### Abstract

Objective: To develop a mathematical formula that accurately predicts the probability of a singleton, twin, and higher-order multiple pregnancy according to implantation rate and number of embryos transferred. Design: A total of 12,003 IVF cycles from a single center resulting in ET were analyzed. Using mathematical modeling we developed a formula, the Combined Formula, and tested for the ability of this formula to accurately predict outcomes. Setting: Academic hospital. Patient(s): Patients undergoing IVF. Intervention(s): None. Main Outcome Measure(s): Goodness of fit of data from our center and previously published data to the Combined Formula and three previous mathematical models. Result(s): The Combined Formula predicted the probability of singleton, twin, and higher-order pregnancies more accurately than three previous formulas (1.4% vs. 2.88%, 4.02%, and 5%, respectively) and accurately predicted outcomes from five previously published studies from other centers. An online applet is provided (https://secure.ivf.org/ivf-calculator.html). Conclusion(s): The probability of pregnancy with singletons, twins, and higher-order multiples according to number of embryos transferred is predictable and not random and can be accurately modeled using the Combined Formula. The embryo itself is the major predictor of pregnancy outcomes, but there is an influence from "barriers," such as the endometrium and collaboration between embryos (embryo-embryo interaction). This model can be used to guide the decision regarding number of embryos to transfer after IVF.

Original language | English (US) |
---|---|

Journal | Fertility and Sterility |

Volume | 98 |

Issue number | 6 |

DOIs | |

State | Published - Dec 2012 |

Externally published | Yes |

### Fingerprint

### Keywords

- embryo transfer
- In vitro fertilization
- mathematical modeling
- multiples
- outcome predictors

### ASJC Scopus subject areas

- Obstetrics and Gynecology
- Reproductive Medicine

### Cite this

*Fertility and Sterility*,

*98*(6). https://doi.org/10.1016/j.fertnstert.2012.08.014

**Reducing multiples : A mathematical formula that accurately predicts rates of singletons, twins, and higher-order multiples in women undergoing in vitro fertilization.** / Williams, Zev; Banks, Eric; Bkassiny, Mario; Jayaweera, Sudharman K.; Elias, Rony; Veeck, Lucinda; Rosenwaks, Zev.

Research output: Contribution to journal › Article

*Fertility and Sterility*, vol. 98, no. 6. https://doi.org/10.1016/j.fertnstert.2012.08.014

}

TY - JOUR

T1 - Reducing multiples

T2 - A mathematical formula that accurately predicts rates of singletons, twins, and higher-order multiples in women undergoing in vitro fertilization

AU - Williams, Zev

AU - Banks, Eric

AU - Bkassiny, Mario

AU - Jayaweera, Sudharman K.

AU - Elias, Rony

AU - Veeck, Lucinda

AU - Rosenwaks, Zev

PY - 2012/12

Y1 - 2012/12

N2 - Objective: To develop a mathematical formula that accurately predicts the probability of a singleton, twin, and higher-order multiple pregnancy according to implantation rate and number of embryos transferred. Design: A total of 12,003 IVF cycles from a single center resulting in ET were analyzed. Using mathematical modeling we developed a formula, the Combined Formula, and tested for the ability of this formula to accurately predict outcomes. Setting: Academic hospital. Patient(s): Patients undergoing IVF. Intervention(s): None. Main Outcome Measure(s): Goodness of fit of data from our center and previously published data to the Combined Formula and three previous mathematical models. Result(s): The Combined Formula predicted the probability of singleton, twin, and higher-order pregnancies more accurately than three previous formulas (1.4% vs. 2.88%, 4.02%, and 5%, respectively) and accurately predicted outcomes from five previously published studies from other centers. An online applet is provided (https://secure.ivf.org/ivf-calculator.html). Conclusion(s): The probability of pregnancy with singletons, twins, and higher-order multiples according to number of embryos transferred is predictable and not random and can be accurately modeled using the Combined Formula. The embryo itself is the major predictor of pregnancy outcomes, but there is an influence from "barriers," such as the endometrium and collaboration between embryos (embryo-embryo interaction). This model can be used to guide the decision regarding number of embryos to transfer after IVF.

AB - Objective: To develop a mathematical formula that accurately predicts the probability of a singleton, twin, and higher-order multiple pregnancy according to implantation rate and number of embryos transferred. Design: A total of 12,003 IVF cycles from a single center resulting in ET were analyzed. Using mathematical modeling we developed a formula, the Combined Formula, and tested for the ability of this formula to accurately predict outcomes. Setting: Academic hospital. Patient(s): Patients undergoing IVF. Intervention(s): None. Main Outcome Measure(s): Goodness of fit of data from our center and previously published data to the Combined Formula and three previous mathematical models. Result(s): The Combined Formula predicted the probability of singleton, twin, and higher-order pregnancies more accurately than three previous formulas (1.4% vs. 2.88%, 4.02%, and 5%, respectively) and accurately predicted outcomes from five previously published studies from other centers. An online applet is provided (https://secure.ivf.org/ivf-calculator.html). Conclusion(s): The probability of pregnancy with singletons, twins, and higher-order multiples according to number of embryos transferred is predictable and not random and can be accurately modeled using the Combined Formula. The embryo itself is the major predictor of pregnancy outcomes, but there is an influence from "barriers," such as the endometrium and collaboration between embryos (embryo-embryo interaction). This model can be used to guide the decision regarding number of embryos to transfer after IVF.

KW - embryo transfer

KW - In vitro fertilization

KW - mathematical modeling

KW - multiples

KW - outcome predictors

UR - http://www.scopus.com/inward/record.url?scp=84870308180&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84870308180&partnerID=8YFLogxK

U2 - 10.1016/j.fertnstert.2012.08.014

DO - 10.1016/j.fertnstert.2012.08.014

M3 - Article

C2 - 22985944

AN - SCOPUS:84870308180

VL - 98

JO - Fertility and Sterility

JF - Fertility and Sterility

SN - 0015-0282

IS - 6

ER -