To assess the impact of embryo biopsy on the reproductive potential of human embryos.

This study will recruit patients from the NY/NJ/CT/eastern PA area only.

All patients will undergo an in vitro fertilization (IVF) cycle with hormonal stimulation and an egg retrieval procedure as deemed appropriate for their diagnosis. Following biopsy, the embryos will be transferred. There will be no delay in the time of transfer as no cells will be analyzed prior to transfer.

On day 3 or day 5 of embryo development, all patients will undergo a two (2) embryo transfer. The embryos selected for transfer will be the 2 morphologically best of the embryo cohort. Once selected for transfer, the embryos will be randomized so that one will be biopsied and the other will be transferred without undergoing biopsy. The embryo randomized to biopsy will have a single cell biopsied.

Following delivery, buccal swabs will be collected from infants.

This study will recruit patients from the NY/NJ/CT/eastern PA area only.

Inclusion Criteria:

1. Maximum of one prior failed IVF treatment cycle
2. Female partner less than 35 years of age
3. Normal day 3 FSH level (<10 miu/mL)
4. Total basal antral follicle count greater than or equal to 12
5. Male partner with greater than 100,000 total motile spermatozoa and at least 1% normal forms
6. Body mass index (BMI) < or = 32
7. Normal uterine cavity

Exclusion Criteria:

1. Diagnosis of chronic anovulation secondary to polycystic ovarian disease
2. Diagnosis of endometrial insufficiency
3. Clinical indication for pre-implantation genetic diagnosis (PGD) (undergoing IVF with PGD to rule out a known genetic defect)
4. Use of testicular aspiration or biopsy procedures to obtain sperm

200 infertile couples undergoing IVF will be enrolled in the study.