Appendicitis: This is a common cause of right lower quadrant pain in pregnancy, especially in the second trimester. The growing uterus can displace the appendix to a higher position, but the pain typically remains in the right lower quadrant.

Urinary Tract Infection (UTI): UTIs are common in pregnancy due to physiological changes that can predispose to infection. Symptoms can include right lower quadrant pain, dysuria, and frequency.
Kidney Stones: Although less common in pregnancy, kidney stones can cause severe right lower quadrant pain, often radiating to the groin, and can be associated with nausea and vomiting.
Ovarian Cyst or Torsion: Ovarian cysts can cause right lower quadrant pain, and torsion is a complication that can occur, especially in pregnancy due to the displacement of the ovaries by the growing uterus.

Ectopic Pregnancy: Although less likely in the second trimester, an ectopic pregnancy can present with right lower quadrant pain and is a life-threatening condition if missed.
Placental Abruption: This condition involves the premature separation of the placenta from the uterus and can cause abdominal pain, including right lower quadrant pain, and vaginal bleeding.
Uterine Rupture: Although rare, uterine rupture can occur in the second trimester, especially in women with a history of uterine surgery, and can present with severe abdominal pain.

Hepatic Hemangioma or Adenoma: These are benign liver tumors that can cause right upper quadrant pain but can occasionally refer pain to the right lower quadrant.
Inflammatory Bowel Disease (IBD) Flare: Conditions like Crohn's disease or ulcerative colitis can cause right lower quadrant pain, especially if the disease involves the terminal ileum.
Diverticulitis: Although more common in older populations, diverticulitis can occur in pregnant women and cause right lower quadrant pain, especially if the diverticula are located in the sigmoid colon.