Aimee S. Chang

Morbid obesity is associated with lower clinical pregnancy rates after in vitro fertilization in women with polycystic ovary syndrome

OBJECTIVE To determine whether morbid obesity is associated with decreased pregnancy and live birth rates after IVF in women with polycystic ovary syndrome (PCOS). DESIGN Retrospective cohort study. SETTING University-based fertility center. PATIENT(S) Seventy-two women with PCOS who completed their first IVF cycle between 2001 and 2006. INTERVENTION(S) Outcomes of IVF were compared between women with a body mass index (BMI) of <40 kg/m(2) vs. those with a BMI of > or =40 kg/m(2). MAIN OUTCOME MEASURE(S) Clinical pregnancy rate, live birth rate. RESULT(S) Morbidly obese women with PCOS (n = 19) had significantly lower clinical pregnancy rates after IVF than patients with PCOS who were not morbidly obese (n = 53) (32% vs. 72%, relative risk 0.44, 95% confidence interval 0.22-0.87). Their live birth rates were lower too, although this difference was not statistically significant (32% vs. 60%, relative risk 0.52, 95% confidence interval 0.26-1.05). CONCLUSION(S) Morbid obesity is associated with lower pregnancy rates in women with PCOS after IVF, raising the question of whether weight loss may improve IVF success rates for morbidly obese PCOS patients.

Factors associated with preterm delivery in mothers of children with Beckwith–Wiedemann syndrome: A case cohort study from the BWS registry

Pregnancy that results in a child with Beckwith–Wiedemann syndrome (BWS) is associated with preterm delivery. Based on previous case series, we hypothesized that preterm delivery of a child with BWS was due to known risk factors for preterm delivery such as polyhydramnios and gestational hypertension. A case cohort study using the BWS Registry at Washington University School of Medicine was undertaken. Cases were pregnancies that resulted in the birth of a child with BWS, controls were pregnancies resulting in the birth of siblings without BWS. Univariate analyses of maternal complications and logistic regression to predict preterm delivery were used. Children with BWS (n = 304) were delivered preterm at a significantly higher rate than their siblings (n = 269) odds ratio 19.1 (95% CI 9.1–40.2). Polyhydramnios, gestational hypertension, and vaginal bleeding also occurred at high rates in the BWS group with odds ratios of 31.6 (95% CI 12.6–79.1), 2.4 (95% CI 1.4–4.1), and 3.9 (95% CI 2.3–6.4), respectively. In a multivariate logistic regression model within the BWS group, polyhydramnios, vaginal bleeding, and gestational hypertension were significant predictors of preterm delivery, odds ratios of 2.9 (95% CI 1.6–5.4), 2.6 (95% CI 1.3–5.0), and 5.3 (2.3–12.0), respectively. However, a significant proportion, 6.5% (18 of 277), of patients in the BWS group delivered preterm without known risk factors. Preterm delivery of a child with BWS is associated with an increased frequency of polyhydramnios, gestational hypertension, and vaginal bleeding in the mother. However, preterm delivery also occurs in the absence of these risk factors.

A prospective, randomized, double-blinded study of assisted hatching in women younger than 38 years undergoing in vitro fertilization

OBJECTIVE To determine whether assisted hatching is beneficial to IVF patients younger than 38 years whose embryos have a thickened zona pellucida (ZP). DESIGN Prospective, randomized, double-blinded, crossover study. SETTING University-based infertility center. PATIENT(S) One hundred twenty-one women less than 38 years of age, undergoing IVF at Washington University between April 2004 and February 2007, with ZP thickness > or =13 microm for any embryos. INTERVENTION(S) Measurement of ZP thickness in embryos undergoing IVF; randomization of women with embryos with ZP thickness > or =13 microm to no procedure or assisted hatching performed by acidic Tyrodes solution. MAIN OUTCOME MEASURE(S) Clinical intrauterine pregnancy rate, implantation rate, spontaneous pregnancy loss, and live birth rate. RESULT(S) Baseline characteristics and ZP thickness were not significantly different between the two study arms (hatched and unhatched). No significant differences were observed between hatched and unhatched patients in the rates of clinical pregnancy (47% vs. 50% respectively) or live birth (46% vs. 45% respectively). Further, no significant differences were noted between hatched and unhatched groups in rates of spontaneous abortions, monozygotic twinning, dizygotic twinning, chromosomal abnormalities, or ectopic gestations. In addition, mean ZP thickness did not have a significant effect on pregnancy. CONCLUSION(S) In patients younger than 38 years with embryos with ZP thickness of > or =13 microm, assisted hatching does not improve the rates of implantation, clinical pregnancy, or live birth, and thus does not appear to offer any benefit to patients in this age group undergoing IVF.

Encouraging patient-driven single-embryo transfer

Single-embryo transfer (SET) removes the risk of multiples in in vitro fertilization (IVF), but women with unfavorable IVF prognosis have been dissuaded from SET despite their desire to avoid multiples. In our clinic, 54% of the women who requested SET delivered healthy singletons, even though only two of them had met the American Society for Reproductive Medicines SET guidelines. This demonstrates the value of encouraging patient-driven SET.