Michelle Duggar, star of the hit TLC show “19 Kids & Counting,” announced Thursday that she had suffered a miscarriage of her 20th child. During a routine check-up this week, a doctor was unable to find a heartbeat and told Duggar and her husband Jim Bob that they had miscarried in the second trimester.

According to Dr. Jennifer Landa, Chief Medical Officer of BodyLogicMD, miscarriage is particularly common at Mrs. Duggar’s age: 45.

“Risk of miscarriage is huge at her age. To put in perspective, risk of miscarriage generally is about 1:7,” Landa told FOX411’s Pop Tarts column. “At 20 years old the risk is 1:10, at 30 it is 1:7, at 40 years 1:3 and at 45, when it isn’t even all that common to get pregnant without medical intervention, the rate of miscarriage is a whopping one out of two pregnancies.”

Marcelle Pick, MSN, OB/GYN and co-founder of the Women to Women Healthcare Clinic, concurred that it was not unusual of someone of Duggar’s age to have a miscarriage.

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“Once you get over the age of 40—even after 35, it’s common,” she said. “I’m not surprised that she had a miscarriage. I’m sad for her. She has the baby that was premature and now this baby, but it’s not unusual when we look at the statistics of women over 40.”

Landa also said that the general reason for this is genetic abnormalities, which most often happen during the replication of DNA that must occur in the formation of an embryo that becomes a fetus and ultimately a baby.

“The chances for these genetic abnormalities skyrocket at her age because the eggs are essentially ‘older,’” she explained. “Mom is also at higher risk during pregnancy of gestational diabetes because of her older age status, and this has risks for baby too.”

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However, this isn’t the first complication the reality TV mom has been through. Duggar suffered a miscarriage when pregnant for the second time back in the 1980s, and the couple’s 19th child, daughter Josie Brooklyn was delivered via an emergency C-section four months premature almost two years ago. Weighing a mere 1 pound, 6 pounces at birth, Josie Brooklyn had to spend another four months in the hospital before being healthy and strong enough to be brought into the Duggar household.

“I would advise her to consider stop having children. In my opinion, she has a duty to the children she already has not to incur unnecessary risk that may occur with trying to have another child. She needs to be there for the kids she already has,” Landa added. “Additionally, her odds of having a baby with special needs are extraordinarily high and this may take away time and resources from the other children. I feel for her because miscarriages are never easy. There are lots of hopes and dreams that are born with each positive pregnancy test, but in my opinion, it is time for her to hang up the baby booties.”