PSA: you should get your ferritin (iron stores) tested. Especially women!! And especially if you get (or want to be) pregnant. I didn’t realize this was an issue for me, because my CBC (complete blood test: measures red and white blood cells, platelets, hemoglobin and hematocrit) results have always good, so doctors have always been happy. Roughly two years ago, I was feeling a lot of fatigue (and just generally felt off - like my nervous system was out of whack) and went down a health rabbit hole. My ferritin was in the 20s (below 30 ng/mL, you’re considered iron deficient). Doctors were dismissive, but I started taking oral supplements and felt noticeably, shockingly better (physically and mentally) as I gradually reached the 40s. That’s where I was when I got pregnant late last year. I started to feel pretty tired in the back half of my second trimester. Maybe this is just what pregnancy feels like? But thanks to DrGPT, I knew that pregnancy is an incredibly iron intensive process, so I asked my OB to check my ferritin. She did a CBC instead, and said everything was fine. I insisted on having my ferritin checked. She finally agreed, and my ferritin was 33 ng/ML, and obviously trending downward. I’ll spare you the drama, but after a lot of back and forth (and encouragement from a doctor friend that I wasn’t being unreasonable), I got a referral to a hematologist, who agreed we should try to bring my iron stores up. Not only is it important for the pregnancy, but also for breastfeeding and postpartum recovery (which in my experience, no one in healthcare focuses on beyond the six week checkup). I started doing weekly iron infusions in my third trimester. It took a week or two to kick in, but holy shit! I had my energy back. I felt fantastic during the stretch that’s supposed to be the most draining, all the way up until delivery at 40 weeks. When we last tested, my ferritin was at 122. In the hospital, multiple doctors and nurses marveled at my excellent CBC results post-delivery. Depleted iron stores can eventually show up in these other results, and some degree of anemia after giving birth seems to be treated as routine, especially given the blood loss. And while there are a ton of other factors, along with a lot of luck and randomness, I’ve felt pretty great in my first 3.5 weeks postpartum. Obviously this is just my experience, and health is incredibly personal. But I’ve seen people (majority female - we’re especially susceptible because we lose iron through menstruation) post on reddit and social media about single digit (!!!) ferritin scores and doctors who don’t seem curious or concerned. There's also early evidence linking low ferritin to fertility challenges, and suggesting that addressing iron deficiency may reduce miscarriage rates (there's also speculation that it could improve egg quality). This has been both a radicalizing and empowering experience for me, and I’ve been spreading the word 1:1…it’s shocking how many friends are dealing with a similar issue. Now that I’m on the other side of the pregnancy, I’m going to spend more time understanding the root cause for my low ferritin (Bryan Johnson seems to be on a similar journey). Happy to chat if helpful! Get your ferritin checked!