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Biomedical subjects

J P van der Merwe

Publications and source records attributed to J P van der Merwe.

At least 19 recordsLinked to original sources
PubMed2003

Factors affecting pregnancy outcome in a gamete intrafallopian transfer (GIFT) programme.

OBJECTIVE: To identify the factors that most significantly affected pregnancy rates in a gamete intrafallopian transfer (GIFT) programme. METHODS: A total of 863 GIFT cycles were analysed retrospectively. The variables found to be associated significantly with pregnancy were then used to obtain multivariate analysis using logistical regression. RESULTS: Overall and ongoing pregnancy rates were significantly better in patients < or = 38 years than in patients > 38 years (37.3% and 28.4% v. 23.7% and 11.0% respectively), and age was positively associated with success after GIFT (odds ratio (OR) 1.87, 95% confidence interval (CI): 1.22-2.85). Metaphase I (MI) oocytes were negatively associated with pregnancy (OR 1.54, 95% CI: 0.28-1.04). The highest pregnancy rates occurred when 3 metaphase II (MII) oocytes were transferred (39.8%, OR 7.51, 95% CI: 1.74-32.42). With regard to sperm morphology, overall pregnancy rates of 25.5% (< or = 4% normal forms) and 37.2% (> 4% normal forms) were obtained. Morphology of > 4% normal forms was positively associated with pregnancy (OR 1.58, 95% CI: 1.04-2.42). CONCLUSION: The results of this study suggest that the most important factors influencing pregnancy rates in a GIFT programme are the woman's age and those factors pertaining to the characteristics of the gametes. Considering the emotional and financial costs it is important to relate this information to all prospective participants in a GIFT programme.

Adult↗
PubMed2002

Intracytoplasmic sperm injection with testicular spermatozoa in men with azoospermia.

PURPOSE: The aim of the study was to gain an insight into the optimal management of the infertile couple with the husband suffering from azoospermia. METHODS: One hundred and forty-two intracytoplasmic sperm injection (ICSI) cycles performed with testicular extracted spermatozoa were retrospectively analysed. The following factors were investigated for their possible influence on fertilization, cleavage, damage, pregnancy, and ongoing pregnancy rates: the use of fresh, cryopreserved, and preincubated (24 h) spermatozoa and the etiology of the husbands' azoospermia (obstructive and nonobstructive). All microinjections were performed with apparently normal spermatozoa--a head with a tail of normal length. In 116 cycles at least two embryos were available for transfer. RESULTS: The overall fertilization, clinical pregnancy, and ongoing pregnancy rates obtained for the 116 cycles were 65.0, 30.2, and 22.4% respectively. Similar outcomes were obtained for cycles using fresh testicular and cryopreserved testicular spermatozoa. Similarly, no significant differences were obtained between the cycles using spermatozoa from obstructive or nonobstructive azoospermic patients. An increase in motility after a 24-h preincubation was observed, and although this group was relatively small (n = 17), a significant improvement in fertilization (73.7%) and pregnancy (53.9%) rate was obtained when the testicular sample was preincubated for 24 h. This improvement prevailed in the obstructive azoospermic group, but was less pronounced in nonobstructive patients. CONCLUSIONS: This study shows that the outcome of fresh and frozen-thawed testicular spermatozoa in ICSI is comparable, obstructive and nonobstructive etiologies perform the same, and that preincubation of testicular spermatozoa results in increased fertilization and pregnancy rates. All testicular biopsies are therefore performed the day before oocyte retrieval, superfluous spermatozoa cryopreserved, and the remaining testicular homogenate preincubated for the 24 h prior to oocyte retrieval. With this regime, most azoospermic patients are treated successfully, irrespective of the use of fresh or frozen-thawed spermatozoa from obstructive or nonobstructive cases.

Cryopreservation↗
PubMed1994

Fertilization efficiency of morphologically abnormal spermatozoa in assisted reproduction is further impaired by antisperm antibodies on the male partner's sperm.

OBJECTIVE: To investigate the influence of antisperm antibodies on the sperm surface on the outcome of IVF and GIFT. DESIGN: Matched controlled retrospective review of two large series. SETTING: Reproductive endocrine divisions of two level-three academic centers. PATIENTS: Twenty-nine male factor patients (38 IVF cycles) showing positive antisperm antibodies on the sperm by immunobead test treated by IVF at the Norfolk program and 56 similar patients (57 cycles) treated by GIFT at the Tygerberg program. Twenty-nine male factor patients (29 IVF cycles) with negative antisperm antibodies screening matched by wife's stimulation protocol and baseline semen analysis characteristics were used as controls in Norfolk; 56 GIFT patients (56 GIFT cycles) matched similarly were the Tygerberg controls. Study and control groups were divided according to sperm morphology pattern in normal, good, and poor prognosis subgroups for comparison. MAIN OUTCOME MEASURES: Fertilization rate of preovulatory oocytes used in IVF in Norfolk and of GIFT supernumerary preovulatory oocytes in Tygerberg; total and term pregnancy rates (PRs) and abortion rates. RESULTS: Fertilization rate was significantly lower in the IVF (41.9% +/- 2.8%) as well as in the GIFT (26.8% +/- 3.8%) (mean +/- SE) study groups than in the respective control groups (73.1% +/- 3.9% and 61.8% +/- 3.9%). Total and term PRs in IVF per cycle (21.1% +/- 6.6%; 13.2% +/- 5.5%) and per transfer (23.5% +/- 7.4%; 14.7% +/- 6.1%), and in GIFT (25.0% +/- 5.8%; 19.6% +/- 5.3%) in the study groups were also lower when compared with their control counterparts (IVF per cycle: 62.1% +/- 6.2% and 41.4% +/- 6.0%; IVF per transfer: 41.9% +/- 2.0% and 27.9% +/- 1.9%; GIFT: 31.6% +/- 6.2% and 28.1% +/- 6.0%), but the difference did not reach statistical significance. Abortion rates were similar in the IVF study group (37.5% +/- 17.1%) and its control groups (39.9% +/- 11.5%). The abortion rate in the GIFT study group was 14.3% +/- 9.4%, and no abortions were recorded in the control group (not significant). CONCLUSIONS: The presence of antisperm antibodies on the sperm surface per se impairs the outcome of assisted reproduction, mainly in terms of fertilization rate of preovulatory oocytes, and possibly in terms of total and term PRs. This holds true regardless of the impact of other semen parameters, particularly the morphology of the sperm within the semen sample.

Abortion, Spontaneous↗
PubMed1993

The importance of thyroid microsomal antibodies in the development of elevated serum TSH in middle-aged women: associations with serum lipids.

OBJECTIVE: We assessed the relative risk of both serum TSH and antithyroid antibody concentrations with regard to progression of thyroid failure and studied the lipid profiles of individuals with elevated TSH levels. DESIGN, PATIENTS AND MEASUREMENTS: In a randomly selected group of 427 women aged 40-60 (mean 55) years volunteering in an epidemiological survey in Zoetermeer, TSH and thyroid microsomal antibodies (TMA) were determined. Ten years after the initial survey only TSH was measured and the lipid profiles of the individuals with elevated serum TSH levels were studied and compared with a reference group. RESULTS: During follow-up, four of 427 women were treated with thyroxine. Seventeen of 423 women initially had elevated serum concentrations of TSH (> 4.2 mU/l), 11 of whom were TMA positive. In the group of 406 women with initially a normal TSH, nine out of 37 (24%) TMA-positive women developed elevated serum levels of TSH over 10 years. In contrast only 10 of 369 (3%) TMA-negative women had elevated serum TSH levels 10 years after the initial survey (P < 0.001). Altogether, at the end of the observation period, 40% of TMA-positive subjects had elevated serum TSH concentrations, compared to 3% in the TMA-negative group (P < 0.01). TSH levels in the upper part of the normal range also appeared to have a predictive value: if those both with TSH levels between 2.0 and 4.2 and with a positive TMA status were contrasted with those without antibodies and low TSH, the crude relative risk was 71.5 (31.0-164.3), whereas the crude relative risk of presence versus absence of TMA was only 36.3 (18.8-70.3). Women with elevated TSH levels did not show changes in serum concentrations of total cholesterol (7.4 +/- 1.1 mmol/l), apo-A, (4.7 +/- 1.0 mmol/l) and apo-B (3.1 +/- 0.7 mmol/l) lipoproteins, compared with control individuals (7.2 +/- 1.3, 4.7 +/- 0.8 and 3.0 +/- 0.7 mmol/l, respectively). CONCLUSIONS: The determination of serum TMA in middle-aged women can identify an important group of women at risk of developing an elevated serum TSH. TMA measurement is of potential use in the prevention of cardiovascular disease. An elevated serum TSH, however, in our study-group does not seem to be accompanied by an abnormal lipid profile, as reported by others.

Adult↗
PubMed1992

The role of oocyte maturity in the treatment of infertility because of teratozoospermia and normozoospermia with gamete intrafallopian transfer.

OBJECTIVE: To determine the effect of oocyte maturity on pregnancy rate (PR) in patients undergoing gamete intrafallopian transfer (GIFT) procedures for infertility and in whom male partners had either normozoospermia or teratozoospermia. DESIGN: A prospective study using a combination of clomiphene citrate and human menopausal gonadotropin for ovulation induction was carried out. Five hundred thirty-seven GIFT treatment cycles were analyzed, and 423 cycles yielded four or more oocytes. Patients were divided into two groups according to the sperm morphology: those with less than 14% normal forms and those with greater than 14% normal morphology (as judged by strict criteria). These two groups were divided into a further five subcategories depending on the number of metaphase II oocytes transferred. RESULTS: In the group less than 14% normal forms (category I; 4 metaphase I oocytes replaced), three pregnancies resulted from 33 cycles (9.09%), and in category V (4 metaphase II oocytes transferred) the PR was 15% (14/95) per cycle. In the group with greater than 14% normal forms, in category I, the PR was 16% (3/19) per cycle, and in category V, the PR was 33% (20/61) per cycle. The effect of morphology (less than 14% normal forms versus greater than 14% normal forms) on pregnancy outcome is significant (P = 0.0161). The overall effect of increasing the number of metaphase II oocytes on the pregnancy outcome was not significant (P = 0.1098). However, in the group with greater than 14% normal forms, there was a significant improvement in PR (P = 0.04) in category V. CONCLUSION: During this prospective study, it was shown that sperm morphology plays a significant role in the pregnancy outcome in a GIFT program.

Female↗
PubMed1990

Genital tuberculosis associated with female infertility in the western Cape.

Infertility is a common presenting symptom in women with genital tuberculosis. A study was undertaken to determine the prevalence and characteristics of this disease among the infertile patients (A and B income group) attending the Reproductive Biology Unit at Tygerberg Hospital. Between June 1986 and December 1987, the menstrual fluid from 451 infertile women was cultured for Mycobacterium tuberculosis using Löwenstein-Jensen medium. A prevalence of 7.98% (36/451) was found. Laparoscopic examination of the pelvis revealed bilateral tubal occlusion in 3 patients (8.3%); peritubular adhesions were present in 17 patients (47.2%). In the remaining 16 patients (44.5%), the pelvis was considered normal. No culture-positive patient gave a history of previous infection or contact with tuberculosis. Radiography of the chest and histological examination of the endometrium showed no evidence of infection. Of the 34 patients treated, 13 (38.2%) became pregnant after antituberculosis treatment was completed. If tuberculosis occurs in a population, menstrual fluid of infertile women should be cultured routinely for M. tuberculosis, especially if there is evidence of tubal damage.

Adolescent↗
PubMed1990

Treatment of male sperm autoimmunity by using the gamete intrafallopian transfer procedure with washed spermatozoa.

Sixteen couples were diagnosed as having immunological infertility. To detect sperm-bound immunoglobulin (Ig), i.e., IgA, IgG, and IgM antibodies, the direct immunobead test (IBT) was used. In each individual patient, the direct IBT was greater than or equal to 70% positive for either IgA or IgG or both. The indirect IBT was positive for IgA and IgG antibodies in the serum of all the patients. Semen was collected in 15 mL medium (Ham's F10 [Gibco, Grand Island, NY] + 10% whole blood serum) and prepared with the wash and swim-up method. Patients in the study group were treated for their immunological infertility problem by performing the gamete intrafallopian transfer (GIFT) procedure. An ongoing pregnancy was achieved in 7 of the 16 (43%) couples treated with the GIFT procedure with an ongoing pregnancy rate of 24.1% (7 of 29) per cycle. The GIFT procedure appears to be an effective and safe way of treating male immunological infertility.

Autoantibodies↗
PubMed1990

Gamete intrafallopian transfer as treatment for infertility associated with endometriosis.

Forty-six patients with endometriosis-associated infertility underwent 59 GIFT cycles. The pregnancy rate per cycle was 30.5%. The presence of endometriomas in 11 patients did not affect this rate adversely. We conclude that, provided at least one fallopian tube is patent, GIFT compensates effectively for the possible causes of infertility in these patients.

Adult↗
PubMed1989

Human pregnancy after transfer of intact frozen-thawed embryos.

Since the birth of the first baby as a result of in vitro fertilisation (IVF) in 1978, many clinics around the world have achieved pregnancies and births for their patients by using IVF and gamete intrafallopian transfer procedures. With the storage of excess embryos, multiple laparoscopies can be avoided; this has favoured the development of better cryopreservation techniques. In our clinic 8-cell human embryos are frozen in a 1.5M dimethyl sulphoxide solution as cryoprotectant using the slow freeze-thaw method. Sixteen thawed embryos were replaced in 8 patients, resulting in 1 pregnancy. Of the thawed embryos 51.6% survived the freezing process in that they had 50% or more of the original number of blastomeres and also the zona pellucida intact.

Cryopreservation↗
PubMed1989

Effect of rapid dilution of semen on sperm-bound autoantibodies.

The effect of rapid dilution of autoantibody-positive semen on sperm-bound antibodies was studied in 12 male patients (0-100% IgA and 10-100% IgG). The direct immunobead test (IBT) and the sperm cervical mucus contact (SCMC) test were used to detect sperm-bound antibodies on spermatozoa before and after rapid dilution and swim up in HAM F-10 + 10% human blood serum. All patients tested had normal semen parameters. Sperm-bound antibodies detected after swim-up of semen samples ejaculated into 15 ml HAM F-10 + 10% serum (diluted) did not differ significantly from undiluted samples. Most values were lower (IBT and SCMC) but were not statistically significant. Sperm motility, forward progression, and morphology were statistically improved. Pregnancies resulting from washed semen (diluted) in combination with artificial insemination (AIH) or gamete intrafallopian tube transfer (GIFT) took place in spite of antibodies still present on the sperm membrane and can probably be attributed to improved semen quality, minimizing of ovum-sperm distance, and cervical mucus elimination.

Autoantibodies↗
PubMed1988

Severe ovarian hyperstimulation after follicular aspiration.

In order to maximise the chances of pregnancy, most successful in vitro fertilisation programmes use a combination of ovulation induction agents. This treatment can lead to the hyperstimulation syndrome. Aspiration of the follicles is believed to avoid this syndrome. Despite this approach, hyperstimulation syndrome may still develop. The clinical picture and treatment of a patient with severe hyperstimulation is discussed.

Adult↗
PubMed1987

[Artificial intrauterine insemination with washed prepared spermatozoa of the husband].

Intra-uterine insemination with washed spermatozoa of the husband was evaluated in 42 infertile couples during 103 treatment cycles. A pregnancy rate of 47.3% was obtained after an average of 2 treatment cycles in a group of patients in whom hostile cervical mucus was the only known cause of infertility. A pregnancy rate of 21.7% was obtained after an average of 2.6 treatment cycles in a group of patients in whom low sperm morphology was the only known cause of infertility. The overall conception rate of 33.3% compares favourably with that in other published series.

Female↗
PubMed1987

[Ovulation induction for in vitro fertilisation at the Tygerberg Hospital].

The protocol for in vitro fertilisation (IVF) at Tygerberg Hospital is presented and the results are analysed. Indications for ovulation induction for IVF included the following: (a) irreversible tubal damage; (b) infertility due to immunological factors; (c) male factor-infertility; and (d) endometriosis. A combination of human menopausal gonadotrophin (HMG) and clomiphene citrate (Clomid; Mer-National) and human chorionic gonadotrophin was used. Clomid is given in dosages of 100 mg for 5 days depending on the cycle length. Three doses of HMG (150 IU) are given on alternate days, starting on the second day of clomiphene treatment. If the leading follicle has not reached a mean diameter of 14 mm the day after the last HMG dose, another dose is given. This dosage is continued until the leading follicle reaches a diameter of 14 mm. A total of 109 cycles in 100 patients was analysed. Ova were considered to be mature as soon as the dominant follicle had reached a sonographic average diameter of 18 mm, another two follicles of 16 mm average diameter being present. Serum luteinising hormone levels were determined 4-hourly from the stage when the leading follicles exceeded an average diameter of 14 mm. In this study the pregnancy rate was 21,3% per laparoscopy and 24,4% per embryo transfer. The oestradiol levels on the 5th day of treatment have a predictive value of the length of stimulation.

Adult↗