is antigen response

This helps the mom to not reject fetus, but increases her risk for infection.