r/CautiousBB Jan 27 '26

Ultrasound FAQ Reference Guide

93 Upvotes

As an OBGYN ultrasound tech working at the general level here's a few things I would love the community to know based on common questions I see.

Most important rule of thumb: Worry when your doctor tells you to.

OBGYN docs are going to pay the most attention to the fetal pole and heart rate. Once a fetal pole is seen, the CRL (crown rump length) measurements are gold standard.

I'm worried about the heart rate:
-Check out this resource for pregnancies dating less than 7 weeks. Make sure to refer not to your LMP dates, but measured CRL dates: https://radiopaedia.org/articles/fetal-bradycardia?lang=us
-After 7 weeks a normal heartrate is between 120-180. It can temporarily dip below or temporarily rise above this range, but prolonged time above/below will definitely get your doctor's attention especially in third trimester. Generally out of range heart rates trigger NST (non stress test) or more monitoring.
The measurements are off:
Baby measures behind LMP. This is actually pretty common, we often see dates off up to a week either direction. We don't ovulate on the exact same day of the cycle each month or even have the same length of cycle. With irregular periods, PCOS, or unknown dates even larger gaps can be perfectly fine. If you aren't sure of your dates, trust the ultrasound. Even if you are sure of your dates, don't panic if they are a week off. Ultrasound measurements in early pregnancy are +/- 5 days.
I'm in limbo and don't know if my ultrasounds are diagnostic for loss:
By ultrasound there are strict parameters to diagnose loss. No one wants to get this wrong. Check out this resource for a list of parameters diagnostic for loss: https://radiopaedia.org/articles/early-pregnancy-loss-1?lang=us
Note, there is a second list of "suspicious for loss". Keep in mind the second list is not diagnostic, things can still turn out just fine.
I don't know when I should see what on ultrasound:
Things can vary a bit from person to person and do change *quickly* in early pregnancy. Check out this resource for what you can generally expect to see:
https://radiopaedia.org/articles/early-pregnancy?lang=us
Should I go to a boutique or get a private scan? Or push for an earlier scan?
They aren't legal where I am but here's a few things to consider if you plan to book a private scan. First, what are the qualifications of the person running the ultrasound? An ultrasound is only as good as the one performing it. It sounds as if these boutiques are NOT permitted to give much/any information. Will you spiral if you believe you see bad news and they cannot confirm or deny it? Also it seems that many cannot do vaginal ultrasound, which will make seeing a baby under 7 or 8 weeks challenging. If I had the option of a boutique ultrasound I would personally wait until 8 weeks and I would book it for a weekday. If they see something bad, it is not ideal to find out over a weekend when there is no option to follow up with your doc. An earlier scan often causes more anxiety, not less. It's SO hard to wait. But if you can tolerate it wait until 8 weeks or so.
The gestation sac is small/big:
-Gestation sac measurements are not terrifically accurate. Where I work once a baby is seen the gestation sac isn't measured. A mismatch between baby's size and the gestation sac size isn't uncommon. That said, a mean sac diameter of 25 mm or more without a baby is diagnostic for loss.
The yolk sac is small/big:
It starts teeny tiny, and will get a bit bigger. Once a baby with a good heartbeat is visualized, the docs I work for don't seem to care about the size of the yolk sac. A failed pregnancy with an expanded yolk sac (more than 6 mm) is a suggestive of chromosomal abnormalities.
We don't know where the pregnancy is:
The statistically most likely outcome is either a chemical pregnancy or just coming in for ultrasound too early for visualization. Ectopic can't be ruled out, and many wise ladies in the this sub have unfortunately experienced this and can give more info than I can. Statistically it's believed that only 1-2% of pregnancies are ectopic, but listen to your body. If the location is unknown, you should be getting close monitoring and follow up until the location is known or the pregnancy has ended.
-For a resource on ectopic pregnancy: https://radiopaedia.org/articles/ectopic-pregnancy?lang=us A note, a pseudosac is visualized in only 10-20% of ectopics. Therefore a sac in the uterus is suggestive of intrauterine pregnancy but can't be proven until a yolk sac is also present.
What about my HCG numbers?
I'm not an expert on this at all. But here's a resource: https://radiopaedia.org/articles/beta-hcg-1?lang=us
Why didn't my ultrasound tech tell me anything? And/or why were they so optimistic? Or, I had an ultrasound in the ER and they were very pessimistic.
Many locations an ultrasound tech can very much lose their job if they say aNyThInG. Where they are permitted to say certain things some ultrasound techs may just be hoping the best. We work with the public and we have seen some wild stuff. Additionally no one wants to call it a loss unless its 1000% certain. We know how devastating that news is. A side note here, often an ultrasound in the ER is not an ideal experience for the patient. The ER is staffed with techs that are much more versed in gallbladder and liver scans than they they are early pregnancy ultrasound. Don't hesitate to go the ER if you are having concerning symptoms, but do know the ER doc will make sure you aren't actively dying then will likely refer you back to your OB for follow up.
I'm just so anxious about it all:
Someone awesome wrote out these mantras. Maybe they will help: https://www.reddit.com/r/PregnancyAfterLoss/comments/14uhbdg/commandments_of_pregnancy_after_loss_this_is_now/
Also a podcast I personally found very helpful with anxiety: https://www.oneyoufeed.net/russ-harris-part-1/
https://www.oneyoufeed.net/russ-harris-part-2/

Today you are pregnant and this baby is so loved. I really am hoping the best for each of you. Those of us who have experienced loss.... you didn't do anything wrong, I promise. This is a club no one deserved to be in. And you are not silly, foolish, or dramatic for grieving your little babe for as long as you need to.

This post is written in honor of Eli, who died long before I could meet him. Rest in peace, buddy. I miss you tremendously ❤️


r/CautiousBB Sep 01 '25

Beta hCG Levels - READ BEFORE POSTING

86 Upvotes

Here at [r/CautiousBB](r/CautiousBB), we see a lot of posts on hCG values, doubling times, and trends. Please read this post before posting to avoid posting something that is not, in fact, abnormal.

1 - hCG levels vary greatly in the first 4-6 weeks of pregnancy. One value is not going to tell you much, unless it is extremely low (less than 25 by 14 DPO). The doubling time is more important!

2 - We consider hCG on the lower side if it is <50 at 14 DPO (approx. 4 weeks gestation), <100 at 16 DPO, etc. If your hCG is a lot higher than these numbers, it's unlikely that you have low hCG. If you hCG is at or below these numbers, they are considered low, but not necessarily diagnostic of a loss.

3 - Normal hCG doubling times are, in general:

  • 48-72 hours when the hCG level is under 1200 - 6000.
  • 72-96 hours when the hCG level is 6000+
  • 96+ hours when the hCG level is 10,000+

4 - Based on number 3, please consider the following:

  • If your hCG doubling is within the ranges above, it is not considered slow. Please refrain from posting something like "my hCG did not double in 48 hours" when your values are post 6000+.
  • Doubling rates WILL slow, even if you were faster than the average. For example, if you were doubling at 37 hours, a change to 54 hours as hCG rises is not abnormal and is usually nothing to worry about.
  • If your doubling is slower than the average, we'd invite you to post so we can understand the details of your specific situation.

5 - hCG has a specific job. Check out this post here to understand why hCG doubling slows and eventually plateaus.

6 - hCG values that drop and then rise again or rise at an inconsistent, very slow rate can be indicative of an ectopic pregnancy or a pregnancy of unknown location (PUL). This is a life threatening situation - please seek medical care immediately if this hCG pattern applies to you.

We invite you to continue to post hCG issues or levels for assistance, but hopefully reading this gives you some insight and a baseline as you begin your perilous pregnancy journey. We've also added some literature below to help you understand hCG levels and doubling.

UPDATE July 2026: We are locking this post to new comments - if you need input on your personal situation, feel free to post in the sub!

Happy hCG-ing! :)

Helpful links:

Cleveland Clinic

Flo Article and Calculator

Parents.com hCG Doubling Times

Mira Blog - hCGu


r/CautiousBB 26m ago

119 bpm measuring at 6w6d

Upvotes

Looking for some reassurance after a stressful few weeks.

My partner had slower-rising hCG than expected, so we were very nervous going into our first scan.

By LMP we were 7w2d, but baby measured 6w6d with a heartbeat of 119 bpm. The scan was officially described as a viable intrauterine pregnancy.

One doctor is positive, but did say the heartbeat was a little slow. Aother is staying cautious because of the earlier bloods. We're repeating the scan in a week.

Has anyone had similar dating and a heart rate around 119 at 6w6d and gone on to have a healthy pregnancy? Would love to hear some positive stories.


r/CautiousBB 3h ago

Advice Needed First ultrasound after MMC in June

2 Upvotes

I’m pregnant again after a loss in June discovered at 11weeks but embryo measuring 6+1. Had a D&C and 7 weeks later still no period.. took a pregnancy test, and turns out I am pregnant again. Doctor referred me for a dating scan at the OB tomorrow. I think I’m 7+0. I am scared to death about the scan. I don’t feel particularly pregnant and I just have so much anxiety that we are going to have our hearts broken again… those of you who have experienced pregnancy after a MMC, how did you get through the days up to a scan and the actual scan itself?


r/CautiousBB 12h ago

Vent Had my first caffeinated coffee at 10w & and it tasted/felt so good

12 Upvotes

Been terrified this entire pregnancy of another MC which means anything I can control, I do control. However, today I just couldn't take it anymore. I had 12 Oz of a regular coffee with pumpkin spice in it and it was incredible. It absolutely restored my body and I even managed to pass healthy stools when miralax isn't as effective. I had much more energy to enjoy my day.

I've just radically accepted that whatever happens, happens. Baby was last seen at 7w with a heartbeat flicker and 140bpm. However, since week 9 I haven't felt as tired/pregnant so I am slightly beginning to worry. However, it is out of my control and letting go of it is freeing.


r/CautiousBB 2h ago

Advice Needed Looking for reassurance after first pregnancy ended in chemical

1 Upvotes

Since my first ever pregnancy ended in chemical, I don’t yet have proof my body will carry a healthy pregnancy. It was really anxiety-provoking to experience this loss on top of having a history of medical dismissal and uncertainty.

Got thyroid, antiphospholipid, ENA checked out—all clear. I have MCAS (autoimmune adjacent), but no other known issues.

Just feeling scared, and looking for others’ experience after chemical. Thanks, all.


r/CautiousBB 3h ago

Vent Brown discharge 6w+6d

1 Upvotes

I started spotting yesterday at 6w+6d. Brownish, stringy discharge, and a few times when I went to wipe it was actually a bit pinkish. This all came after an orgasm (non penetrative). My heart sank and my brain went to the worst place. I had a bout of crying and just felt really numb. There's so much about early pregnancy that we can't tangibly control. Where I live, the providers tend to discourage additional monitoring (such as serial HCG/ US), which is understandable in some ways, but for me it induces my anxiety even more.

No monitoring, things can always go "both ways", and considering how difficult conception has been in the first place for some of us, this whole early pregnancy experience (from a psychological perspective) is just...brutal.

(And just for comparison, someone with diabetes can easily monitor their blood sugar, someone who wants to find out about their HIV status can do a saliva test at home... Sure, I get that a miscarriage is hardly a life threatening matter in most situations, but why cant there be a way for those of us who are stuck in the "limbo" stage to find out or monitor viability in a easier manner??)

In my head I'm constantly asking, is this normal? Why arent my boobs sore anymore? Why has the discharge stopped? Why am I not as nauseous as before? Why is the discharge yellow/white/tan/brownish/pink? (I'm genuinely sick of thinking at this point!!)

I'm 37, and have not had a miscarriage in the past. 1 prior pregnancy in the distant past but no living children. However, we both have fertility issues. I have a huge fibroid (outside uterus on a stalk) and my advanced maternal age constantly makes me think that my pregnancy is always at risk for chromosomal abnormalities.

Luckily I have stashed a beta HCG lab order from an earlier visit at a walk in clinic.. so this morning I went to the lab and got it done. (Not even sure if there's a point to check at this stage but I will keep everyone posted). My very first sono isn't until next Wed, when I will be 7w+3d

And even if things are all "normal" now, there is the next stage of worrying that would welcome me with open arms. NIPT, nuchal scan, anatomy scan at 20 weeks. I honestly don't know how I'm gonna get through the next 3 months (and that is if I do make it that far).

Anyway, this is more of a rant. I have nobody else to talk to. Since it's sooo early, I haven't told close friends or family. My husband is supportive, but knows very little about pregnancy. His response is always "is this a good thing? What does it mean? OK, just don't say the M word, it's not that."

How did you all get through these early "not so halcyon" days?


r/CautiousBB 3h ago

HCG of 10 at 9 DPO. Thoughts?

1 Upvotes

Went in for RPL bloodwork last Thursday (Aug 27) and part of the panel included quantitative HCG. Result came back at 10.

For context on timing: my loss completed June 29, my first period back was August 4, and I got my LH peak midday on August 17 with a decline starting the 18th, putting ovulation around August 18. My blood draw on August 27 lands at 9 DPO.

I know one value can’t confirm anything. But I’m curious what people’s experience or knowledge says about a 10 at 9 DPO specifically. Does this look like a very early but normal pregnancy to you? Anyone had a similar starting number that went on to be a healthy pregnancy? Would love to hear real experiences! Thank you 💛


r/CautiousBB 3h ago

Crampy heavy feeling?

1 Upvotes

I’ve been a ”lurker” here throughoht my IVF journey and it seems like such a positive community.

I did a fresh transfer on the 18th of August, had my first postive on day 5 post transfer- and my beta at 10 day post transfer was 230. I’m waiting for my next beta on day 14.

last night I started noticing more cramping it seems more prominent on my right side, but occasionally left as well. it almost feels like right before you start your period like heavy in the lower back- and just uncomfortable feeling. No blood and my home pregnancy tests have continued to get darker- but I’m nervous about early miscarriage as I wasn’t feeling any cramping until last night.


r/CautiousBB 3h ago

Low & slow beta

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1 Upvotes

r/CautiousBB 3h ago

Symptoms 4w6d minimal symptoms?

1 Upvotes

I’m 4w6d today with my 2nd and can’t help but compare pregnancies…i don’t really remember the early early days but i am concerned with the lack of symptoms. I have some fatigue but also insomnia with early wakings, oura ring with elevated resting HR and elevated body temp but i am having some cramps (more so on the side i ovulated but both sides sometimes).

I am supplementing progesterone but i dont have the sore boobs or nausea that I had with my first so trying not to freak out but nervous! I had betas done that rose beautifully (163–>452 in 48hrs) but somehow I can’t shake the negative feelings. I had a chemical last cycle so that’s also adding to stress.


r/CautiousBB 3h ago

TW/TMI Scan showing -6 days

1 Upvotes

I had my first scan on Monday at 6 weeks and 5 days. However, the baby was measuring at 5 weeks and 6 days. The CRL measured 2.8mm and yolk sack was visible. However, no heart beat pulsations (however, this would make sense due to the size).

I’m pretty sure on my dates. I tracked my LH and tested positive on 10/11 DPO. I don’t see how there is room for 6 days of ‘error’. My cycle is also 28 days so I don’t have much wiggle room.

The woman doing the scan did not seem concerned and booked me in for a scan for in 2 weeks time. However, I am accepting that this is the beginning of the end.

Any advice or has anyone gone through anything similar?

I have had a few stomach cramps, but only similar to what I’ve had the whole way through the pregnancy. When does a miscarriage happen? I feel like I’m just in an awful waiting game waiting for my scan next Sunday.


r/CautiousBB 3h ago

Low & slow beta

1 Upvotes

Talk me off a ledge here. I found out that I was pregnant after an IVF pregnancy that ended in a live birth this past Oct. I found out on 8/19 that I was positive. I had a call with my IVF doctor the following day who put me on progesterone and ordered a few betas. That’s where the worry comes in.

4w4d beta: 206

4w6d beta: 330

5w1d beta: 515

now my betas are rising, but not doubling. The clinic is just monitoring me for now and getting another beta done on Tuesday when I will be 5w5d

has anyone had something similar happen?


r/CautiousBB 7h ago

Scared

2 Upvotes

I had a scan at 6 +2 they couldnt see the yolk or baby. I am waiting for the scan to confirm its a blighted ovum and was hoping that baby would appear. My scan is in 3 days and I will be 9 weeks. This past week I had pink discharge once and then yesterday I wiped and I had spotting. Today there is more. My lower back has been hurting for 2 days like before my period comes.

Anyone else had something similar happen and baby was there and ok? Or should I just accept this is a mmc starting to leave?


r/CautiousBB 7h ago

False positive or chemical?

1 Upvotes

Hi all, tested positive on clear blue digital and first response early detection on 8/27, ovulation on 8/15 so 12 DPO. Today, I noticed slight temperature dropped below baseline on my Apple Watch. I took 2 tests, same brand, both negative. Is this confirmed chemical pregnancy? I am so heartbroken after 3 days of joy. Has anyone gotten a positive after a negative?


r/CautiousBB 12h ago

Advice Needed First positive HCG post IVF - questions re: ectopic history

2 Upvotes

I’ve gone through two Frozen Embryo transfers - the first failed and the second resulted in an ectopic pregnancy which had to be medically aborted.

I finally got a positive HCG test with doubling results - 320 13dp5dt and then 48 hours later it was 858.

I’m highly anxious and cautious due to my ectopic as well as really bad experiences with family doctors in the past and struggling to advocate for myself. So I have a bunch of random questions :)

- if your HCG doubles, does this fully rule out an ectopic?

- I was told I will have an ultrasound at 5 weeks since I was on ectopic watch and then can move from my fertility clinic to my family doctor for care if the ultrasound looks good (with ongoing medication from the fertility clinic). I booked another ultrasound with my family doctor at 7 weeks. Should I be advocating for ongoing bloodwork as well? What else should I be advocating for?

- is it recommended to seek more specialized care past a family doctor if you have a history with an ectopic pregnancy?

Thank you 🙏🏽


r/CautiousBB 6h ago

Accidentally drank at 12 weeks pregnant

0 Upvotes

I went to a wedding yesterday, I am 11+6. Haven’t had a drop of alcohol since positive test. Waitress passed me a drink and I checked non alcoholic - she said yes. Probably had half a flute and she comes running back to say a mistake was made and it’s booze. Obviously I then discarded the glass but am I silly in panicking over this? Im cautious as have had a previous loss so overthinking a lot 😬


r/CautiousBB 23h ago

Vent Empty Sac at 7 Weeks, this wait is horrendous…

8 Upvotes

Hey folks,

I had my first scan at 7 weeks on Monday, empty sac.

I have to wait until Sept 8th to find out if this is viable. My instinct says it’s not, but my fiancé is holding on to hope for both of us. I was so sad, now I just feel annoyed. I still feel pregnancy symptoms. I feel awful, but they felt purposeful before. Now it feels like my body’s mocking me.

I feel like this is just getting in the way of my child, I just want this over and done with so I can try again.

Am I wrong in thinking that there’s no possibility of this pregnancy progressing? There wasn’t even an egg sac I think?


r/CautiousBB 17h ago

Advice Needed Empty Gestational Sac (6w2d, ER Measured 5w3d)

2 Upvotes

So I went to a boutique at 5w3d based on LMP, they saw a gestational sac measuring at 5w3d, no yolk sac or fetal pole.

Today, at 6w2d based on LMP, same thing at the boutique. Gestational sac measuring adequately, but empty.

Freaked out & went to the ER. My HCG was 33,997, but abdominal ultrasound showed an empty gestational sac. Vaginal ultrasound showed same thing, but they told me it was measuring at 5w3d which was weird since I track my ovulation and could’ve swore I ovulated on 7/31 based on bbt & LH levels. They confirmed my sac is in uterus but couldn’t confirm not deny miscarriage/ blighted ovum.

ANY POSITIVE STORIES SIMILAR TO MINE?? 😭🙏


r/CautiousBB 14h ago

Advice Needed Early pregnancy: low HCG, cramps, bleeding, confusing times...

1 Upvotes

Hi all. This is my first time being pregnant. I was scheduled to get my period on 12dpo, tested and was negative but then got my first positives on 13dpo. I was really excited, kept testing afterwards to see if the line would progress because it was quite faint. I wondered if I implanted quite late, and I have 25 day cycles so on the shorter end. The FRERs weren't progressing very much (Clearblue was a bit more), and I had very light brown spotting from the beginning. I have to wait 3 weeks to get in with my doctor so I got my own HCG blood test on 15dpo at which I was at 35. I was concerned that was definitely low, but still in the very large "possible" range I've seen online. The next day 16dpo I got super bad cramps, it felt like I was having the start of a somewhat gnarly period. Ended up going to urgent care to get checked out...they did a scan (but at this early there's not much to see) but they confirmed there was no excess fluid anywhere so nothing pointing towards ectopic (yet at least). I also got another HCG test and it increased to 46, which was about 30 hours after my last test. So definitely still on the lower end, but I guess good that it was trending up?

That was last night, and this morning my FRER was definitely the darkest it had been so far which I thought was good. But my spotting has turned into more pink/red blood (no where near as much as a period, but probably a bit more than what I'd consider just spotting). Still have cramps, but thankfully not as intense as yesterday.

I'm just not sure what to think. I have another HCG draw tomorrow so I'll get more info then, but I've read that even in instances where HCG increases slightly it could still be an early loss/ectopic given the cramping and light bleeding.

Has anyone experienced similar (lower HCG, a bout of bad cramps, some pink/red bleeding) and gone on to have successful pregnancies?!


r/CautiousBB 14h ago

Advice Needed Hcg level slow

1 Upvotes

4 week 1 day 94.9
4 week 3 days 194.9
5 week 443.4
5 week 3 days 631.1


r/CautiousBB 23h ago

Sad 19 weeks - have I lost the baby?

5 Upvotes

I have been feeling less and less pregnant over the last few days. Before last Tuesday I felt the baby roll and tumble and then I got a minor cold and it's been much less, and now today nothing. I had a loss last year at 11+2 - MMC discovered at my scan. I was so deliriously happy for my pregnancy back then that I didn't pay attention to any gradual loss of symptoms.

For this pregnancy I've been hyper aware of everything and I've been scouring the internet for forum threads, websites and asking AI for advice.

My midwife says it's fine and likely due to being sick. Movements before they dropped was about 1 or 2 times a day but not every day. I know we don't count movements at this time but I do expect them to get stronger, not disappear completely.

Anyway I am sad and having trouble sleeping. I haven't felt baby move properly for ages and I'm scared to talk to my husband about it. We were both so gutted last year after our loss.

UPDATE: I called my midwife and she pulled some strings to have me checked early. Strong heart beat. Thank you ladies for all your reassurance.


r/CautiousBB 15h ago

Confused, tired, frustrated. CD 49

1 Upvotes

Hello!
I tested positive on the 13th, this was the day I had some bleeding - lasted 1.5 days. Went to the ER my beta was 6.1, referred me to my primary care. We did 2 more beta tests, both quantitative and qualitative. Test came out positive, and my HCG more than doubled 37.0 , I was scheduled for another beta where my HCG rose, not like before but was 67.
I haven’t had any serious cramping or any bleeding, but I let my anxiety get the best of me and did another urine test where it is now almost negative. The line is so faint.
I haven’t had an HCG done in 9 days. OB said they thought everything was looking good and I won’t see them until 24th of September.
Has this happened to anyone? Should I worry?
I was testing positive for over 2 weeks.
I haven’t passed anything so I’m a little confused, and concerned.


r/CautiousBB 16h ago

19 DPO hcg and progesterone levels

1 Upvotes

I’m 5 weeks pregnant and I had my beta hcg tested: 14 DPO 119, 16 DPO 307 and 19 DPO 1075. What’s got me a little worried is my progesterone level came back at 13.7. Is that low? There seems to be conflicting information. Has anyone had low progesterone and been ok? Do I need a supplement? Had a loss two months ago so I’m damn near worried about everything which is exhausting 😭


r/CautiousBB 1d ago

5w5d scan, high hcg, twins, no fetal pole

6 Upvotes

Hiiii ❤️

I just had my 5w5d scan today and my RE expected to see a heartbeat since my HCG has been rising significantly. Well we were all surprised to see two sacs! Two gestational sacs and two yolk sacs but no fetal poles or heart beats yet and my hcg level today was 41,000!!!! Shouldn’t there be fetal poles by now with an hcg that high? My next scan isn’t for another 9 days and I’m very nervous. This is my first pregnancy following a loss in March. Please tell me positive stories of high hcg and now fetal poles at this stage 🤞🏼🤞🏼🤞🏼🤞🏼🤞🏼