BMI and fertility

[Guest guest]

Hi All,

BMI and fertility analysis found that the patients with the lowest

BMI,

18.9, had the greatest clinical pregnancy rate for their sperm.

Wow.

The pdf is available.

Fertility and Sterility

Influence of body mass index (BMI) on the outcome of 6,827 IVF cycles

Pages S38-S39

D.A. Ryley, S.R. Bayer, J. Eaton, A. Zimon, S. Klipstein and R.

Reindollar

Influence of body mass index (BMI) on the outcome of 6,827 IVF cycles.

OBJECTIVE: Previous studies have noted that extremes of BMI confer to

the IVF patient significant reductions in both implantation and

pregnancy

rates. A 60% differential in pregnancy rate between very obese (BMI =

35

kg/m 2 ) IVF patients and IVF patients with a moderate BMI (BMI =

20–24.9 kg/m 2 ) has been observed, even when controlling for factors

known to affect the outcome of ART. A similar reduction in pregnancy

rate

of 50% has also been observed between underweight (BMI < 20 kg/m 2 )

IVF patients and those with a moderate BMI. Despite these analyses,

additional studies have failed to note differences in pregnancy rates

among

these groups of patients. The aim of our study was to utilize our

large

IVF-ET database to further define the relationship between IVF

success and

extremes of BMI.

DESIGN: Retrospective.

MATERIALS AND METHODS: We reviewed 6,827 fresh non-donor

IVF cycles at Boston IVF in which the BMI had been recorded. Patients

at

Boston IVF with a BMI > 40 kg/m 2 are not allowed to cycle. Cycles

were

divided among 5 BMI groups: I: <20 kg/m 2 , II: 20–24.9 kg/m 2 , III:

25.0 –29.9 kg/m 2 , IV: 30–34.9 kg/ m 2 , and V: = 35 kg/m 2 .

Characteristics

of the cycles were compared. Differences among the groups were

evaluated

by one-way ANOVA using BMI as the classification variable. The chi

square test was used to determine if there was an association between

BMI

and clinical pregnancy.

RESULTS: 980 (14.4%) cycles were cancelled prior to hCG injection. In

the 5,847 non-cancelled cycles there was no significant difference

with

respect to the number of mature follicles, number of oocytes

retrieved,

number of mature oocytes, cycle number per patient, and number of em-

bryos

transferred among the BMI groups (Table 1). The mean age was

significantly lower among cycles in BMI group V (35.17 years) compared

to all other BMI groups (p<0.0001)a . The mean peak estradiol (pE2)

was

significantly higher in BMI group I (1423.9 pg/ml) compared to the

three

highest BMI groups (p<0.0001)b . A BMI of > 35 kg/m 2 (V) was

associated

with a significantly lower implantation rate (13%, p< .0001)c and

clinical

pregnancy rate (21.75%, p<.0001)d compared to all other BMI groups.

Despite a trend toward lower implantation and pregnancy rates with in-

creasing

BMI, the rates among the 4 lowest BMI groups were not signifi-cantly

different. Table 1. Characteristics of IVF cycles by BMI group. Mean

values are shown unless otherwise specified.

CONCLUSION: A retrospective analysis of 6,827 IVF cycles determined

that severe obesity, defined as a BMI = 35 kg/m 2 , is associated

statistically significant reductions in implantation and clinical

pregnancy

rates. In contrast to other studies, the patients with the lowest BMI

[18.9] had

highest success rates. The efforts of clinicians to optimize patient

weight

profiles prior to IVF are supported by this analysis.

Supported by: None

Cheers, Al Pater.