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Biomedical subjects

A M Lower

Publications and source records attributed to A M Lower.

28 records · Page 2Linked to original sources
PubMed1998

Effect of smoking on ovarian reserve and ovarian stimulation in in-vitro fertilization and embryo transfer.

The effect of cigarette smoking on ovarian reserve as measured by basal serum follicle stimulating hormone (FSH) concentrations, and by the response to a standard ovarian stimulation protocol, was examined retrospectively in 173 consecutive women (108 non-smokers and 65 smokers) undergoing in-vitro fertilization (IVF) and embryo transfer treatment. Women who smoked had a higher mean basal serum FSH concentration (P < or = 0.0001), in particular younger (<36 years) women, and required a statistically significantly higher mean dosage of gonadotrophins for ovarian stimulation than the non-smokers (48.1 +/- 15.6 versus 38.9 +/- 13.6 ampoules, 75 IU/ampoule; P < 0.0001). A lower mean number of oocytes was obtained in smokers than non-smokers (6.2 +/- 3.4 versus 11.1 +/- 6.3, oocytes P < or = 0.0001) and the rate of abandoned cycles (18.5 versus 8.5%) and total fertilization failure (18.5 versus 8.5%) was higher. The clinical pregnancy rate per cycle in smokers was 16.9% versus 21.3% in non-smokers but this was not statistically significant. In conclusion, cigarette smoking in women appears to significantly reduce their ovarian reserve and lead to poor response to ovarian stimulation at an earlier age.

Adult↗
PubMed1998

Routine use of saline hysterosonography in 500 consecutive, unselected, infertile women.

Saline hysterosonography was attempted as a routine, first-line screening test of uterine structure in 500 consecutive, unselected, infertile women. The procedure was completed in 96.8% (484/500) women and the observations were interpretable in 483 of these women. Intrauterine pathology was suspected in 67/499 (13.4%) women on plain ultrasound scan and 58/484 (12%) women with saline hysterosonography. Ultrasound alone had a superior specificity (96.3%) to sensitivity (81.8%) and better negative (97.6%) than positive (73.8%) predictive value for the detection of any intrauterine abnormality, using saline hysterosonography as the reference procedure. Suspected pathology at saline hysterosonography led to hysteroscopy in 20 women, after a median of 5.7 months (range, 1-14). The overall concordance rate between the two procedures was 65% with lesions suspicious of intrauterine polyps not present at subsequent hysteroscopy on six occasions. Criteria were established to help identify women with potentially self-limiting lesions, in whom a re-scan should be considered before resorting to hysteroscopy. The procedure was well tolerated with no significant complications. Saline hysterosonography appeared to be an acceptable first-line screening procedure for uterine structure which enhanced the predictive power of ultrasound alone for uterine anomalies and provided additional information which was potentially of value when planning operative hysteroscopy.

Adult↗
PubMed1993

Is luteal function maintained by factors other than chorionic gonadotrophin in early pregnancy?

Women with ectopic pregnancy (n = 14) and early embryonic arrest ('blighted ovum') (n = 9) were studied 16 days after conception, at a time when they were asymptomatic and serum concentrations of beta-human chorionic gonadotrophin (HCG) were in the normal range and increasing at an apparently normal rate. Serum progesterone and oestradiol concentrations were compared with those from normal women matched for gestational age and serum beta-HCG concentration whose singleton intra-uterine pregnancies proceeded normally beyond 20 weeks. Mean serum progesterone concentrations were significantly lower in the women with ectopic pregnancies than in matched controls (P < 0.002); however, there was no difference in the serum progesterone concentrations between women with blighted ova and matched controls. Statistically significant differences were not seen in serum oestradiol concentrations between either group and matched controls. Similarly there was no difference in serum progesterone or oestradiol concentrations in 20 women who conceived ectopic pregnancies and 20 women conceiving blighted ovum pregnancies and their matched intra-uterine controls when conception followed ovarian stimulation. The low serum progesterone concentrations seen in ectopic pregnancy suggest that there is a specific and selective deficiency in progesterone synthesis, which implies that factors other than HCG may influence luteal function.

Chorionic Gonadotropin↗
PubMed1992

The value of serum levels of oestradiol, progesterone and beta-human chorionic gonadotrophin in the prediction of early pregnancy loss.

Serial serum levels of oestradiol, progesterone and the beta-subunit of human chorionic gonadotrophin (beta-HCG) had been performed in 674 cycles in women conceiving a singleton pregnancy, either spontaneously or as a result of assisted conception. To determine the value of these estimations in the prediction of early pregnancy loss, frequency distribution curves and receiver operating characteristic curves were derived for the respective hormones measured at weeks 4-7 of gestation and expressed as multiples of the median (MoM) values in pregnancies occurring both with and without ovarian stimulation. A cut-off level of beta-HCG less than 0.5 MoM gave a sensitivity of 68% with an odds ratio of 4.0 at 7 weeks in unstimulated cycles in the prediction of pregnancy failure. A cut-off of 0.8 MoM for progesterone gave a sensitivity of 59% and an odds ratio of 2.8. Prospective hormonal monitoring during the early weeks of gestation may be useful in the prediction of early pregnancy loss and should help to avoid the emergency presentation of some of the complications of early pregnancy, in particular ectopic pregnancy. The limitations imposed by multiple pregnancies and uncertain gestation due to menstrual data may restrict the use of this strategy to specialist fertility centres.

Abortion, Spontaneous↗
PubMed1991

Chromosome abnormalities detected in chorionic villus biopsies of failing pregnancies in a subfertile population.

OBJECTIVE: To determine the range and prevalence of chromosomal abnormalities occurring in failing pregnancies in subfertile women. DESIGN: Prospective biochemical and ultrasound monitoring of all pregnancies conceived between 1988 and 1990 in a subfertile population. SETTING: A single-centre specialist fertility clinic in Perth, Western Australia. SUBJECTS: Tissue from 50 early pregnancy losses was successfully cultured for chromosomal analysis from 46 pregnancies comprising 29 anembryonic pregnancies, 9 miscarriages and 8 ectopic pregnancies. MAIN OUTCOME MEASURES: Impending pregnancy loss was identified at an early stage. Chromosomal analysis was performed on chorionic villi obtained before the diagnosis became clinically evident. RESULTS: Significant chromosomal abnormalities were identified in 54% (14/26) of early pregnancy losses where gamete manipulation was involved and 45% (9/20) of those following spontaneous conception. The most common abnormalities were trisomies (12 pregnancies, mainly trisomy 16), triploidies (3 pregnancies) and monosomy X (3 pregnancies). An excess of female fetuses was noted with only 24% of conceptuses (11/46) bearing a Y chromosome. CONCLUSIONS: The data indicate a similar rate of chromosomal abnormalities underlying pregnancy losses at earlier stages of pregnancy and after infertility treatments as that reported from the general population. Gamete manipulation does not appear to confer a higher rate of chromosomal abnormalities in ensuing pregnancies.

Adult↗