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J H Parsons

Publications and source records attributed to J H Parsons.

25 records · Page 2Linked to original sources
PubMed1985

Clinical evaluation of the heterologous oocyte penetration (HOP) test.

The heterologous oocyte penetration (HOP) test, using zona-free hamster oocytes, was used to assess the fertilising capacity of human spermatozoa. There was good correlation between the ability of ejaculated spermatozoa to penetrate the zona-free hamster oocytes and intact human oocytes. Using epididymal spermatozoa, the HOP test results showed that the ability to penetrate oocytes was acquired during their passage through the epididymis. Applied clinically, the HOP test enables a group of infertile men to be identified with a functional defect of their spermatozoa; these men may not be identified at routine seminal fluid analysis. Men with two negative HOP test results were confirmed as being infertile since their wives, if normal, conceived rapidly when donor spermatozoa were artificially inseminated.

Animals↗
PubMed1984

Serum oestradiol and preovulatory follicular development before in-vitro fertilization.

Twenty-three in-vitro fertilization (IVF) treatment cycles (four unstimulated and 19 clomiphene-stimulated) were assessed retrospectively to discern relationships among serum oestradiol (OE2) titre on the day that human chorionic gonadotrophin (hCG) was given and the number and size of ovulatory follicles available for aspiration of oocytes during laparoscopy 32-38 h after hCG injection. Since 12 of the cycles succeeded to the stage of embryo replacement and two normal term pregnancies resulted, the series as a whole offers a useful referent data base. When only one ovulatory follicle developed (n = 8) the average volume of aspirated follicular fluid was approximately 6 ml, equivalent to a follicular diameter between 22 and 23 mm. When multiple follicles developed (mean 2.7/patient, n = 15), average fluid volume/follicle was not significantly different, averaging approximately 5.5 ml. Serum OE2 titre on the morning before hCG was injected ranged between 0.9 and 5.5 nmol/l and corresponded to the number of follicles aspirated at laparoscopy. There was a highly significant linear correlation (r = 0.85, P less than 0.001) between this OE2 value (X nmol/l) and total aspirated fluid volume (Y ml) where Y = 2.07 + 3.65 X. Thus taking 6 ml as the 'typical' fluid volume, the calibration line and its 95% confidence limits could be used to establish provisional 'ideal' pre-hCG serum OE2 titre ranges corresponding to the development of one, two or three mature ovulatory follicles. This information, combined with a knowledge of the number of presumptive preovulatory follicles present (assessed by ovarian ultrasound), can aid the timing of the hCG injection before IVF.

Adolescent↗
PubMed1979

Maturity of fetal lungs tested by production of stable microbubbles in amniotic fluid.

Lung surfactant in amniotic fluid, and hence the maturity of the fetal lungs, can be assessed by observation of stable microbubbles (less than 15 micron diameter). Bubbles are formed by agitation with a Pasteur pipette and examined in hanging drops under the 10 x power of a microscope. Either after a count of bubbles, or after a general survey of hanging drops, the fluid is given a stable microbubble rating. A 'strong' rating indicates that the idiopathic respiratory distress syndrome will not occur after delivery, and that the lecithin/sphingomyelin ratio will indicate maturity. Complete absence of stable microbubbles suggests a high risk of respiratory trouble for the newborn infant, as does a weak or lower rating in the 30 to 37 week gestational age group. The test takes 5 to 10 minutes to perform, is cheap and easy, is not affected by blood, but may be affected by meconium. If a 'strong' rating is found, measurement of the L/S ratio can safely be omitted.

Amniotic Fluid↗
PubMedDate not supplied

Use of the heterologous ovum penetration test to predict the fertilising capacity of human spermatozoa.

The ability of human spermatozoa to penetrate zona-free hamster ova in a heterologous ovum penetration (HOP) test was compared with the fertilisation of human oocytes in 54 normospermic couples. Concordant results were seen in 45/54 (83%) cases. However, false-positive HOP test results occurred in 5/45 (11%) couples and false-negative results in 4/9 (44%) couples. The data suggest that a positive HOP test result is a good indication that fertilisation will occur, although a negative HOP test result does not necessarily mean that fertilisation will not take place.

Animals↗