What is the primary purpose of using pethidine?

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: During the 34-40 weeks of pregnancy, Montgomery's tubercles become prominent. These are sebaceous glands on the areola, not the nipples. Choice A is incorrect as it describes the changes in nipples, not Montgomery's tubercles. Choice B is incorrect as colostrum production usually starts around the 16th week. Choice C is incorrect as breast tenderness is more common in early pregnancy due to hormonal changes.

Correct Answer: B

Rationale: Incomplete abortion is characterized by an open os, which means that the cervix is dilated, allowing for passage of tissue. This condition typically presents with heavy bleeding as parts of the products of conception are expelled. Severe cramping may also be present due to uterine contractions. Therefore, the correct characteristic of incomplete abortion is an open os (Choice B). Choices A, C, and D are incorrect as heavy bleeding and severe cramping are symptoms associated with incomplete abortion, but they do not specifically define it, and light bleeding is not characteristic of incomplete abortion.

Correct Answer: A

Rationale: During an ectopic pregnancy, a rupture in the ampullary portion of the tube is frequent. This is due to the increased pressure within the fallopian tube as the embryo grows, leading to the rupture of the tube. Choices B, C, and D are incorrect as they do not accurately describe the common occurrence of rupture in this specific part of the tube during an ectopic pregnancy.

Correct Answer: B

Rationale: The correct answer is B: Haemorrhage. Haemorrhage is a leading cause of maternal mortality due to excessive bleeding during childbirth. While conditions like pre-eclampsia, sepsis, and obstructed labor can also be serious complications during pregnancy and childbirth, they are not the primary cause of maternal mortality worldwide.