Some "infertile" couples who have unsuccessfully tried fertility treatments are later able to have a baby naturally, and a new study from France looks a bit more closely at that phenomenon.
"Most infertile couples think that they are unable to conceive spontaneously whereas our study shows (this) remains possible," Dr Penelope Troude at the French national medical research institute, INSERM, said.
"Our results should give hope to couples who have been unsuccessfully treated by in vitro fertilisation (IVF)," Dr Troude and her colleagues wrote in Fertility and Sterility.
Still, it would be difficult to use the new findings to determine which couples might benefit from a wait-and-see approach, and which couples should proceed with IVF, Dr Troude said.
Hope for couples wanting a baby
And although the findings offer some hope for couples trying to have a baby, she said the long follow-up time in the study and relatively low pregnancy rates "correspond to a very low conception probability."
Researchers have previously reported that couples waiting for IVF treatment will occasionally drop off of the wait list because they become pregnant spontaneously.
To get a better sense of how frequently people going through IVF end up having babies without extra help, Dr Troude's group collected information on about 2,100 couples who started fertility treatment in France in the early 2000s. About 1,300 of those couples had 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.
Infertility means lower chance of pregnancy
Among the parents who'd had a baby through IVF, 17% later had another child without assistance. And among couples who originally failed to have a baby with fertility treatment, 24% 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," Dr Troude said.
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% became pregnant after failing to have a baby through IVF.
Birth rate overestimated
In 12% to 13% of couples in the study, the cause was unknown.
Dr Troude said unexplained infertility could be a good sign for couples' chances of having a baby, compared to those who have a clear reason for not initially getting pregnant.
Another recent study found that among couples who hadn't been able to get pregnant after a year or more of trying, 44% of those who opted against fertility treatment still ended up having a baby eventually.
Dr Johannes Evers, a professor of obstetrics and gynaecology at Maastricht University Medical Centre in the Netherlands, pointed out that the numbers in the study might overestimate the true birth rate, because only a little more than half of the couples who were invited to participate in the study actually answered the questionnaire, and pregnant couples might have been more likely to answer than disappointed, childless couples.
(Kerry Grens, Reuters Health, May 2012)
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