Publications by authors named "Thinus Kruger"

Background: Clinical ultrasound is commonly used in medical practices worldwide due to the multiple benefits the modality offers clinicians. Rigorous credentialing standards are necessary to safeguard patients against operator errors. The purpose of the study was to establish and analyse the barriers that specifically lead to poor credentialing success within a resource-limited clinical ultrasound training programme.

View Article and Find Full Text PDF

The shortage of healthcare workers and doctors in the developing world compared with the developed world is problematic, and will continue to be so owing to the ongoing migration of qualified professionals and the inability of the state to remedy the shortfalls. This will seriously hamper the government's National Health Insurance plan and the sustainability of South Africa (SA)'s healthcare sector. Furthermore, it is well known that the duration of medical training in SA is exceptionally long, which discourages trainees.

View Article and Find Full Text PDF

Varicocele is present in approximately 15% of men, and, although it is the most commonly diagnosed cause of male infertility, nearly two-thirds of men with varicoceles remain fertile. It was decided to make use of the current evidence obtained from the previous meta-analyses between 2004 and 2015 as well as available articles covering this field, preferably randomized controlled articles dealing with the topic of semen analysis before and after repair. Two important meta-analyses were discussed as well as other articles dealing with the topic of semen analysis before and after varicocelectomy.

View Article and Find Full Text PDF

Many variables may influence success rates after intrauterine insemination (IUI), including sperm quality in the native and washed semen sample. A literature search was performed to investigate the threshold levels of sperm parameters above which IUI pregnancy outcome is significantly improved and/or the cut-off values reaching substantial discriminative performance in an IUI programme. A search of MEDLINE, EMBASE and Cochrane Library revealed a total of 983 papers.

View Article and Find Full Text PDF

Objective: To compare the efficacy of mild ovarian stimulation versus conventional stimulation in in vitro fertilization (IVF).

Design: Meta-analysis.

Search Strategy: A systemic literature search was carried out for prospective randomised clinical trials.

View Article and Find Full Text PDF

Objective: To determine whether the presence of soluble human leukocyte antigen G (sHLA-G) affects implantation and pregnancy outcomes in vitro.

Design: A multicenter retrospective study.

Setting: Six certified in vitro fertilization (IVF) units.

View Article and Find Full Text PDF

The aim of this study was to investigate the relationship between seminal leukocytes, reactive oxygen species (ROS) production in the ejaculate, and markers of apoptosis in human spermatozoa. Semen samples were collected from 60 patients attending fertility clinics at the Reproductive Biology Unit at Tygerberg Academic Hospital and Vincent Pallotti Hospital, Cape Town, South Africa. The concentration of seminal leukocytes was determined and was correlated with ROS production in the ejaculate, the percentage of superoxide (·O2(-))- and hydrogen peroxide (H2O2)-positive spermatozoa, glutathione activation in the ejaculate, and with markers of apoptosis in spermatozoa, namely cysteine-dependent aspartate-directed proteases (caspase)-3/7 activation, mitochondrial membrane potential (ΔΨm), and the percentage of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL)-positive sperm.

View Article and Find Full Text PDF

Background: The importance of oocyte/embryo ploidy to achieve implantation and a subsequent pregnancy.

Aim: To correlate first and second polar bodies and day-3 blastomere ploidy, embryo morphology and biochemical (sHLA-G) characteristics with blastocyst development and in vitro pregnancy outcome.

Materials And Methods: All oocytes/zygotes and embryos were individually cultured to the blastocyst stage.

View Article and Find Full Text PDF

Objective: We present the first report from the South African Register of Assisted Reproductive Techniques.

Methods: All assisted reproductive technology (ART) centres in South Africa were invited to join the register. Participant centres voluntarily submitted information from 2009 on the number of ART cycles, embryo transfers, clinical pregnancies, age of female partners or egg donors, and use of fertilisation techniques.

View Article and Find Full Text PDF

Objectives: To determine whether clomiphene citrate (CC) can be implicated as a cause for central retinal vein occlusion (CRVO) and other visual disturbances.

Methods: For this systematic review, we performed a search of the following databases: PubMed (1976 to November 2009), Medline Plus 2009, Cochrane Library (1996 to November 2009), Google and Google Scholar (1996 to November 2009). Thirty-five relevant titles (25 full papers and 10 abstracts) were identified and read by authors.

View Article and Find Full Text PDF

Objective: To evaluate the immediate effect of hands-on training on the quality of technical skills of laboratory technicians.

Design: Retrospective analytical study.

Setting: Academic institutions and private infertility clinics.

View Article and Find Full Text PDF

Purpose: To compare pregnancy and implantation rates when embryos are selected based on a single Day 3 (D 3) morphology score vs. a GES score plus sHLA-G expression.

Methods: A prospective randomized study (n = 214) undergoing fresh ICSI cycles.

View Article and Find Full Text PDF

Background: Semen quality is taken as a surrogate measure of male fecundity in clinical andrology, male fertility, reproductive toxicology, epidemiology and pregnancy risk assessments. Reference intervals for values of semen parameters from a fertile population could provide data from which prognosis of fertility or diagnosis of infertility can be extrapolated.

Methods: Semen samples from over 4500 men in 14 countries on four continents were obtained from retrospective and prospective analyses on fertile men, men of unknown fertility status and men selected as normozoospermic.

View Article and Find Full Text PDF

During spermiogenesis, a plasma membrane remodelling step facilitates formation of sperm zona pellucida and hyaluronic acid (HA) binding sites. Enrichment of Tygerberg normal spermatozoa in HA-bound versus semen sperm fractions was postulated. Semen was placed on the uncoated A side and HA-coated B side of a semen chamber.

View Article and Find Full Text PDF

Objective: To establish fertile and subfertile groups of males in couples presenting with endometriosis-related infertility in the female.

Design: Retrospective study of semen profiles on partners of women undergoing surgery for endometriosis-related infertility.

Setting: University-affiliated assisted reproduction center.

View Article and Find Full Text PDF

Objective: The aim of this literature search is to establish if metformin is efficacious when given to clomiphene citrate (CC)-resistant polycystic ovary syndrome (PCOS) patients.

Design: Medline database was searched from 1 January 1980 to 1 January 2005. Inclusion criteria were prospective randomized control trials where metformin was randomized either with placebo or CC to induce ovulation in the CC-resistant patient.

View Article and Find Full Text PDF

Objective: This study aimed to establish the benefit of laser micromanipulation of the zona pellucida as a method of assisted hatching and to determine the optimal technical settings.

Design: Prospective pilot study.

Setting: University teaching hospital.

View Article and Find Full Text PDF

Objective: To report an extremely rare case of endotoxic shock due to Enterobacter cloacae that occurred after laparoscopy for gamete intrafallopian transfer (GIFT) in a nulligravid woman.

Design: Private fertility center in Cape Town, South Africa.

Setting: Case report.

View Article and Find Full Text PDF

Objective: To determine if luteal phase support improves the pregnancy rate in in vitro fertilization (IVF) cycles.

Design: A meta-analysis of randomized trials of luteal phase support was carried out with the main outcome measure being the pregnancy rate per cycle.

Results: Fifty-nine trials were evaluated.

View Article and Find Full Text PDF

Objective: To investigate whether there is an impact of different sources of reactive oxygen species (ROS) on sperm functions.

Design: Prospective study.

Setting: Patients at the Center for Dermatology and Andrology, Giessen, Germany.

View Article and Find Full Text PDF

Objective: To investigate sperm DNA damage in relation to fertilization and pregnancy.

Design: Prospective study.

Setting: The Institute of Reproductive Medicine, Giessen, Germany.

View Article and Find Full Text PDF

Despite the ever-increasing knowledge of the fertilization process, there is still a need for better understanding of the causes of sperm DNA fragmentation and its impact on fertilization and pregnancy. For this reason, human sperm DNA fragmentation was investigated by means of the terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling (TUNEL) assay and the production of reactive oxygen species (ROS) in the ejaculate and in the spermatozoa themselves. These data were correlated with fertilization and pregnancy data from IVF and intracytoplasmic sperm injection (ICSI) patients.

View Article and Find Full Text PDF