Question

The signals for parturition originate from

• A. Placenta only
• B. Oxytocin released from maternal pituitary
• C. Placenta as well as fully developed foetus
• D. Fully developed foetus only

Answer 1

The correct option is C

Placenta as well as fully developed foetus

The correct option is C

Explanation of the correct option:

1. A sophisticated neuroendocrine process causes parturition.
2. The placenta and the fully-grown fetus send signals to the uterus that cause the so-called fetal ejection reflex, or modest uterine contractions.
3. The maternal pituitary responds by releasing oxytocin.

Explanation of the incorrect options:
Option A:

1. The placenta and the fully-grown fetus signal the body to give birth.
2. Mild uterine contractions are referred to as the fetal ejection reflex.
3. Uterine contractions are brought on by this stimulating the posterior pituitary to release the hormone oxytocin.

Option B:

1. When the fetus is fully mature, signals from the placenta and fetus cause the uterine wall to contract.
2. The maternal pituitary gland receives signals from uterine contractions to release the oxytocin hormone.
3. Oxytocin causes uterine contractions to be strong, which forces the fetus outside.

Option D:

1. Additionally, oxytocin is utilized to lessen postpartum hemorrhage.
2. It can also be combined with other treatments or medications to stop a pregnancy.
3. A group of drugs known as oxytocin hormones includes oxytocin.

Final answer:
The signals for parturition originate from the placenta and fully developed fetus.