Correct Answer: B

Rationale: The correct answer is B: Low acidity levels which favor growth of candida albicans. During pregnancy, hormonal changes can lead to increased vaginal pH, creating a more alkaline environment that promotes the growth of candida albicans, causing vulvovaginitis. Choice A is incorrect as E. coli thrives in alkaline environments. Choice C, existing chronic hypertension, is unrelated to the development of vulvovaginitis. Choice D, lowered osmotic pressure, does not directly influence the growth of candida albicans.

Correct Answer: C

Rationale: The correct answer is C: Not more than two previous caesarean section scars. This is because a trial of scar refers to a trial of labor in a woman who has had previous cesarean sections. The guideline typically recommends that a trial of scar should be considered in women with no more than two previous cesarean section scars to reduce the risk of uterine rupture. Choices A, B, and D are incorrect because the estimated fetal weight, availability of a level one hospital, and pelvis size are not specific criteria used to determine eligibility for a trial of scar.

Correct Answer: B

Rationale: The correct answer is B: Fetal exsanguination. This term accurately describes the process of pure fetal blood loss following a ruptured vasa praevia. Exsanguination refers to severe blood loss leading to death. In this context, it specifically denotes the loss of fetal blood due to the rupture of vasa praevia, which can be fatal for the fetus. A: Fetal extra-versation is not a recognized medical term and does not accurately describe the scenario presented in the question. C: Velamentous bleeding refers to a condition where fetal blood vessels are unprotected by the umbilical cord and run through the amniotic membranes, not specifically related to ruptured vasa praevia. D: Fetal hemorrhage is a general term for fetal blood loss and does not specifically address the situation of pure fetal blood loss following a ruptured vasa praevia.

Correct Answer: D

Rationale: The correct answer is D: Portal hypertension. In myelodysplastic syndromes, splenectomy is indicated primarily for portal hypertension due to extramedullary hematopoiesjson in the spleen, leading to increased blood flow and pressure in the portal vein. This can alleviate symptoms such as ascites and variceal bleeding. Choices A, B, and C are incorrect as major hemolysis, massive splenomegaly, and sustained leukocyte elevation are not primary indications for splenectomy in myelodysplastic syndromes.

Correct Answer: B

Rationale: The correct answer is B - Culture and level of education. Culture influences beliefs about pain and coping mechanisms. Education can affect understanding of pain and pain management techniques. Labor preparedness and fatigue (A) may impact pain perception but are not as influential. Age (C) alone does not determine pain perception. Number of deliveries and anxiety (D) can play a role but are not as significant as culture and education.