Normal pregnancy: placental hormones: practice question

A OBG question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

OBG · Normal pregnancy: placental hormones

Sample item

Which statement about early placental hormone production is correct?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

B. The corpus luteum maintains progesterone until the luteoplacental shift at about 7 to 9 weeks

hCG from the syncytiotrophoblast rescues the corpus luteum, which makes progesterone until the placenta takes over at roughly 7 to 9 weeks. This is why luteectomy before this time can cause abortion. hCG peaks at 8 to 10 weeks and then falls.

Option by option

  • A. The placenta takes over oestrogen synthesis fully by itself using fetal precursors only from the first week

    Placental oestrogen needs fetal adrenal DHEA-S as precursor, and it is not independent in the first week.

  • B. The corpus luteum maintains progesterone until the luteoplacental shift at about 7 to 9 weeks (correct)

    Correct. This luteoplacental shift is why early corpus luteum removal causes loss.

  • C. hCG levels keep rising steadily until term

    hCG peaks at 8 to 10 weeks and falls afterwards.

  • D. Human placental lactogen is secreted by the cytotrophoblast

    hPL is produced by the syncytiotrophoblast, not the cytotrophoblast.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More OBG questions

Questions about this OBG question

What is the answer to this OBG question?

The best answer is B, The corpus luteum maintains progesterone until the luteoplacental shift at about 7 to 9 weeks. hCG from the syncytiotrophoblast rescues the corpus luteum, which makes progesterone until the placenta takes over at roughly 7 to 9 weeks.

Why is "The placenta takes over oestrogen synthesis fully by itself using fet…" not the answer?

Placental oestrogen needs fetal adrenal DHEA-S as precursor, and it is not independent in the first week.

Why is "hCG levels keep rising steadily until term" not the answer?

hCG peaks at 8 to 10 weeks and falls afterwards.

Why is "Human placental lactogen is secreted by the cytotrophoblast" not the answer?

hPL is produced by the syncytiotrophoblast, not the cytotrophoblast.

What concept does this question test?

It tests Normal pregnancy: placental hormones in OBG. This is why luteectomy before this time can cause abortion. hCG peaks at 8 to 10 weeks and then falls.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Normal pregnancy: placental hormones?

Learn management algorithms as steps: PPH, eclampsia, ectopic pregnancy. Then use the flashcards and the other OBG questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.