Despite the label of being "infertile," some couples who have tried fertility treatments are later able to have a baby naturally, according to a new study from France.
In some instances from the research, the parents had had another child previously using in vitro fertilization (IVF) -- while in other cases the couple had a baby even after an unsuccessful experience with IVF.
"Most infertile couples think that they are unable to conceive spontaneously whereas our study shows (this) remains possible," Dr. Pénélope Troude at the French national medical research institute, INSERM, wrote in an email to Reuters Health.
"Our results should give hope to couples who have been unsuccessfully treated by IVF," Troude and her colleagues wrote in their report, published in the journal Fertility and Sterility.
Researchers have previously reported that couples waiting for IVF treatment will occasionally drop off of the wait list because they become pregnant without fertility treatment -- what doctors refer to as a "spontaneous" pregnancy.
To get a better sense of how frequently people going through IVF end up having babies without extra help, Troude and her colleagues collected information on about 2,100 couples who had begun fertility treatment in France in the early 2000s.
About 1,300 of those couples successfully ended up having a baby through IVF.
Eight to 10 years later, the couples responded to a survey about whether they'd had a child on their own following fertility treatment.
Among the parents who'd had a baby through IVF, 17 percent later had another child without assistance. And among couples who originally failed to have a baby with fertility treatment, 24 percent went on to have one from a spontaneous pregnancy.
"It must be borne in mind that infertility did not mean no chance to conceive but low or very low chance to conceive," Troude said.
Dr. Johannes Evers, a professor of obstetrics and gynecology at Maastricht University Medical Center in the Netherlands, said that couples' behavior can explain why people whose IVF didn't work out had a higher rate of natural pregnancies afterward.
"Successful couples already had their child(ren), so they will have used contraception," Evers, who was not involved in the study, wrote in an email to Reuters Health. Men and women who were younger had a better chance of having a baby naturally, as did couples whose infertility didn't have a clear cause.
For instance, among women younger than 35 with unexplained infertility, 45 percent became pregnant after failing to have a baby through IVF.
Infertility can be caused by hormonal problems or low sperm count, for example, but in 12 to 13 percent of couples in the study, the cause was unknown.