PubMed Health⌕ Search

Biomedical subjects

P Rainsbury

Publications and source records attributed to P Rainsbury.

5 recordsLinked to original sources
PubMed1993

Excess concepti compared with number of embryos transferred in in vitro fertilization.

To reduce the risk of multiple pregnancy, most in vitro fertilization programs limit the number of embryos transferred; because monozygotic twinning may occur, it is possible that more concepti are produced than the number of embryos transferred. To quantify the prevalence of this phenomenon, 1820 clinical pregnancies generated from 11,601 in vitro fertilization treatment cycles were reviewed. Two patients conceived four fetuses each after having had three embryos transferred, while one conceived three fetuses after having had two embryos transferred. The overall prevalence rate was, therefore, one in 607 cases. The obstetric details of these three pregnancies are reported.

Journal Article↗
PubMed1993

Pregnancy using spermatozoa aspirated from the vas deferens in a patient with ejaculatory failure due to spinal injury.

Aspiration of the vas deferens under local anaesthesia was carried out in a man with ejaculatory failure due to tetraplegia after rectal electrostimulation had failed to provide an ejaculate satisfactory for use in in-vitro fertilization. After passage through a discontinuous Percoll gradient and exposure to 3 mmol pentoxifylline and 3 mmol 2-deoxyadenosine, the final preparation consisted of 50,000 spermatozoa with 4% progressive motility. This was sufficient for the insemination of seven of the 23 oocytes that were collected from the patient's wife by transvaginal ultrasound-guided follicular aspiration. Three high-grade embryos were produced which were transferred transcervically into the uterus 2 days later. A singleton pregnancy resulted which is currently ongoing at 30 weeks gestation. Aspiration of the vas deferens is a relatively simple technique which provides an acceptable alternative to rectal electrostimulation, artificial sperm reservoirs and donor insemination in patients with ejaculatory failure.

Adult↗
PubMed1991

Replacement of frozen-thawed embryos in artificial and natural cycles: a prospective semi-randomized study.

This prospective partly-randomized study assessed the relative efficacy of two strategies of patient management for the replacement of frozen-thawed embryos. A luteinizing hormone-releasing hormone (LHRH) agonist was used to induce a temporary hypogonadism in a group of patients who were then prepared for implantation by endometrial priming with hormone replacement therapy (HRT): oral oestradiol valerate and then oestradiol valerate and injections of progesterone. A second group of patients had their frozen-thawed embryos replaced during their natural cycles. Of the 84 patients treated with the LHRH regimen, 80 had embryos replaced and 16 (20%) clinical pregnancies were established. Of the 78 patients treated with natural cycles, 70 had embryos replaced and 14 (20%) achieved clinical pregnancies. There were no statistical differences between the two groups in terms of age, obstetric history, duration of infertility, number of oocytes retrieved and fertilized or the number of embryos frozen following ovarian stimulation in the embryo 'generating' cycle. In terms of pregnancy rates, both protocols were equally effective. However, the LHRH-HRT protocol was of great value in the management of oligomenorrhoeic patients and in establishing standard conditions for implantation in cyclic patients.

Cryopreservation↗
PubMed1991

Perinatal outcome and congenital malformations in in-vitro fertilization babies from the Bourn-Hallam group.

The perinatal outcome and congenital malformations in children born between 1978 and 1987 in Great Britain after in-vitro fertilization (IVF) at Bourn Hall Clinic and the Hallam Medical Centre are presented. The average maternal age was 34.2 years. Multiple births were frequent, constituting 23% of all deliveries; 19% were twins and 4% triplets. There were no quadruplet or higher order multiple births during that period. Twenty-five per cent of all deliveries were preterm. The mean birth weight was 2793 g and was strongly related to multiplicity of pregnancy and gestational age. Overall, 32% of babies had a low birthweight (less than 2500 g) with 6% having a very low birthweight (less than 1500 g). The overall stillbirth and infant mortality rates were two to three times higher than those of infants born after natural conception in England and Wales; this is attributed to the high incidence of multiple births. The stillbirth rates were 5.07, 20.8 and 24.7 per thousand total births in singletons, twins and triplets respectively. The corresponding figures for perinatal mortality were 13.5, 38.2 and 37 per thousand. Overall, 2.5% of the babies had one or more major congenital malformations diagnosed within one week of life. This was within the range of expected values in the United Kingdom and there was no significant increase in any specific malformation.

Adult↗