Justene Alpert terminated her pregnancy in December after her baby son was diagnosed with a "rare genetic disease".

The 36-year-old actress and her 35-year-old husband, actor Mason Trueblood, received the "nightmare" recommendation from doctors as she entered her second trimester and began telling their family and friends that they were expecting.

In a lengthy post shared on Instagram on Monday (22.06.26), the How I Met Your Mother star penned: "On December 22, my happiness, and if we are being completely honest, my light, was taken from me.

"It was a short phone call outside my office. It was calm and frantic at the same time. I was pregnant and entering my second trimester. My husband and I were just beginning the rounds of telling our close family and friends, and sadly, our little tour came to a halt that day.

"Our baby was diagnosed with a rare genetic disease. They needed to rush me to our genetic specialist to confirm the nightmare. He wasn't going to make it to full term.

"It's hard to swallow this news because I was looking at his little heart beating on the screen. He had the most beautiful profile. He had his dad's nose. I was ready for him. But then they pointed out the fluid, the organs, etc.

"I'll pause here. To the woman who is experiencing this or has experienced this before, I am mad for us."

Justene added that "no one prepares you for this".

She continued: "No one talks about this. No one briefs you on this when you are trying for a family. It's frustrating to say the least, and sad, and traumatic, and all of it, but I hope to maybe start a little wave in this pool of knowledge. OK, back to it."

A specialist warned the 9-1-1 alum that she would be "high risk" if she carried the pregnancy to term.

Justene added: "In situations like this, I've always been a 'shoot it to me straight' kinda gal. And then I heard the phrase that I never imagined hearing when we were ready to have a family... 'We highly recommend that you terminate this pregnancy, and we need to do it quickly if so.'

"Just then, the light that was in me blew out. I almost described the quickness as if you were standing on the side of the road and an F1 car flew by you.

"Your hair, immediately flipped up and slapped against your face so that when you try to look out, all you see are the infinite strands of hair that once outlined your face. That fast. Gone."

The Old Dads entertainer went on: "The next six days were a tour of a different kind. Let our parents know the once exciting news, now turned into a nightmare.

"My husband and I tried so hard to savour Christmas Eve and Christmas with our baby boy, fighting through the grief each day. We took long walks on the beach with [dog] Indy as a family of four and tried to just simply survive hand in hand."

Justene and Mason "had to say goodbye" to their son on December 29.

She recalled: "I was a mess, although I tried to walk into Pre Op with grace and poise. I kept repeating in my head, 'She is clothed in dignity and strength.'

"I felt so stupid because I couldn't believe that I was repeating a phrase that I see so much on home decor plaques. But it's a good phase.

"I'll share this, in case you feel alone or scared. Don't even try to be 'OK'. It's OK NOT to be OK. Bawling? Normal. Throwing up from the grief and trauma? Didn't know this...Normal."

The Matchmaker's Playbook cast member and Mason "desperately prayed for either a miracle or a miscarriage", and added that it "still feels unreal".

Justene said: "We didn't want to have to make this decision. No mom or dad should ever have to be put in this place. The shame and guilt is unfair. Having to do this is something that is rarely spoken of and seems to not have the same kind of empathy as other situations. It's the worst pain, and many suffer silently out of fear of being judged or simply misunderstood."

The A Recipe for Seduction performer went on to explain how she and Mason remained a "strong unit" amid the heartbreak, and that Justene "fell more in love with him".

She then thanked her family and friends for providing an "amazing" support system, which Justene and Mason are "so appreciative" of.

Justene ended her post with a message for their son, Mads Mason Trueblood.

She said: "To our baby boy, Mads Mason Trueblood, thank you for making me a mom. You are the one who gave me the backbone when I was doubting if I was ready to be a mom or not.

"Boy oh boy, kiddo, I was ready for you. I was ready to bling out a jersey with your number on it, to teach you how to play rough when your dad would walk away after his safety speech, to have a tiny protector, to give so many hugs and kisses to. I was ready to be yours.

"Your dad and I think of you every day, and I look forward to wrapping my arms around that sweet, beautiful boy with the most perfect profile. Until then, I know Finley will be glued to your side.

"I loved you then, I love you now, and I will love you forever."