Fitness tracker FitBit can help you get pregnant.
Resting heart rate data collected from the £90 wrist-worn devices can “accurately” inform women “precisely” where they are in their menstrual cycle, experts have found.
It suggests women could use the health monitors to help them conceive by getting a 24-hour heads up just before they approach their most fertile days of the month.
The findings were presented at Europe’s biggest fertility conference in Helsinki, Finland.
In the study, German scientists tracked the resting heart rates of five women throughout the menstrual cycle.
The women also underwent daily urine tests to determine where they were in their cycle – and see how closely aligned the heart rate data was to their cycle.
For the first time, the experts discovered a direct correlation between the resting heart rate data from the FitBit devices and the four menstrual cycle phases.
They said this means that women could use wearable technology to track their heart rates, and use their unique data to help them conceive.
Speaking at the annual meeting of the European Society of Human Reproduction and Embryology, German health firm BioWink’s scientific research director Dr Vedrana Tabor, who led the research, said: “By tracking your heart rate alongside your cycle, you can gain a far better understanding of your fertile days.”
The study collected data on resting heart rate, ovulation, menstrual cycle length and period duration in five women aged between 25 and 40 for around a year.
Researchers found a rise in the women’s resting heart rates on the FitBit Charge HR trackers shortly before ovulation – similar to the already well known body temperature rise.
They suggested that if women tracked their resting heart rate via the fitness tracker, they could get a 24-hour warning when they are hitting their most fertile stage of the month.
In a written abstract of the study, the research team said: “Electronic wearable technology measuring number of daily steps/distances, sleep and parameters such as heart rate can be used to determine different phases of menstrual cycle.”
But a British fertility expert cautioned that while women may well benefit from ovulation data, they shouldn’t necessarily burden their partners with that information because that might put too much pressure on the men to perform.
Prof Allan Pacey, of the University of Sheffield, said: “The single biggest idea I hear when couples are talking is the idea they have got to monitor ovulation.
“So you have a disconnection between couples, where the man is told you can’t ejaculate for a fortnight because, two weeks on Tuesday, she reckons she is going to ovulate.
“The next thing that happens is he’s at work, all stressed and she sends him a text, saying ‘You’ve got to come home and s**g me now.’
“He gets all wound up in the traffic on the way home, he bursts through the door and she’s on him like a panther.”
Instead, Prof Pacey suggested that “cleverer” women trying to get pregnant should perhaps use data from new medical technology devices like a FitBit to help inform them when may be the best time to try and conceive, but then not necessarily burden their partner by telling them “tonight’s the night”.
He added: “It just is not conducive to healthy relationships.
“So he’s pretty p***ed off, so what I say in all the talks that I give is ‘Ladies you are far more clever than that. Buy your kit from Boots, plan your evening, but just don’t tell him about it.
“Get him home. Curry on. Beer. Let him go through the motions of having his belly full, and then jump on him and you’ll get what you want and he won’t know any different.”
Prof Pacey added: “One of the biggest issues, I think, is men suffering from performance anxiety, or just being turned off, when women are fixated on a time or a date, a day or night which she has decided is the best time to try [for a baby]. There’s no problem with women using data if it helps them better plan things, but you don’t want to undo that benefit by sharing too much of that with him, and risk putting him off. It just causes strain and strife.”