Normal probability plots were used to assess the homogeneity of a population of 327 luteal phases from apparently ovulatory menstrual cycles. The length of the luteal phase was defined as the interval (in days) following but not including, the luteinizing hormone peak, up to and including the day before onset of menstruation. A small sub-set of the population consisted of cycles with abnormally short luteal phases but the majority of the data followed a normal frequency distribution which gave a mean (+/- SD) for normal luteal phase length of 14.13 (+/- 1.41) days. It was estimated that all cycles with a luteal phase less than or equal to 9 days were abnormal, and that 74%, 22% and 2% respectively of cycles with luteal phases of 10, 11 and 12 days were also abnormal. The total incidence of short luteal phases defined as above was 5.2%.
normal luteal phase length variation menstrual cycle, short luteal phase definition diagnosis criteria, Lenton luteal phase length LH peak, luteal phase deficiency incidence ovulatory cycles, normal probability distribution luteal phase duration, short luteal phase less than 11 days frequency, LH peak to menstruation interval normal range, luteal phase length mean standard deviation population study, identifying abnormal short luteal phase cutoff days, ovulatory menstrual cycle luteal phase adequacy assessment
PMID 6743610 6743610 DOI 10.1111/j.1471-0528.1984.tb04831.x 10.1111/j.1471-0528.1984.tb04831.x
Cite this article
Lenton, E. A., Landgren, B. M., & Sexton, L. (1984). Normal variation in the length of the luteal phase of the menstrual cycle: identification of the short luteal phase. British journal of obstetrics and gynaecology, 91(7), 685-689. https://doi.org/10.1111/j.1471-0528.1984.tb04831.x
Lenton EA, Landgren BM, Sexton L. Normal variation in the length of the luteal phase of the menstrual cycle: identification of the short luteal phase. Br J Obstet Gynaecol. 1984;91(7):685-689. doi:10.1111/j.1471-0528.1984.tb04831.x
Lenton, E. A., et al. "Normal variation in the length of the luteal phase of the menstrual cycle: identification of the short luteal phase." British journal of obstetrics and gynaecology, vol. 91, no. 7, 1984, pp. 685-689.
Fourteen normal women (self-selected from 180 women enrolled) in a marathon training clinic kept basal body temperature (BBT), mileage, and weight records for 48 cycles before the marathon. Age 20-45, gynecologic age greater than 5 years, no hormone use, or weight change in 3 months. The women were 35.2 +/- 5.6 years in age, 22.6 +/- 5.1 years gynecologic age, runners of 4.1 +/- 2.5 years with premenstrual symptoms, previous pregnancy 4/14, no infertility and 2/14 remote amenorrhea. BBT records were obtained and analyzed by Vollman's criteria (1977). There was no weight loss. 32/48 cycles were biphasic but only 16 were normal in the length of the premenstrual phase (PreM = luteal, nl 10 - 16 d) with a mean of 11.1 +/- 1.2 days. The other 16 biphasic cycles had short PreM phase of 6.4 +/- 1.8 days. Monophasic (M = anovulatory) cycles occurred in 16/48 records. Cycles which were abnormal (Short PreM and M) differed only in that usual run length was longer (9.6 - 9.9 miles) than in normal cycles (7.9 +/- 2.4 miles). Marathon training may be associated with normal length but M and short PreM type cycles.
To test the association between cytokine levels in the amniotic fluid and (i) the vascular invasion phase of intrauterine infection, (ii) the occurrence of periventricular leukomalacia; to assess the correlation between C-reactive protein levels, a recognised biological marker of inflammation in maternal serum and cytokine levels in the amniotic fluid. Prospective clinical study. Fetal medicine unit and neonatal intensive care unit, Antoine Beclere Hospital, Clamart, France. Thirty-one pregnancies complicated by chorioamnionitis leading to birth before 32 weeks of gestation. Interleukin 1-beta, Interleukin 6 and TNF-alpha prospectively measured in the amniotic fluid. Histological examination of the placenta. Ultrasound examination and magnetic resonance imaging of the brains of the newborn infants performed within the first week of life. The occurrence of periventricular leukomalacia was assessed by transfontanellar ultrasound and magnetic resonance imaging. There was a significant positive correlation between the occurrence of histological chorioamnionitis, vascular extension of infection of the membranes, maternal inflammatory syndrome and neonatal sepsis. A strong association was found between maternal serum C-reactive protein concentrations and cytokine levels in the amniotic fluid. Interleukin-1beta was the best predictor of vascular extension of chorioamnionitis, and TNF-alpha was the best predictor of the development of severe early neonatal infection. There was no association between the amniotic fluid levels of cytokines and the development of periventricular leukomalacia. These data suggest that IL-1beta, IL-6 and TNF-alpha are produced in relation to intrauterine inflammation and infection, but cannot be directly implicated in the development of fetal cerebral white matter lesions.
To examine the risk of multiple sclerosis in users of combined oral contraceptives.
Cohort study conducted between 1968 and 1996 using diagnostic data supplied by General practices throughout the United Kingdom. Royal College of General Practitioners' Oral Contraception Study cohort of initially 46,000 women recruited during the late 1960s. Directly standardised incidence rates of multiple sclerosis were calculated for current, former and never-users of oral contraceptives using first ever cases of multiple sclerosis reported by the general practitioners. The standardisation variables were age, parity, social class and smoking history. Five-year survival rates in the different contraceptive groups were calculated using standard life table techniques. One hundred and fourteen first ever cases of multiple sclerosis had been reported by November 1996 during 564,000 woman-years of observation. The incidence rate in both current and former users was not materially different to that in never-users. Although based on limited evidence there was no suggestion that the five-year survival was affected by a woman's use of combined oral contraceptives. These findings do not suggest a greatly elevated risk of multiple sclerosis during, or after, use of combined oral contraceptives.