Analysis of clinical fertility trials: a methodologic review

Validation study of nonsurgical diagnosis of endometriosis

Eskenazi B et al., 2001 · Fertil Steril

To determine whether the surgical diagnosis of endometriosis can be predicted using symptoms, signs, and ultrasound findings. Prospective study (study sample); retrospective record review (test sample). Hospital of Desio (study sample) and Mangiagalli Hospital (test sample), Italy. PATIENT(S): Ninety women scheduled to undergo laparoscopy or laparotomy (study sample); 120 women who underwent laparoscopy (test sample). The study sample group was interviewed before surgery about infertility and dysmenorrhea, dyspareunia, and noncyclic pelvic pain and each member had a pelvic examination and a transvaginal ultrasound. At surgery, endometriosis was noted. For the test sample, the same information was abstracted from medical records after laparoscopy. MAIN OUTCOME MEASURE(S): The ability of symptoms, signs, and ultrasound to predict endometriosis at surgery. A classification tree was developed with the study sample and evaluated with the test sample. RESULT(S): Ovarian endometriosis, but not nonovarian endometriosis, could be reliably predicted with noninvasive tools. Ultrasound and examination best predicted ovarian endometriosis, correctly classifying 100% of cases with no false positive diagnoses in the study sample. Similar results were found in the test sample. CONCLUSION(S): Noninvasive tools may be used to identify women with ovarian, but not nonovarian endometriosis, with excellent agreement with surgical diagnosis.

Polycystic ovary syndrome: pathophysiology and outcome with in vitro fertilization

Buyalos RP et al., 1996 · Fertil Steril

To assess the efficacy of IVP-ET in infertile women with the polycystic ovary syndrome (PCOS) and to provide a comprehensive review of contemporary therapeutic options and their complications as reflected in the current literature. Pertinent studies in medical literature identified through computerized bibliographic search and via manual review of relevant scientific publications. In vitro fertilization and ET is an effective therapy for PCOS patients who are refractory to ovulation induction in vivo or who have coexisting infertility factors. The use of GnRH agonist (GnRH-a) is associated with significant reductions in the incidence of pregnancy loss and may improve fertilization and cleavage rates. In the PCOS patient, the use of purified FSH preparations does not appear to improve pregnancy rates nor other clinical parameters when compared with hMG. Severe ovarian hyperstimulation syndrome (OHSS) is an important consideration when PCOS patients undergo superovulation protocols. Strategies for OHSS prevention include the use of intravenous albumin immediately after oocyte retrieval, triggering of ovulation with a GnRH-a, or withholding menotropin therapy for several days before hCG administration. Cryopreservation of all embryos for future transfer in an artificial cycle has also proven to be an effective alternative in PCOS patients at high risk for severe OHSS. Pregnancy rates for PCOS patients undergoing IVF-ET are comparable with those for women with tubal factor infertility. Therefore, IVF-ET should be offered to patients with PCOS who are refractory to conventional infertility modalities.

Myomectomy for fertility enhancement and preservation

Verkauf BS, 1992 · Fertil Steril

To review, evaluate, and synthesize current published reports assessing the value of abdominal myomectomy in infertile women and those desiring to preserve fertility potential. Major studies dealing with myomectomy were identified through Medline Searches. Those papers reporting the results of myomectomy, factors influencing them, and potential future innovations were obtained. More than half of women not previously pregnant and undergoing myomectomy to preserve childbearing capacity for treatment of recurrent pregnancy wastage or previous infertility conceive. The long duration of infertility before surgery, absence of other factors to explain their not conceiving, and short time interval subsequent to surgery in which conception occurs suggests myomectomy has value in treatment of patients with leiomyomata and otherwise unexplained infertility. The operation carries acceptable risk. Approximately 25% of women undergoing myomectomy have recurrent leiomyomata, but most recurrences are sufficiently delayed to allow adequate opportunity for conception. Abdominal myomectomy is an appropriate alternative to hysterectomy for most women who wish to preserve childbearing potential or enhance it. For the future, myomectomy by endoscopic techniques may hold similar potential.

Current concepts of beta-endorphin physiology in female reproductive dysfunction

Seifer DB et al., 1990 · Fertil Steril · Free to read

beta-Endorphin has a role in the regulation of the normal menstrual cycle and possibly in the onset of puberty. We have reviewed the evidence pointing to an alteration in this neuropeptide that may contribute to the pathogenesis of various reproductive dysfunctions. Elevated or high levels of beta-endorphin have been associated with exercise-associated amenorrhea, stress-associated amenorrhea, and polycystic ovarian syndrome. Depressed or low levels of beta-endorphin have been associated with PMS and menopause. Alterations in the levels of beta-endorphin may change the pulsatile release of GnRH via noradrenergic and/or dopaminergic pathways. We have primarily focused on beta-endorphin as representative of the endogenous opioid peptides, but other opioid peptides may also contribute to the pathogenesis of various types of reproductive dysfunction. Perhaps it will become possible to characterize and hone our understanding of the function of beta-endorphin and the other substances composing the endogenous opioid peptides. A better understanding of their role in physiological as well as pathophysiological processes may allow for the development of rational approaches to the treatment of specific disorders pertaining to reproduction. Many questions remain unanswered. Among the most relevant are: what is the precise mechanism of action by which beta-endorphin exerts its influence on pulsatile GnRH release? Is there a functional relationship between CNS and peripheral (serum) levels of beta-endorphin? Are the detected changes in beta-endorphin levels merely associated, or are they a cause of a particular disorder? Since it took almost 40 years between the time prostaglandins were first discovered and eventual realization of their clinical application, it may take some time before the beta-endorphin story is complete.

S28.3: Validity of methods used to estimate the effectiveness of Emergency Contraception

Mikolajczyk RT et al., 2004 · Biometrical J

Statistical evaluation of contraceptive methods: Use-effectiveness and extended use-effectiveness

Lewit S et al., 1968 · Demography

The recent advent of national family planning programs and the expansion of local programs have created an acute need for accurate statistical evaluation of contraceptive methods. Effectiveness in terms of pregnancy rates and continuation or discontinuation of use of the contraceptive method or methods under study have emerged as the major criteria in such evaluations.

Statistical methods in evaluating the outcome of infertility therapy

Cramer DW et al., 1979 · Fertil Steril

Lack of standardization in analytic methods for assigning infertility data is attributed to inadequate classification of fertility problems, and a lack of consistent methodology in evaluating outcome of infertility therapy. A classification scheme ideally should consider types of fertility problems as well as clinical assessment of its severity. Until an adequate classification system is developed, researchers are encouraged to describe fully the nature of infertility problem examined, and present results for homogenous groups of patients. The life-table method of analysis is a useful technique for assessing infertility statistics. The starting point of this method should depend on the group examined and may be either the date of 1st visit to the clinic or the date that therapy is instituted. Approximate date of conception should be the endpoint. A mathematical model of infertility predicated on the assumption that there is a constant monthly probability of conception of fecundability can be used to derive equations with potential for clinical application.

Methodologic and statistical approaches to studying human fertility and environmental exposure

Tingen C et al., 2003 · Environ Health Perspect · Free full text on PubMed Central

Although there has been growing concern about the effects of environmental exposures on human fertility, standard epidemiologic study designs may not collect sufficient data to identify subtle effects while properly adjusting for confounding. In particular, results from conventional time to pregnancy studies can be driven by the many sources of bias inherent in these studies. By prospectively collecting detailed records of menstrual bleeding, occurrences of intercourse, and a marker of ovulation day in each menstrual cycle, precise information on exposure effects can be obtained, adjusting for many of the primary sources of bias. This article provides an overview of the different types of study designs, focusing on the data required, the practical advantages and disadvantages of each design, and the statistical methods required to take full advantage of the available data. We conclude that detailed prospective studies allowing inferences on day-specific probabilities of conception should be considered as the gold standard for studying the effects of environmental exposures on fertility.