R.J. van Kooij

Pesticide exposure and decreased fertilisation rates in vitro

The effect of paternal occupational exposures on fertilising ability was investigated in 836 couples who sought in-vitro fertilisation treatment. Fertilisation rates were significantly decreased for couples with paternal pesticide exposure.

General ageing and ovarian ageing

The age related decrease in female fertility is associated with a decrease in follicle numbers and oocyte quality. Meiotic division errors, mitochondrial DNA mutations and ageing itself have been suggested to play a part in the age associated reduction in oocyte quality. During the past decades several hypothesis have been proposed, trying to explain the underlying mechanisms. However, none of them is yet conclusive. This review will consider the main hypotheses regarding the age related reduction in oocyte quality. This will be reviewed together with recent results of studies analysing a possible relationship between ageing and ovarian ageing. On the basis of our own results and those presented in the literature, it is concluded that ovarian ageing may only be related to specific aspects of general ageing.

Retrospective analysis of subcutaneous administration of urinary gonadotrophins in in vitro fertilisation

SummaryThe objective of this study was to assess the clinical efficacy and acceptability of subcutaneous self-injection of urinary gonadotrophins in controlled ovarian hyper-stimulation followed by in vitro fertilisation (IVF). Data on 524 patients, treated during 1276 IVF cycles following either a short or middle-long stimulation protocol using the gonadotrophin-releasing hormone agonist leuprolide, human menopausal gonadotrophin (hMG) and human chorionic gonadotrophin (hCG) subcutaneously, were retrospectively analysed. The 1276 simulation cycles resulted in 1252 ovum-pick-ups, 1015 embryo transfers, and 228 clinical pregnancies, leading to a clinical pregnancy rate/ovum pick-up of 18·2 per cent. Only five patients (< 1 per cent) complained of transient skin reactions at the injection site. It was concluded that the clinical efficacy of subcutaneous administration of hMG and hCG is high, and the reported incidence of side effects is low. The procedure is well-tolerated, is easy to perform both at home a...

Synthesis of a mucous glycoprotein in the human uterus

Scrapings of endometrium and uterine contents of 10 women were analysed. In the uterine lumina of two women that used synthetic progestagens, a considerable amount of mucus was present. We fractionated the mucus by CsCl density equilibrium centrifugation into glycoprotein and protein fractions. With sugar and amino acid analysis the glycoprotein could be classified as a typical epithelial glycoprotein, resembling the cervical glycoprotein. It contains neuraminic acid (6.2%) and sulfate (8.4%). From the uteri of the other 8 women, who did not use hormones, a small amount of a similar glycoprotein could be isolated.