Velde, E.R. te

Advanced maternal age, short interpregnancy interval, and perinatal outcome (Article)

2011-05-01T00:00:00Z

Objective: The purpose of this study was to evaluate whether the association between short interpregnancy intervals and perinatal outcome varies with maternal age. Study Design: We performed a retrospective cohort study among 263,142 Dutch women with second deliveries that occurred between 2000 and 2007. Outcome variables were preterm delivery (<37 weeks of gestation), low birthweight in term deliveries (<2500 g) and small-for-gestational age (<10th percentile for gestational age on the basis of sex- and parity-specific Dutch standards). Results: Short interpregnancy intervals (<6 months) was associated positively with preterm delivery and low birthweight, but not with being small for gestational age. The association of short interpregnancy interval with the risk of preterm delivery was weaker among older than younger women. There was no clear interaction between short interpregnancy interval and maternal age in relation to low birthweight or small for gestational age. Conclusion: The results of this study indicate that the association of short interpregnancy interval with preterm delivery attenuates with increasing maternal age.

Is human fecundity declining in Western countries? (Article)

2010-06-01T00:00:00Z

Since Carlsen and co-workers reported in 1992 that sperm counts have decreased during the second half of the last century in Western societies, there has been widespread anxiety about the adverse effects of environmental pollutants on human fecundity. The Carlsen report was followed by several re-analyses of their data set and by many studies on time trends in sperm quality and on secular trends in fecundity. However, the Results of these studies were diverse, complex, difficult to interpret and, therefore, less straightforward than the Carlsen report suggested. The claims that population fecundity is declining and that environmental pollutants are involved, can neither be confirmed nor rejected, in our opinion. However, it is of great importance to find out because the possible influence of widespread environmental pollution, which would adversely affect human reproduction, should be a matter of great concern triggering large-scale studies into its causes and possibilities for prevention. The fundamental reason we still do not know whether population fecundity is declining is the lack of an appropriate surveillance system. Is such a system possible? In our opinion, determining total sperm counts (as a measure of male reproductive health) in combination with time to pregnancy (as a measure of couple fecundity) in carefully selected populations is a feasible option for such a monitoring system. If we want to find out whether or not population fecundity will be declining within the following 20-30 years, we must start monitoring now.

Letter to the Editor of Human Reproduction Update (Article)

2009-10-01T00:00:00Z

Can assisted reproductive technologies help to offset population ageing? (Article)

2008-09-01T00:00:00Z

Expected poor ovarian response in predicting cumulative pregnancy rates: A powerful tool (Article)

2008-01-01T00:00:00Z

Poor ovarian response in IVF cycles is associated with poor pregnancy rates. Expected poor responders may represent the worst prognostic group. Data were used from 222 patients starting the first of three IVF treatment cycles. The predictability of ongoing pregnancy after three cycles was analysed using survival analysis and hazard rate ratios. If first cycle poor responders were also predicted to have a poor response, they were classified as expected poor responders. The predicted pregnancy rate in cycles 2 and 3 for women with an observed poor response in the first cycle was ∼24% for women aged 30 years and ∼14% for women aged 40 years. For women with an expected poor response these rates were 12% and 6%, respectively. In contrast, women aged 40 years with an unexpected poor response still had a predicted cumulative pregnancy rate of 24%. Age as a sole predictor of cumulative pregnancy does not help to identify poor prognosis cases. Cumulative pregnancy rates in subsequent cycles for patients with an observed poor response in the first cycle may be a reason to refrain from further treatment. However, if such poor response has been expected, further treatment may be avoided because of an unfavourable prognosis for pregnancy.

A case study of the applicability of a prediction model for the selection of patients undergoing in vitro fertilization for single embryo transfer in another center (Article)

2007-06-01T00:00:00Z

Objective: To evaluate the application in a different fertility clinic of a prediction model for selecting IVF patients for elective single embryo transfer. Design: Retrospective analysis of a large database obtained from a tertiary infertility center. Setting: University medical center. Patient(s): The model, derived at the "development center" was applied in 494 consecutive first IVF cycles carried out at the "application center.". Intervention(s): After adjustment of embryo scoring system to be compatible with that used by the prediction model, it was applied to the development center data. A score chart for predicting the probability of singleton or twin pregnancy was constructed. Main Outcome Measure(s): The area under the receiver operator curve (ROC) was determined to measure the ability of the model to discriminate between ongoing pregnancy and twin pregnancy. Calibration plots were made to assess agreement between predicted and observed pregnancy rates (PR). Results: The areas under the ROC for predicting ongoing pregnancy and twin pregnancy were 0.63 and 0.66, respectively. Insertion of a correction factor equivalent to the difference in odds ratios for ongoing PR between the two centers was required to improve the calibration of the model. Conclusion(s): After adaptation, the model performed well in the application center.

A mild treatment strategy for in-vitro fertilisation: a randomised non-inferiority trial (Article)

2007-03-03T00:00:00Z

Background: Mild in-vitro fertilisation (IVF) treatment might lessen both patients' discomfort and multiple births, with their associated risks. We aimed to test the hypothesis that mild IVF treatment can achieve the same chance of a pregnancy resulting in term livebirth within 1 year compared with standard treatment, and can also reduce patients' discomfort, multiple pregnancies, and costs. Methods: We did a randomised, non-inferiority effectiveness trial. 404 patients were randomly assigned to undergo either mild treatment (mild ovarian stimulation with gonadotropin-releasing hormone [GnRH] antagonist co-treatment combined with single embryo transfer) or a standard treatment (stimulation with a GnRH agonist long-protocol and transfer of two embryos). Primary endpoints were proportion of cumulative pregnancies leading to term livebirth within 1 year after randomisation (with a non-inferiority threshold of -12·5%), total costs per couple up to 6 weeks after expected date of delivery, and overall discomfort for patients. Analysis was by intention to treat. This trial is registered as an International Standard Randomised Clinical Trial, number ISRCTN35766970. Findings: The proportions of cumulative pregnancies that resulted in term livebirth after 1 year were 43·4% with mild treatment and 44·7% with standard treatment (absolute number of patients=86 for both groups). The lower limit of the one-sided 95% CI was -9·8%. The proportion of couples with multiple pregnancy outcomes was 0·5% with mild IVF treatment versus 13·1% (p<0·0001) with standard treatment, and mean total costs were €8333 and €10745, respectively (difference €2412, 95% CI 703-4131). There were no significant differences between the groups in the anxiety, depression, physical discomfort, or sleep quality of the mother. Interpretation: Over 1 year of treatment, cumulative rates of term livebirths and patients' discomfort are much the same for mild ovarian stimulation with single embryos transferred and for standard stimulation with two embryos transferred. However, a mild IVF treatment protocol can substantially reduce multiple pregnancy rates and overall costs.

Two new prediction rules for spontaneous pregnancy leading to live birth among subfertile couples, based on the synthesis of three previous models. (Article)

2004-09-01T00:00:00Z

BACKGROUND: Several models have been published for the prediction of spontaneous pregnancy among subfertile patients. The aim of this study was to broaden the empirical basis for these predictions by making a synthesis of three previously published models. METHODS: We used the original data from the studies of Eimers et al. (1994), Collins et al. (1995) and Snick et al. (1997) on couples consulting for various forms of subfertility. We developed a so-called three-sample synthesis model for predicting spontaneous conception leading to live birth within 1 year after intake based on the three data sets. The predictors used are duration of subfertility, women's age, primary or secondary infertility, percentage of motile sperm, and whether the couple was referred by a general practitioner or by a gynaecologist (referral status). The performance of this model was assessed according to a 'jack-knife' analysis. Because the post-coital test (PCT) was not assessed in one of the samples, a synthesis model including the PCT was based on two samples only. RESULTS: The ability of the synthesis models to distinguish between women who became pregnant and those who did not was comparable to the ability of the one-sample models when applied in the other samples. The reliability of the predictions by the three-sample synthesis model was somewhat better. Predictions improved considerably by including the PCT. CONCLUSIONS: The synthesis models performed better and had a broader empirical basis than the original models. They are therefore better suitable for application in other centres.

Towards less confusing terminology in reproductive medicine: a proposal. (Article)

2004-07-01T00:00:00Z

The use of the term "infertility" and related terms in reproductive medicine is reviewed. Current terminology is found to be ambiguous, confusing and misleading. We recommend that the fertility investigation report of a couple should consist of statements concerning description, diagnosis and prognosis. The description concerns the duration of non-pregnancy before consulting the clinician. A system for prognostic grading is proposed. The fertility investigation report forms the basis for further action, including the possibility of waiting with treatment in case of almost normal or only slightly reduced fertility. The use of the terms infertility, subfertility and fecundity is not necessary, and it is recommended to avoid them.

Predictors of chances to conceive in ovulatory patients during clomiphene citrate induction of ovulation in normogonadotropic oligoamenorrheic infertility (Article)

1999-01-01T00:00:00Z

The present prospective follow-up study was designed to identify whether clinical, endocrine, or ultrasound characteristics assessed by standardized initial screening of normogonadotropic oligo/amenorrheic infertile patients could predict conception in 160 women who reached ovulation after clomiphene citrate (CC) medication. Additional inclusion criteria were total motile sperm count of the partner above 1 million and a negative history for any tubal disease. Daily CC doses of 50 mg (increasing up to 150 mg in case of absent ovarian response) from cycle days 3-7 were used. First conception (defined as a positive urinary pregnancy test) was the end point for this study. A cumulative conception rate of 73% was reached within 9 CC-induced ovulatory cycles. Patients who did conceive presented more frequently with lower age (P < 0.0001) and amenorrhea (P < 0.05) upon initial screening. In a univariate analysis, patients with elevated initial serum LH concentrations (>7.0 IU/L) had a higher probability of conceiving (P < 0.01). In a multivariate analysis, age and cycle history (oligomenorrhea vs. amenorrhea) were identified as the only significant parameters for prediction of conception. These observations suggest that there is more to be gained from CC ovulation induction in younger women presenting with profound oligomenorrhea or amenorrhea. Screening characteristics involved in the prediction of ovulation after CC medication in normogonadotropic oligo/amenorrheic patients (body weight and hyperandrogenemia, as shown previously) are distinctly different from predictors of conception in ovulatory CC patients (age and the severity of cycle abnormality). This disparity suggests that the FSH threshold (magnitude of FSH required for stimulation of ongoing follicle growth and ovulation) and oocyte quality (chances for conception in ovulatory cycles) may be differentially regulated.

Predictors of patients remaining anovulatory during clomiphene citrate induction of ovulation in normogonadotropic oligoamenorrheic infertility (Article)

1998-01-01T00:00:00Z

The diagnostic criteria used to identify patients suffering from polycystic ovary syndrome remain controversial. The present prospective longitudinal follow-up study was designed to identify whether certain criteria assessed during standardized initial screening could predict the response to ovulation induction with clomiphene citrate (CC) in 201 patients presenting with oligomenorrhea or amenorrhea and infertility. Serum FSH levels were within the normal range (1-10 IU/L), and all patients underwent spontaneous or progestin-induced withdrawal bleeding. Initial CC doses were 50 mg daily for 5 days starting on cycle day 3. In the case of an absent response, doses were increased to 100 and 150 mg daily in subsequent cycles. First ovulation with CC was used as the end point. After a complete follow-up (in the case of a nonresponse, at least 3 treatment cycles with daily CC doses up to 150 mg), 156 patients (78%) ovulated. The free androgen index (FAI = testosterone/sex hormone-binding globulin ratio), body mass index (BMI), cycle history (oligomenorrhea vs. amenorrhea), serum androgen (testosterone and/or androstenedione) levels, and mean ovarian volume assessed by transvaginal sonography were all significantly different (P < 0.01) in responders from those in nonresponders. FAI was chosen to be the best predictor in univariate analysis. The area under the receiver operating characteristics curve in a multivariate prediction model including FAI, BMI, cycle history, and mean ovarian volume was 0.82. Patients whose ovaries are less likely to respond to stimulation by FSH due to CC treatment can be predicted on the basis of initial screening characteristics, such as FAI, BMI, cycle history (oligomenorrhea or amenorrhea), and mean ovarian volume. These observations may add to ongoing discussion regarding etiological factors involved in ovarian dysfunction in these patients and classification of normogonadotropic anovulatory infertile women.