The placenta acts as an endocrine tissue and makes hCG, hPL, estrogens and progestogens. In the later phase of pregnancy, relaxin is made by the ovary (not the placenta). Memory hook: "Placenta = C-P-E-P (hCG, hPL, Estrogen, Progestogen); Relaxin is the Ovary's job."
The placenta secretes hCG, hPL, estrogens and progestogens; relaxin is secreted by the ovary (corpus luteum) in the later phase of pregnancy. hCG, hPL and relaxin appear only during pregnancy.
Your doubts, answered
Does the placenta secrete relaxin?
No. This is the most common NEET trap. NCERT clearly says relaxin is secreted by the ovary in the later phase of pregnancy. The placenta secretes hCG, hPL, estrogens and progestogens. So relaxin is NOT a placental hormone.
Which hormones does the placenta secrete according to NCERT?
The placenta produces hCG (human chorionic gonadotropin), hPL (human placental lactogen), estrogens and progestogens. The word to remember from NCERT is 'etc.', but for NEET options stick to these four. If an option adds relaxin or oxytocin to the placenta, it is wrong.
What is the difference between hCG and hPL?
Both are made by the placenta, but hCG (human chorionic gonadotropin) maintains the corpus luteum so it keeps making progesterone in early pregnancy. hPL (human placental lactogen) helps the mother's metabolism and prepares the body for supporting the foetus. Both are made ONLY during pregnancy.
Which hormones are produced only during pregnancy?
NCERT says hCG, hPL and relaxin are produced in women only during pregnancy. This is a favourite one-liner in NEET. Note relaxin is on this list even though its source (ovary) is different from hCG and hPL (placenta).
Are estrogen and progesterone levels high in pregnancy?
Yes. During pregnancy the levels of estrogens, progestogens, cortisol, prolactin and thyroxine increase several-fold in the maternal blood. These support foetal growth, changes in the mother's body, and the maintenance of pregnancy.
⚠️ The NEET trap ✗ Relaxin is one of the hormones secreted by the placenta. ✓ Relaxin is secreted by the ovary in the later phase of pregnancy. The placenta secretes hCG, hPL, estrogens and progestogens. 🧠 In NEET 2018 the correct option 'hCG, hPL, progestogens, estrogens' was chosen and every option that put relaxin under placenta was wrong. Placenta does NOT make relaxin.
Real NEET questions
2016
Several hormones like hCG, hPL, estrogen, progesterone are produced by
A · Ovary
B · Placenta ✓
C · Fallopian tube
D · Pituitary
Solution: NCERT states the placenta acts as an endocrine tissue and produces hCG, hPL, estrogens and progestogens. These are placental hormones, so the answer is Placenta.
2018
Hormones secreted by the placenta to maintain pregnancy are
A · hCG, hPL, progestogens, estrogens ✓
B · hCG, hPL, estrogens, relaxin, oxytocin
C · hCG, hPL, progestogens, prolactin
D · hCG, progestogens, estrogens, glucocorticoids
Solution: The placenta secretes hCG, hPL, estrogens and progestogens. Relaxin is made by the ovary and oxytocin/prolactin are not placental, so only option A is fully correct.
2021
Which of the following secretes the hormone, relaxin, during the later phase of pregnancy?
A · Foetus
B · Uterus
C · Graafian follicle
D · Corpus luteum ✓
Solution: NCERT says relaxin is secreted by the ovary in the later phase of pregnancy. The ovarian structure at that time is the corpus luteum, so corpus luteum is the accepted answer.
Solved Human Reproduction NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Yes, NCERT says the placenta acts as an endocrine tissue. It is a temporary endocrine gland that works only during pregnancy and secretes hCG, hPL, estrogens and progestogens.
What does hCG do?
hCG (human chorionic gonadotropin) keeps the corpus luteum active so it continues to make progesterone in early pregnancy. It is also the hormone detected by pregnancy test kits.
Is relaxin a placental hormone?
No. Relaxin is secreted by the ovary in the later phase of pregnancy. It is NOT made by the placenta, though it IS made only during pregnancy.
What is a common temporary endocrine gland asked in NEET?
The corpus luteum and the placenta are both temporary endocrine glands. In NEET 2017, the answer to 'a temporary endocrine gland' was the corpus luteum.
Why do estrogen and progesterone rise during pregnancy?
Their several-fold rise supports foetal growth, drives metabolic changes in the mother, and maintains the pregnancy by keeping the uterus ready.
