Which phase of the endometrial cycle coincides with the luteal phase?
Menstrual phase
Proliferative phase
Secretory phase
Regenerative phase
The Correct Answer is C
The endometrial cycle aligns with the ovarian cycle and consists of three main phases: menstrual, proliferative, and secretory. The secretory phase coincides with the luteal phase of the ovarian cycle and spans approximately days 15–28. It is regulated primarily by progesterone (normal mid-luteal: 5–20 ng/mL) secreted by the corpus luteum. Progesterone stimulates the endometrial glands to secrete glycogen and other nutrients, making the endometrium thick, vascular, and receptive to implantation. Without fertilization, progesterone levels fall, leading to endometrial breakdown and the start of menstruation.
Rationale for correct answer
C. The secretory phase is driven by progesterone from the corpus luteum and prepares the endometrium for possible implantation. It occurs during the luteal phase of the ovarian cycle.
Rationale for incorrect answers
A. The menstrual phase coincides with the early follicular phase, not the luteal phase. It involves shedding of the functional layer of the endometrium due to hormone withdrawal.
B. The proliferative phase occurs during the follicular phase of the ovarian cycle. It is estrogen-driven and involves rebuilding the endometrium after menstruation.
D. The regenerative phase is not a standard term in the clinical classification of the endometrial cycle. The correct phases are menstrual, proliferative, and secretory.
Take home points
- The secretory phase matches the luteal phase and prepares the uterus for implantation.
- Progesterone from the corpus luteum drives the secretory changes.
- The proliferative phase aligns with follicular phase and is estrogen-dependent.
- Menstrual phase begins with hormone withdrawal and marks the end of the luteal phase.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is ["B","C","E"]
Explanation
Progesterone in the menstrual cycle Progesterone is a steroid hormone produced by the corpus luteum after ovulation during the luteal phase. Its primary role is to prepare the endometrium for implantation. Progesterone maintains the uterine lining, inhibits uterine contractions, and increases basal body temperature. Normal serum progesterone levels vary across the cycle: follicular phase <1 ng/mL, luteal phase 5–20 ng/mL, postmenopausal <0.5 ng/mL. It is also critical in modulating immune tolerance during early pregnancy.
Rationale for correct answers
B. Progesterone converts the endometrium from the proliferative to the secretory phase, enhancing glandular secretion and stromal edema to support implantation.
C. It inhibits myometrial contractions by reducing prostaglandin synthesis and promoting uterine quiescence during the luteal phase, preventing embryo expulsion.
E. Progesterone increases basal body temperature typically by 0.3–0.5°C due to its thermogenic effect on the hypothalamic temperature-regulating center.
Rationale for incorrect answers
A. Endometrial proliferation occurs during the follicular phase and is mediated primarily by estradiol. Progesterone opposes proliferation and promotes secretory transformation.
D. Ovulation is triggered by a surge in luteinizing hormone (LH), not progesterone. Progesterone secretion rises only after ovulation has occurred.
Take home points
- Progesterone maintains a secretory endometrium essential for embryo implantation.
- It inhibits uterine contractility by downregulating prostaglandins.
- Progesterone elevation correlates with the post-ovulatory rise in body temperature.
- Estradiol governs the proliferative phase; LH surge triggers ovulation.
Correct Answer is ["A","B","C"]
Explanation
Secretory phase of the menstrual cycle The secretory phase follows ovulation and is driven by progesterone from the corpus luteum, transforming the proliferative endometrium into a receptive environment for implantation. The endometrial glands become tortuous and begin secreting glycogen, while stromal edema and increased vascularity aid embryo nourishment. Spiral arteries elongate and become more coiled, and normal endometrial thickness during this phase ranges from 7–14 mm. Progesterone levels peak around 5–20 ng/mL in the mid-luteal phase.
Rationale for correct answers
A. Endometrial glands become tortuous due to progesterone influence, increasing their secretory capacity in preparation for embryo implantation.
B. Glycogen and mucus are secreted into the lumen to create a nutrient-rich medium essential for the survival and implantation of the embryo.
C. Progesterone enhances vascular permeability and stromal edema, making the endometrium highly vascular and edematous to support embryo development.
Rationale for incorrect answers
D. Shedding of the functional layer occurs during menstruation, not the secretory phase. Menstrual shedding begins only if fertilization does not take place, leading to corpus luteum regression and progesterone withdrawal.
E. Spiral arteries become more prominent and coiled during the secretory phase to support increased blood flow. Less prominence is incorrect; their hypertrophy is critical for placental development if implantation occurs.
Take home points
- Secretory phase is progesterone-dominant and follows ovulation.
- Tortuous glands and glycogen secretion prepare the endometrium for implantation.
- Spiral arteries elongate and coil for enhanced perfusion.
- Functional layer shedding occurs only in menstruation, not in the secretory phase.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.