Pieternel Steures

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BACKGROUND Intrauterine insemination with controlled ovarian hyperstimulation is commonly used as first-line treatment for couples with unexplained subfertility. Since such treatment increases the risk of multiple pregnancy, a couple's chances of achieving an ongoing pregnancy without it should be considered to identify those most likely to benefit from(More)
BACKGROUND Obesity is increasing rapidly among women all over the world. Obesity is a known risk factor for subfertility due to anovulation, but it is unknown whether obesity also affects spontaneous pregnancy chances in subfertile, ovulatory women. METHODS We evaluated whether obesity affected the chance of a spontaneous pregnancy in a prospectively(More)
BACKGROUND Prediction models have been developed in reproductive medicine to help assess the chances of a treatment-(in)dependent pregnancy. Careful evaluation is needed before these models can be implemented in clinical practice. METHODS We systematically searched the literature for papers reporting prediction models in reproductive medicine for three(More)
Lipoprotein lipase (LPL) is a key enzyme in lipoprotein metabolism, and has been hypothesized to exert either pro- or anti-atherogenic effects, depending on its localization. Decreased plasma LPL activity is associated with the high triglyceride (TG);-low HDL phenotype that is often observed in patients with premature vascular disease. In contrast, in the(More)
OBJECTIVE To determine the precise degree of variability that is represented by the reproducibility and reliability of semen analysis. The general assumption is that semen analyses need to be repeated because of a high degree of within-individual variability. However, the precise degree of variability is not well established in male partners of subfertile(More)
BACKGROUND In the past 20 years, various recommendations have been made about the maximum number of intrauterine insemination (IUI) cycles that should be performed, because evidence underpinning a possible limit is lacking. METHODS We performed a multicentre, retrospective cohort analysis among couples treated with IUI up to nine cycles. Primary outcome(More)
OBJECTIVE To assess the effectiveness of controlled ovarian hyperstimulation (COH) in intrauterine insemination (IUI) for subfertile couples with an abnormal postcoital test and a poor prognosis. DESIGN Randomized clinical trial. SETTING Twenty-four fertility centers in the Netherlands. PATIENT(S) Subfertile couples with a well-timed nonprogressive(More)
BACKGROUND Intrauterine insemination (IUI) is a commonly used treatment in subfertile couples. We assessed patients' preferences for IUI relative to expectant management. METHODS Forty subfertile couples were offered scenarios in which the treatment-independent pregnancy chance was varied against a fixed pregnancy chance after IUI without or with(More)
BACKGROUND Conventional meta-analysis has estimated the sensitivity and specificity of hysterosalpingography (HSG) to be 65% and 83%. The impact of patient characteristics on the accuracy of HSG is unknown. The aim of this study was to assess by individual patient data meta-analysis whether the accuracy of HSG is associated with different patient(More)
BACKGROUND Laparoscopy has been claimed to be superior to hysterosalpingography (HSG) in predicting fertility. Whether this conclusion is applicable to a general subfertile population can be questioned as data in support of this claim were collected in third line centres. The aim of this study was to assess the prognostic capacity of HSG and laparoscopy in(More)