Maternal adaption to pregnancy

Question 1

What are the key reasons for maternal adaptation during pregnancy? (3)

Answer 1

• Response to physiological stimuli by the fetus or fetal tissues.
• To enable the mother to meet the increasing metabolic demands of the fetus.
• To cope with the stresses of pregnancy.

Question 2

What are the common symptoms during pregnancy? (7)

Answer 2

• Amenorrhea.
• Morning sickness (rarely lasts beyond 3rd month).
• Constipation.
• Fatigue.
• Enlargement of the abdomen.
• Increased frequency of micturition. (uterine enlargement causes pressure on bladder)
• Breast discomfort.

Question 3

What are the clinical signs of pregnancy? (4)

Answer 3

1. Breasts: Engorgement with dilatation of superficial veins,

• prominent areola (hyperpigmentation due to MSH by placenta)
• Montgomery’s tubercles are prominent
• secretion as early as 8 weeks.
  2. Abdomen: Uterus as a pelvic organ until 12 weeks.
  3. Pelvic changes:
• Chadwick’s sign: Dusky blue color of the cervix visible at about 8 weeks.
• Goodell’s sign: Softening of the cervix.
• Hegar’s sign: Uterus feels soft and elastic between 6-19 weeks.
  4. Fetal movements and fetal heart sounds.

Question 4

What are the methods used for the diagnosis of pregnancy? (2)

Answer 4

1. Immunological test: Agglutination reaction with antigen (b-HCG).
2. Sonography:
   - Gestational sac by 5th week.
   - Cardiac motion by 7th week.

Question 5

Which systems are affected by pregnancy? (9)

Answer 5

• Reproductive system.
• Cardiovascular system.
• Respiratory system.
• Renal system.
• Endocrine system.
• Hematological system.
• Gastrointestinal system.
• Musculoskeletal system.
• Integumentary system.

Question 6

What changes occur in the uterus during pregnancy? (6)

Answer 6

1. When pregnant at term the uterus is :
   Size- 35cm in length
   weight- 1000g
   position- dextrorotation, dextrodeviation
   shape- globular (8-16 weeks), pyriform (16weeks to term)
   consistency- progressively soft
   capacity- >5L
2. Uterine enlargement mainly due to hypertrophy (estrogen effect) rather than hyperplasia.
3. Symmetrical enlargement more in the fundus.
4. Progressive increase in utero-placental blood flow (500-800ml/min in late pregnancy).
5. Uterus landmarks:
   - Pubic symphysis at 12 weeks.
   - Umbilicus at 20 weeks.
   - Xiphisternum at 36 weeks.
6. Drops after 36 weeks as a sign of engagement.

Question 7

What changes occur in the cervix during pregnancy? (4)

Answer 7

1. Softening (Goodell’s sign) and increase in width.
2. Purple/cyanosed appearance (Chadwick’s sign).
3. Proliferation of glands through hypertrophy and hyperplasia.
4. Formation of mucous plug (operculum).

Question 8

What changes occur in the vulva during pregnancy?(3)

Answer 8

• Becomes vascular and hypertrophied.
• Visible superficial varicosities.
• Labia minora become pigmented and hypertrophied.

Question 9

What changes occur in the vagina during pregnancy? (3)

Answer 9

• Bluish coloration of the mucosa (Jacquemier’s sign) due to increased blood supply.
• Copious secretions.
• pH becomes acidic (3.5-6) due to lactic acid production.

Question 10

What changes occur in the ovaries during pregnancy?

Answer 10

Ovulation ceases because of the persistence of corpus luteum supporting early pregnancy stages.

Question 11

What changes occur in the breasts during pregnancy?

Answer 11

• Increase in size, nodularity, and sensitivity.
• Enlargement due to alveolar proliferation and fat deposition.
• Enlargement of Montgomery’s tubercles.
• Colostrum secretion (yellowish).

Question 12

How does cardiac output change during pregnancy? (4)

Answer 12

• Increases by 30% to 50% during pregnancy.
• Most increase (about 40%) occurs during the first trimester.
• Peaks at 30%-50% by the end of the 2nd trimester.
• 10% of cardiac output is directed to the fetal-placental unit.

Question 13

what causes the increase in cardiac output

Answer 13

• increase in stroke volume which is then maintained by increase in HR (10b/m)

Question 14

how is cardiac output affected by maternal positioning (3)

Answer 14

• Highest cardiac output in the lateral recumbent position
• In the supine position Cardiac output d decreases by 30% this is due to pressure of gravid uterus on IVC
• in the standing position there is a decreases by 20% due to pooling of blood in the legs

Question 15

what happens to the BP in mid -trimester

Answer 15

Systolic and diastolic Bp decrease and then gradual recovery by term.

Question 16

If woman dont show a fall in Bp during the mid trimester what does that mean

Answer 16

that they are at increased risk of developing gestational hypertension or preeclampsia.

Question 17

What changes occur in the respiratory system during pregnancy? (5)

Answer 17

1. 30% to 40% increase in tidal volume despite a 5% decrease in total lung capacity due to diaphragm elevation.
2. Decrease in expiratory reserve volume by about 20%, due to increase in TV
3. Increase in minute ventilation by 30% to 40%.
4. Decrease in PaCO2 levels to approximately 30 mm Hg by 20 weeks.
5. Dyspnea of pregnancy occurs in 60% to 70% of patients.

Question 18

what is significant about the decrease in PaCO2 in the mother? (2)

Answer 18

• This change leads to an increased CO2 gradient between mother and fetus and is likely caused by elevated progesterone levels that either increase the respiratory system’s responsiveness to CO2 or act as a primary stimulant.
• This gradient facilitates oxygen delivery to the fetus and carbon dioxide removal from the fetus.

Question 19

What changes occur in the renal system during pregnancy? (3)

Answer 19

1. Kidneys increase in size and ureters dilate, increasing pyelonephritis risk.
2. Glomerular filtration rate (GFR) increases by 50% early in pregnancy.
   - As a result of increased GFR, blood urea nitrogen and creatinine decrease by about 25%.
3. Bladder pressure by uterus leads to:
   - hydronephrosis and hydroureter
   - frequency of micturition.
   - Urinary stasis which favors infection.
   - stress incontinence

Question 20

what things do you check for in urine analysis (3)

Answer 20

-glucosuria
- hematuria
- proteinuria

Question 21

What endocrine changes occur during pregnancy? (4)

Answer 21

1. Levels of estrogen and progesterone increase.
2. Increased hepatic production of thyroid-binding globulin (TBG).
   - which causes more free T3 and T4 to bind to the TBG
   - which then causes more TSH to be released from the anterior pituitary gland
   -however free T3 and T4 levels remain unchanged, therefore the total T3 and T4 levels increase
   - Thyroxine is important for fetal neural development. Fetal thyroid gland is not functional until the second trimester of gestation hence T3 and T4 supply thyroxin to the fetus from the mother in early pregnancy
3. Anti-insulin hormones (human placental lactogen, prolactin, cortisol) increase during the second trimester, increasing insulin resistance.
   - Reduce peripheral uptake of glucose this ensures that there is a continuous supply of glucose for the fetus.
4. The mother switches to an alternative source of energy:
   - Provided by lipids through lipolysis
   - ↑ in free fatty acids in the plasma for maternal metabolism.
   - The breakdown of lipids can result in ketogenesis
   - Thus, pregnancy is associated with anincreased risk ofketoacidosis.

Question 22

What hematological changes occur during pregnancy? (4)

Answer 22

1. 50% increase in blood volume, 20% increase in red blood cells hence leading to hemodilution anemia and reduced hematocrit
2. WBC count increases during pregnancy (6-16 million), can reach up to 20 million/mL during labor due to stress.
3. Slight decrease in platelet concentration, probably secondary to increased plasma volume and an increase in peripheral destruction.
4. Pregnancy is a hypercoagulable state with increased thromboembolic events.
   - There is elevation in Fibrinogen by 50% and Factors VIII, VII, IX,X and XII increased.
   - Fibrinolytic activity is decreased
   - There is also an increase in venous stasis and vessel endothelial damage
   - Prothrombin time (PT), Activated partial thromboplastin time (APTT) shortened

Question 23

What immunologic changes occur during pregnancy? (4)

Answer 23

• Bidirectional traffic of fetal and maternal cells.
• 30% of women develop IgG antibody against paternal human leukocyte antigen.
• Reduced numbers of cytotoxic (CD8) T cells during pregnancy resulting in lack of maternal immune reactivity to the foetus
• Marked increase in leukocytes, especially polymorphonuclear leukocytes.

Question 24

what are the benefits of a hypercoagulable state in pregnancy? (2)

Answer 24

• reduces risk of hemorrhage during child birth (helps with hemostasis)
• prevent excessive bleeding from minor injuries

Question 25

What gastrointestinal changes occur during pregnancy? (5)

Answer 25

1. Nausea and vomiting (morning sickness) occur in more than 70% of pregnancies, usually resolve by 14-16 weeks.
2. Increased intragastric pressure leads to gastrointestinal reflux, nausea, vomiting ( stomach is displaced upwards)
3. Progesterone increases smooth muscle relaxation leading to:
   - constipation
   - Gastric emptying and intestinal transit time decreased
   - Allows more time for nutrient absorption
4. Hemorrhoids due to elevated intra-abdominal pressure.
5. Gums may become soft and bleed easily, can form epulis; focal, soft, highly vascular swellings

Question 26

What musculoskeletal changes occur during pregnancy? (4)

Answer 26

• Increase in body weight leading to a forward shift center of gravity then increasing Lumbar lordosis.
• Increase in intraabdominal pressure then diastasis of recti
• Relaxation of the pelvic girdle ligaments and symphysis due to relaxin and progesterone leading to pelvic girdle pain and coccygeal pain.
• Fluid retention in tissue may lead to carpal tunnel syndrome

Question 27

What dermatologic changes occur during pregnancy? (2)

Answer 27

• Abdomen: Striae gravidarum, Linea nigra.
• Face: Chloasma.