To characterize the variability of hormonal profiles during the luteal phase in normal cycles.
Design
Observational study.
Setting
Not applicable. PATIENT(S): Ninety-nine women contributing 266 menstrual cycles. INTERVENTION(S): The women collected first morning urine samples that were analyzed for estrone-3-glucuronide, pregnanediol-3-alpha-glucuronide (PDG), FSH, and LH. The women had serum P tests (twice per cycle) and underwent ultrasonography to identify the day of ovulation. MAIN OUTCOME MEASURE(S): The luteal phase was divided into three parts: the early luteal phase with increasing PDG (luteinization), the midluteal phase with PDG ≥10 μg/mg Cr (progestation), and the late luteal phase (luteolysis) when PDG fell below 10 μg/mg Cr. RESULT(S): Long luteal phases begin with long luteinization processes. The early luteal phase is marked by low PDG and high LH levels. Long luteinization phases were correlated with low E1G and low PDG levels at day 3. The length of the early luteal phase is highly variable between cycles of the same woman. The duration and hormonal levels during the rest of the luteal phase were less correlated with other characteristics of the cycle. CONCLUSION(S): The study showed the presence of a prolonged pituitary activity during the luteinization process, which seems to be modulated by an interaction between P and LH. This supports a luteal phase model with three distinct processes: the first is a modulated luteinization process, whereas the second and the third are relatively less modulated processes of progestation and luteolysis.
To examine whether luteal E2 is obligatory for obtaining an adequately developed endometrium. Survey of women with premature ovarian failure (POF) in a prospective, controlled, randomized study. In vitro fertilization unit in a tertiary care university medical center. Fourteen amenorrheic women with POF, candidates for oocyte donation, were divided into two distinct groups with seven women in each subgroup. Endometrial priming with a fixed dose of oral micronized E2, 4 mg/d for 14 days, was similarly performed in the study and the control groups. Progesterone replacement during the luteal phase was also identical in the two groups and was accomplished by IM P in oil, 50 mg/d for another 14 days. Only the control group continued to have the same E2 regimen during the luteal phase. Follicular phase mean E2 levels as well as luteal phase mean P levels were similar in both groups. However, luteal E2 levels differed significantly between the study and the control groups (21 +/- 5 and 692 +/- 199 pg/mL, respectively; conversion factor to SI units, 3.671). Nevertheless, histologic evaluation of endometrial biopsies on days 21 and 26 were similar for both groups. Endometrial gland dating, using light microscopy in the study and the control groups, on day 21, was 19.1 +/- 0.8 and 18.4 +/- 0.5, respectively, and on day 26, 25.4 +/- 0.8 and 25.9 +/- 0.5, respectively. Dating of the stroma in the two biopsies was also similar in both groups. Moreover, transmission electron microscopy performed in two patients of the study group showed typical characteristics of a secretory endometrium. Luteal E2 depletion in the human does not seem to adversely affect the morphological developmental capacity of the endometrium. Our results suggest that E2 secretion by the corpus luteum in the human does not appear to be obligatory for the development of a normal secretory endometrium. The actual receptivity of the endometrium after such preparation needs to be evaluated.
In 20 fertile women one menstrual cycle was monitored by ovarian ultrasonography, laparoscopy, and estimation of 17 beta-estradiol (E2) and progesterone levels in serum and peritoneal fluid (PF). Three groups were studied, performing the laparoscopy within 1, 3, and 5 days after ovulation. The results indicate that the opening in the corpus luteum remains at least during the first 1.5 postovulatory days. The process of the closure starts thereafter and has been accomplished 4 to 5 days after ovulation. Progesterone and E2 levels in PF follow a similar pattern, showing high levels in the first, decreasing levels in the second, and low levels in the last laparoscopy groups. Therefore the significance of inspection of the ovaries and hormone level estimation in PF depend on the timing of the laparoscopy in relation to the moment of ovulation, especially in the first 5 postovulatory days.
Tamoxifen at a dose of 10 mg/day for 5 days was given to five infertile women in the luteal phase. Daily serum samples were obtained during the luteal phase for radioimmunoassay of progesterone (P), estradiol (E2), follicle-stimulating hormone, luteinizing hormone (LH), and prolactin levels. The integrated luteal phase concentrations of serum P and E2 before and after cycles of tamoxifen treatment increased from 87.8 +/- 16.2 ng/ml and 1120 +/- 164.4 pg/ml to 131.6 +/- 18.9 ng/ml and 1461 +/- 205.2 pg/ml, respectively (P less than 0.01 and P less than 0.05). No apparent increase in circulating LH levels was seen in one of the five cases, but this patient's serum P and E2 levels rose nonetheless. This suggests that the significant increase in circulating P and E2 induced by tamoxifen is not consistently associated with an increase in serum LH concentration.
The corpus luteum is a vital yet temporary organ that plays a crucial role in fertility during the luteal phase. An endocrine structure in females exists within the ovary once the ovarian follicle releases a mature ovum during ovulation. See Image. Anatomy of the Internal Structures of the Ovary. The secretion of hormones from the corpus luteum stops within 14 days after ovulation if the oocyte is not fertilized. It then degenerates into a scar within the ovary, known as corpus albicans. The corpus luteum's role is to maintain a uterine environment that allows for implementation and pregnancy. This occurs by the release of pregnancy-related hormones and regulation of the hypothalamic-pituitary access through inhibition of gonadotropin-releasing hormone from the hypothalamus, which in turn decreases the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) released from the anterior pituitary. The primary hormone produced by the corpus luteum is progesterone, but it also produces inhibin A and estradiol. In the absence of fertilization, the corpus luteum regresses over time. A corpus luteum develops each time a woman ovulates so that she produces a corpus luteum numerous times throughout her lifetime.