Losing excess weight before undergoing in vitro fertilization (IVF) treatment can improve pregnancy and birth outcome, according to a new study.
For the study, a team led by Dr Jose Bellver closely examined 10,000 egg donation treatment cases conducted at three IVF centers in Spain.
Researchers measured and recorded weights and the Body Mass Indices (BMI) of both the egg donors and egg recipients. BMI is a measure based on a person's weight and height, to measure body fat.
While the egg donors were healthy and were of normal weight, recipients had different weights- 1,458 women had a body mass index(BMI) below 20; 5,706 women had a BMI between 20 and 24.9; 1,770 women had a BMI between 25 and 29.9 and 653 women had a BMI above 30.
They found that maternal obesity was interfering with the uterus' ability to adapt to the embryo implantation, thus reducing the overall chances of an IVF success. Chances of successful embryo implantation, pregnancy and live birth came down as the numbers on the weighing scale went up.
The women with normal weight (BMI below 20) had higher live birth rates (38.6 percent) and embryo implantation (40.4 percent) compared to obese women (BMI above 30 -27.7 percent and 30.9 percent respectively).
The findings were presented at the annual meeting of European Society of Human Reproduction and Embryology (ESHRE) last week showing that obesity was lowering rates of implantation by 23 percent, clinical pregnancy by 19 percent and live birth by 27 percent.
This may be a result of obesity affecting "the different components of the reproductive system independently," Dr Bellver said.
"The clinical evidence is now strong enough for implementing preconceptional health policies for obese patients considering assisted reproduction," Dr Bellver, said in a news release. The control of excess weight, especially through lifestyle interventions, should be mandatory not only for improving reproductive and obstetric outcomes, but also for reducing costs derived from the greater consumption of drugs in IVF, failed treatments, maternal and neonatal complications, and metabolic and non-metabolic diseases in the offspring."
A body mass index (BMI) of 19 to 25 is considered to be the ideal weight for conceiving. A healthy body and optimum weight during pregnancy is crucial for having a smooth pregnancy and delivering a healthy child. However, one-third of women of childbearing age and one in five pregnant women in the United States are obese.
