Rene Leiva

• MD
• Professor (Assistant) at University of Ottawa

Objective: There is considerable individual day-to-day variation within the menstrual cycle and between cycles in women. Average hormone curves inadequately describe the individual hormone patterns experienced by women. The present study applies a novel application of a statistical array (heat map) to demonstrate both individual and group menstrual...

Smartphone-based fertility awareness methods with home-based urinary hormonal testing are gaining popularity for fertility tracking. In our university-affiliated family practice, we integrated a previously developed ovulation tracking application into a protocol for monitoring urinary sex hormones and cervical secretions. Serum progesterone was use...

Study question: What is the effect of oestrogen and progesterone at the beginning of the menstrual cycle in delaying entry into the fertile window? Summary answer: Both oestrogen and progesterone contribute to a delay in the onset of the fertile window. What is known already: Oestrogen enhances cervical mucus secretion while progesterone inhib...

Objectives During normal menstrual cycles, serum levels of progesterone vary widely between cycles of same woman and between women. This study investigated the profiles of pregnanediol during the luteal phase. Methods Data stemmed from a previous multicenter prospective observational study and concerned 107 women (who contributed 326 menstrual cyc...

Objective Describe the relationship between basal body temperature (BBT) and pregnanediol-3 alpha-glucuronide (PDG, the urine metabolite of progesterone) across the menstrual cycle. Design: Observational study. Setting: Study carried out from 1996 to 1997 in eight European family planning clinics. Participant(s): One hundred and seven normally fert...

Rationale Ovulation confirmation is a fundamental component of the evaluation of infertility. Purpose To inform the design of a larger clinical trial to determine the effectiveness of a new home-based pregnanediol glucuronide (PDG) urine test to confirm ovulation when compared with the standard of serum progesterone. Methods In this observational...

[This corrects the article DOI: 10.3389/fpubh.2017.00320.].

Objective: Explore potential relationships between preovulatory, periovulatory, and luteal-phase characteristics in normally cycling women. Design: Observational study. Setting: Eight European natural family planning clinics. Patient(s): Ninety-nine women contributing 266 menstrual cycles. Intervention(s): The participants collected first morning u...

Background: Even in normally cycling women, hormone level shapes may widely vary between cycles and between women. Over decades, finding ways to characterize and compare cycle hormone waves was difficult and most solutions, in particular polynomials or splines, do not correspond to physiologically meaningful parameters. Objective: We present an ori...

Objective To study the best possible luteinizing hormone (LH) threshold to predict ovulation within the 24, 48, and 72 h. Design Observational study. Setting Multicenter collaborative study. Patients A total of 107 women. Interventions Women collected daily first morning urine for hormonal assessment and underwent serial ovarian ultrasound. Thi...

Objective 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-...

Introduction Even in normally cycling women, the shapes of hormone levels may widely vary between cycles and between women. Over the last decades, finding ways to characterize and compare the cycle hormone waves has shown to be a very difficult task and most answers, in particular polynomials or splines, do not refer to physiologically meaningful p...

Downie’s commentary on physician-assisted suicide states that “as a profession we must ensure that there are physicians willing and able” to further this end once it is legal and regulated.1 Over two millennia ago, the Hippocratic Oath described how the push to end our patients’ lives was evident even back then: “I will not give a lethal drug to an...

In 2002, Belgium became the second country in the world to legalize euthanasia. A few studies dealing with the Belgium euthanasia practices have been published, based on a survey given to a sample of physicians and nurses. These studies have implicitly proposed the practice of euthanasia as a medical act. Moreover, an article published in the Journ...

To assess the sensitivity and specificity of the self-identified fertile window. Observational study. Not applicable. A total of 107 women. Women recorded cervical mucus observation and basal body temperature daily while undergoing daily ovarian ultrasound. The biological fertile window, defined as the 6 days up to and including the day of ovulatio...

Purpose: Difficult clinical signs such as confusing cervical mucus or erratic basal body temperature can make the use of fertility awareness methods (FAMs) difficult in some cases. The goal of this study was to assess the feasibility of using a cheap urinary luteinizing hormone (LH)-surge identification kit as an adjunct to identify the infertile p...

To describe FSH profile variants. Observational study. Multicenter collaborative study. A total of 107 women. Women collected daily first morning urine and underwent serial ovarian ultrasound. The individual FSH cyclic profiles demonstrated a significant departure from the currently accepted model. A decline in FSH levels at the end of the follicul...

Urinary hormonal markers may assist in increasing the efficacy of Fertility Awareness Based Methods (FABM). This study uses urinary pregnanediol-3a-glucuronide (PDG) testing to more accurately identify the infertile phase of the menstrual cycle in the setting of FABM. Secondary analysis of an observational and simulation study, multicentre, Europea...

Cognitive status has been reported to be an important predictor of rehabilitation outcome. The Montreal Cognitive Assessment (MoCA) was designed to overcome some of the limitations of established cognitive screening tools such as the Mini-Mental State Examination (MMSE). The purpose of this study is to evaluate the psychometric characteristics of t...

http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61251-2/fulltext Leiva R. Maternal mortality and abortion. Lancet. 2010 Aug 14;376(9740):515.

To report a case of successful treatment of complete retrograde ejaculation by use of a novel, simple, and noninvasive home-based protocol. Case report. Private family medicine clinic. A couple with primary infertility due to the male's complete retrograde ejaculation due to childhood's bladder surgery. The woman was healthy with normal menstrual c...