Alex Jones has urged people to stop judging women who have children in their late 30s as “selfish” in the wake of learning more about the difficulties surrounding fertility for a new documentary.

The TV presenter, 39, recently revealed she and her husband Charlie Thomson are expecting their first child.

Their baby news came after she wrapped filming on BBC documentary Fertility & Me, for which she delved deeply into the little-known facts about conception and the issues that may come with having a baby at an older age.

Alex JonesAlex Jones is pregnant with her first child ( Daniel Leal-Olivas / PA Archive/PA Images)

Writing in RadioTimes she said that, following her marriage to Charlie at the age of 38 last year, she knew “there was every possibility that, like one in seven couples, we’d struggle to conceive”.

She added: “But I found actual hard facts about fertility and conception hard to come by.”

The One Show presenter said it is “frustrating” that, when difficulties in conceiving arise, the blame is often aimed at the woman despite the fact “male fertility falls dramatically after the age of 40″.

She said: “Nobody brings that to the fore. It highlights just how much pressure falls on women.

“I came to realise that the best way to describe conception is ‘Russian roulette’. Women often blame themselves for miscarriage, but in a very high number of cases it’s actually the male sperm that causes the miscarriage.

“It takes two people to have a baby. I feel strongly that it’s very much a case of ‘they’ and ‘we’ as opposed to ‘she’ or ‘I’.”

Jones also expressed her disapproval that women who wait to have children – for whatever reason, be it not having found the right partner or not being able to afford IVF treatment – are labelled “selfish career women”.

She said creating the programme opened her eyes to how “heartbreaking and difficult” the process can be for those who struggle to conceive.

The programme features the TV host having tests to check her fertility, and discover what measures would need to be taken to maximise her ability to conceive with Charlie.

Alex Jones and Charlie ThomsonCharlie Thomson and Alex Jones (Ian West/PA Wire/PA Images)

She also looks into new techniques that are giving couples hope of having children, and meets the scientists behind these revolutionary advancements.

Alex Jones – Fertility & Me will air at 10.45pm on Tuesday September 20 on BBC One.

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