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Featured researches published by Claire Garrett.


Human Reproduction | 2008

Factors affecting low birthweight after assisted reproduction technology: difference between transfer of fresh and cryopreserved embryos suggests an adverse effect of oocyte collection

W. Shih; D.D. Rushford; Harold Bourne; Claire Garrett; John McBain; David L. Healy; H.W.G. Baker

BACKGROUND Data show that differences exist in the birthweight of singletons after frozen embryo transfer (FET) compared with fresh transfer or gamete intra-Fallopian transfer (GIFT). Factors associated with low birthweight (LBW) after assisted reproduction technology (ART) were studied. METHODS Birthweight, distribution of birthweight, z-score, LBW (<2500 g), gestation and percentage preterm (<37 weeks) for singleton births >19 weeks gestation, conceived by ART or non-ART treatments (ovulation induction and artificial insemination) between 1978 and 2005 were analysed for one large Australian clinic. RESULTS For first births, the mean birthweight was significantly (P < 0.005) lower, and LBW and preterm birth more frequent for GIFT (mean = 3133 g, SD = 549, n = 109, LBW = 10.9% and preterm = 10.0%), IVF (3166, 676, 1615, 11.7, 12.5) and ICSI (3206, 697, 1472, 11.5, 11.9) than for FET (3352, 615, 2383, 6.5, 9.2) and non-ART conceptions (3341, 634, 940, 7.1, 8.6). Regression modelling showed ART treatment before 1993 and fresh embryo transfer were negatively related to birthweight after including other covariates: gestation, male sex, parity, birth defects, Caesarean section, perinatal death and socio-economic status. CONCLUSIONS Birthweights were lower and LBW rates higher after GIFT or fresh embryo transfer than after FET. Results for FET were similar to those for non-ART conceptions. This suggests IVF and ICSI laboratory procedures affecting the embryos are not causal but other factors operating in the woman, perhaps associated with oocyte collection itself, which affect endometrial receptivity, implantation or early pregnancy, may be responsible for LBW with ART.


Human Reproduction | 2010

Prevalence and risk factors for obstetric haemorrhage in 6730 singleton births after assisted reproductive technology in Victoria Australia

David L. Healy; Susan Breheny; Jane Halliday; Alice M. Jaques; D.D. Rushford; Claire Garrett; J.M. Talbot; H.W.G. Baker

BACKGROUND Obstetric haemorrhages have been reported to be increased after assisted reproduction technologies (ART) but the mechanisms involved are unclear. METHODS This retrospective cohort study compared the prevalence of antepartum haemorrhage (APH), placenta praevia (PP), placental abruption (PA) and primary post-partum haemorrhage (PPH) in women with singleton births between 1991 and 2004 in Victoria Australia: 6730 after IVF/ICSI, 24 619 from the general population, 779 after gamete intrafallopian transfer (GIFT) and 2167 non-ART conceptions in infertile patients. Risk factors for haemorrhages in the IVF/ICSI group were examined by logistic regression. RESULTS The IVF/ICSI group had more APH: 6.7 versus 3.6% (adjusted OR 2.0; 95% CI 1.8-2.3), PP: 2.6 versus 1.1% (2.3; 1.9-2.9), PA: 0.9 versus 0.4% (2.1; 1.4-3.0) and PPH: 11.1 versus 7.9% (1.3; 1.2-1.4) than the general population. APH, PP and PA were as frequent in the GIFT group as in the IVF/ICSI group, but were less frequent in the non-ART group. Within the IVF/ICSI group, fresh compared with frozen thawed embryo transfers (FET) was associated with more frequent APH (1.5; 1.2-1.8) and PA (2.1; 1.2-3.7) and the odds ratio increased with number of oocytes collected (1.02; 1.00-1.04). Endometriosis patients had more PP (1.7; 1.2-2.4) and PPH (1.3; 1.1-1.6) than those without endometriosis. FET in artificial cycles was associated with increased PPH (1.8; 1.3-2.6) compared with FET in natural cycles. CONCLUSIONS Obstetric haemorrhages are more frequent with singleton births after IVF, ICSI and GIFT. The exploratory analysis of factors in the IVF/ICSI group, showing associations with fresh embryo transfers in stimulated cycles, endometriosis and hormone treatments, suggests that events around the time of implantation may be responsible and that suboptimal endometrial function is the critical mechanism.


Fertility and Sterility | 2010

Adverse obstetric and perinatal outcomes in subfertile women conceiving without assisted reproductive technologies.

Alice M. Jaques; David J. Amor; H.W. Gordon Baker; David L. Healy; Obioha C. Ukoumunne; Sue Breheny; Claire Garrett; Jane Halliday

OBJECTIVE To determine whether adverse perinatal outcomes are increased in subfertile women. DESIGN Cohort study. SETTING Two tertiary assisted reproductive technologies (ART) centers; Victorian births register. PATIENT(S) Records of women who registered with the clinics (1991-2000), but did not have an infant using ART, were linked to the birth register (1991-2004) to identify singleton non-ART births within 5 years of registration (N = 2171). Controls, matched by maternal age and year of infants birth, were selected randomly from birth records (N = 4363). INTERVENTIONS None. MAIN OUTCOME MEASURE(S) Adverse obstetric and perinatal outcomes. RESULT(S) After adjusting for confounders, compared with controls, subfertile women had increased odds of hypertension or preeclampsia (adjusted odds ratio [OR] 1.29, 1.02-1.61), antepartum hemorrhage (adjusted OR 1.41, 1.05-1.89), perinatal death (adjusted OR 2.19, 1.10-4.36), low birth weight (adjusted OR 1.44, 1.11-1.85), preterm birth <37 weeks (adjusted OR 1.32, 1.05-1.67) or <31 weeks (adjusted OR 2.37, 1.35-4.13), and cesarean delivery (adjusted OR 1.56, 1.37-1.77). There was weak evidence for increased birth defects (adjusted OR 1.30, 0.98-1.72) and gestational diabetes (adjusted OR 1.25, 0.96-1.63). No increased risk was found for prelabor rupture of membranes, small for gestational age, or postpartum hemorrhage. CONCLUSION(S) Subfertile women with singleton births are at increased risk of several adverse outcomes. These risks should be considered during their antenatal care and when analyzing adverse effects of ART.


Human Reproduction | 2009

Associations between andrological measures, hormones and semen quality in fertile Australian men: inverse relationship between obesity and sperm output

T.M. Stewart; De Yi Liu; Claire Garrett; Niels Jørgensen; E.H. Brown; H.W.G. Baker

BACKGROUND The World Health Organization developed a time to pregnancy (TTP) study (number of menstrual cycles taken to conceive) to determine whether the average TTP is increasing and semen quality decreasing with time. The present study describes clinical, semen and hormone characteristics obtained from male partners of pregnant women in Melbourne, Australia, and examines the associations between these characteristics. METHODS Male partners (n = 225) of pregnant women (16-32 weeks) who conceived naturally had physical examination, health and lifestyle questionnaires, semen and hormone (FSH, LH, sex hormone-binding globulin, testosterone and Inhibin B) analyses. RESULTS Previously known associations between semen, hormone and clinical variables were confirmed as significant: sperm numbers (concentration and total sperm count) correlated positively with Inhibin B and inversely with FSH and left varicocele, while total testicular volume correlated positively with sperm numbers and Inhibin B and inversely with FSH. However, only abstinence, total testicular volume, varicocele grade and obesity (BMI > 30 kg/m2) were independently significantly related to total sperm count. Compared with those with BMI < 30 (n = 188), obese subjects (n = 35) had significantly lower total sperm count (mean 324 versus 231 million, P = 0.013) and Inhibin B (187 versus 140 pg/ml, P < 0.001) but not FSH (3.4 versus 4.0 IU/l, P = 0.6). CONCLUSIONS Obese fertile men appear to have reduced testicular function. Whether this is cause or effect, i.e. adiposity impairing spermatogenesis or reduced testicular function promoting fat deposition, remains to be determined.


Human Reproduction | 2010

Increased risk of blastogenesis birth defects, arising in the first 4 weeks of pregnancy, after assisted reproductive technologies

Jane Halliday; Obioha C. Ukoumunne; H.W. Gordon Baker; Sue Breheny; Alice M. Jaques; Claire Garrett; David L. Healy; David J. Amor

BACKGROUND The reasons for increased birth defect prevalence following in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are largely unknown. Classification of birth defects by pathology rather than organ system, and examination of the role of embryo freezing and thawing may provide clues to the mechanisms involved. This study aimed to investigate these two factors. METHOD Data on 6946 IVF or ICSI singleton pregnancies were linked to perinatal outcomes obtained from population-based data sets on births and birth defects occurring between 1991 and 2004 in Victoria, Australia. These were compared with 20,838 outcomes for singleton births in the same population, conceived without IVF or ICSI. Birth defects were classified according to pathogenesis. RESULTS Overall, birth defects were increased after IVF or ICSI [adjusted odds ratio (OR) 1.36; 95% CI: 1.19-1.55] relative to controls. There was no strong evidence of risk differences between IVF and ICSI or between fresh and thawed embryo transfer. However, a specific group, blastogenesis birth defects, were markedly increased [adjusted OR 2.80, 95% CI: 1.63-4.81], with the increase relative to the controls being significant for fresh embryo transfer (adjusted OR 3.65; 95% CI: 2.02-6.59) but not for thawed embryo transfer (adjusted OR 1.60; 95% CI: 0.69-3.69). CONCLUSION Our findings suggest that there is a specific risk of blastogenesis birth defects arising very early in pregnancy after IVF or ICSI and that this risk may be lower with use of frozen-thawed embryo transfer.


Contraception | 2000

Efficacy and acceptability of testosterone implants, alone or in combination with a 5α-reductase inhibitor, for male hormonal contraception

Robert I. McLachlan; Jillian McDonald; Debbi Rushford; David M. Robertson; Claire Garrett; H.W. Gordon Baker

Testosterone (T) treatment suppresses serum gonadotropins and reduces sperm output sufficiently for contraceptive efficacy in approximately 70% of Caucasian men. In the remaining 30% of men, an increase in 5alpha-reductase activity may maintain testicular androgen activity, thus accounting for the failure of sperm suppression. The form of T therapy is a major consideration in the safety and acceptability of T-based contraception. As compared to T ester injections, T implants provide a more physiological serum T profile and fewer side effects, but have not yet been used in contraceptive efficacy studies. We have used T implants (800-1200 mg every 3 months) in 29 normal men for 3-16 months. T implants produced long-term suppression of sperm densities below 1 million/mL in approximately 70% of men without significant androgenic side effects. No pregnancies occurred in 214 months of exposure. In 16 men failing to suppress within 3 months of T 800 mg, no evidence of enhanced spermatogenic suppression was seen with the co-administration of the type 2 5alpha-reductase inhibitor, finasteride, for 3 months when compared to placebo. We conclude that: 1) T implants provide adequate spermatogenic suppression in approximately 70% of Caucasian men, a rate comparable to intramuscular T injections but with minimal side effects; and, 2) the inclusion of a type 2 5alpha-reductase inhibitor does not enhance spermatogenic suppression.


Reproductive Biomedicine Online | 2004

Flow cytometry and microscopic acridine orange test: relationship with standard semen analysis.

Anwyn E Apedaile; Claire Garrett; De Yi Liu; Gary N. Clarke; Stephanie A Johnston; H.W. Gordon Baker

Improved prediction of male fertility requires advances in semen analysis. This study examined the reproducibility and independence of the flow cytometry acridine orange test (FCM-AOT) of sperm chromatin integrity as an assessment of semen quality. The study found that FCM-AOT results are not significantly affected by up to 6 h delay in semen preparation (n = 9) or contamination of semen with moderate concentrations of bacteria (<10(8)/ml E. coli or Staph. epidermidis, n = 14). The variation of replicate measurements within samples was low (%Abnormal alpha(t): SD = 1.4, 95%CI = 4.6, n = 25) and different samples from the same men were mostly within the range of measurement error (n = 35). FCM-AOT variables, in particular %Abnormal alpha(t), displayed significant correlations with motility (r = -0.557), vitality (r = -0.469) and morphology (r = -0.464, n = 201), which are similar in magnitude to those existing between the standard semen variables. Surprisingly, no correlation was found between %Abnormal alpha(t) and the microscopic acridine orange test (M-AOT) (n = 185), suggesting the FCM results are sensitive to a different aspect of sperm quality. In summary, this study confirms that although not totally independent of standard semen analysis or the M-AOT, it is found to be a robust, sensitive and reproducible measure of semen quality, representative of the individual.


Human Reproduction | 2009

Recruitment bias in studies of semen and other factors affecting pregnancy rates in fertile men

T.M. Stewart; De Yi Liu; Claire Garrett; E.H. Brown; H.W.G. Baker

BACKGROUND Recruitment bias is possible in population studies of semen quality because few men volunteer. We examine differences between Australian couples with natural conceptions who agreed or declined to participate in such a study. METHODS Women pregnant between 16 and 32 weeks gestation participating in a retrospective time to pregnancy (TTP) study were each requested to recruit their eligible (on the basis of age, place of his birth and of his mothers birth) male partner to complete additional questionnaires, have a physical examination and provide blood and two semen samples. RESULTS From 2061 women who completed the TTP questionnaire (response rate, 98%) there were 928 eligible male partners of whom 225 (24%) were responders. There were significant socio-demographic and self-reported exposure differences between responders and non-responders in particular, female professional occupation, knowledge of the fertile phase, pelvic inflammatory disease, non-smoker at time of conception and wine consumption per week were more frequent in the responders. There was no evidence of a bias for the subfertile being more likely to volunteer for the study. Mean TTP for planned pregnancies for responders and non-responders were 3.3 and 3.8 cycles (P = 0.319), respectively, and the cycle specific pregnancy rates were not significantly different after covariate adjustment by Cox regression. CONCLUSIONS The present study confirms that participation rates are low in studies of semen quality. Although the expected higher participation of subfertile couples was not confirmed, there remains considerable potential for bias and other problems that could invalidate this type of study.


Fertility and Sterility | 2002

Phorbol myristate acetate induces ruffling of the acrosome of human sperm

De Yi Liu; Mirjana Martic; Ivica Grković; Claire Garrett; Marjorie Dunlop; H.W. Gordon Baker

OBJECTIVE To determine the effect of phorbol myristate acetate (PMA) on human acrosome morphology and the acrosome reaction. DESIGN Controlled experiments on sperm and unfertilized oocytes from volunteers. SETTING Academic research and teaching tertiary hospital. PATIENT(S) Sperm samples were from normospermic men and unfertilized oocytes from IVF patients. MAIN OUTCOME MEASURE(S) Acrosome morphology was assessed by using transmission and scanning electron microscopy. The acrosome reaction was assessed by using fluorescein-labeled Pisum sativum agglutinin. RESULT(S) PMA induced acrosome ruffling, indicated by a marked wavy appearance. A significant correlation was found between PMA-induced ruffling and PMA enhancement of the zona pellucida-induced acrosome reaction. Protein kinase C inhibitors bisindolylmalemide I and sangivamycin had no effect on PMA-induced acrosomal ruffling, but actin polymerization inhibitors cytochalasin B and cytochalasin D significantly decreased PMA-induced acrosomal ruffling. In contrast, bisindolylmalemide I, sangivamycin, cytochalasin B, and cytochalasin D significantly decreased both the zona pellucida-induced acrosome reaction and the PMA enhancement of the zona pellucida-induced acrosome reaction. CONCLUSION(S) PMA-induced acrosomal ruffling involves actin polymerization, possibly independent of conventional protein kinase C. Acrosomal ruffling is involved in the PMA augmentation of the zona pellucida-induced acrosome reaction.


Australian & New Zealand Journal of Obstetrics & Gynaecology | 2014

A randomised controlled trial of intra-uterine insemination versus in vitro fertilisation in patients with idiopathic or mild male infertility

Hossam Elzeiny; Claire Garrett; Manuela G. Toledo; Kate Stern; John McBain; Hugh William Gordon Baker

The cause of infertility is unexplained or poorly explained in 30–40% of couples undergoing standard investigations, and treatment ranges from expectant management to IUI and IVF.

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De Yi Liu

University of Melbourne

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Alice M. Jaques

Royal Children's Hospital

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