Which of the following are common discomforts typically experienced during the first trimester of pregnancy? Select all that apply.

Backache in pregnancyis mainly due to relaxin-induced ligament laxity, lumbar lordosis, and increased mechanical strainfrom fetal growth. Relaxin peaks in the first trimester and remains elevated, softening the pubic symphysis and sacroiliac joints to prepare for childbirth. This increased joint mobility reduces pelvic and spinal stability, predisposing to lumbosacral pain. Additionally, weight gain (11.5–16 kg normal for BMI 18.5–24.9) and shift of the center of gravity increase lordotic curvature, straining paraspinal muscles.

Rationale for correct answers

2.Relaxation of pelvic ligaments and joints due to relaxin decreases pelvic stability, contributing to lumbosacral and back pain in pregnancy. This hormonal effect, combined with postural changes, explains the musculoskeletal discomfort commonly reported.

Rationale for incorrect answers

1.Lumbar lordosis actually increases, not decreases, in pregnancy due to the anterior shift in center of gravity. This worsens back strain but is not decreased as stated.

3.Reduced maternal weight gain would lessen, not worsen, back strain. It is excessive weight gain that increases musculoskeletal discomfort.

4.Abdominal muscle strength decreases as the uterus enlarges, further reducing core support. Increased strength would help prevent backache, not cause it.

Take home points

• Pregnancy backache results from relaxin-induced ligamentous laxity and increased lumbar lordosis.
• Mechanical load from fetal growth and maternal weight gain exacerbates pain.
• Reduced abdominal muscle tone worsens postural instability.
• Important differentials include urinary tract infection and preterm labor, which can also present with back pain.

Iron deficiency anemia in pregnancyis the most common cause of excessive fatigue, due to hemodilution, increased iron demand, and reduced oxygen deliveryto tissues. Plasma volume increases by 40–50%, while red blood cell mass rises only 20–30%, causing physiologic anemia. Normal hemoglobin in pregnancy is ≥11 g/dL in the 1st and 3rd trimesters and ≥10.5 g/dL in the 2nd trimester; hematocrit should be ≥33%. Symptoms include pallor, fatigue, tachycardia, and decreased exercise tolerance. Severe cases increase maternal morbidity and risk of preterm birth.

Rationale for correct answers

2.Iron deficiency anemia reduces hemoglobin concentration and oxygen-carrying capacity of the blood, leading to tissue hypoxia. This is the most common pathological cause of persistent fatigue in pregnancy, beyond the normal physiologic tiredness.

Rationale for incorrect answers

1.Hyperthyroidism in pregnancy more often causes weight loss, palpitations, heat intolerance, and tremors, rather than isolated fatigue. It is much less common than anemia.

3.Elevated estrogen levels are normal in pregnancy and contribute to vascular changes and uterine growth. They do not directly cause severe fatigue.

4.Decreased progesterone levels are not typical in healthy pregnancy; instead, progesterone levels rise steadily. Low progesterone would threaten pregnancy but is not a cause of common fatigue.

Take home points

• Iron deficiency anemia is the leading cause of pathological fatigue in pregnancy.
• Hemoglobin <11 g/dL (1st/3rd trimester) or <10.5 g/dL (2nd trimester) defines anemia.
• Plasma volume expansion creates physiologic anemia, but iron deficiency worsens it.

Differentiate fatigue from thyroid disorders or depression in pregnancy.