Fetal Heart monitor... Has anyone done one??? - Page 1
Forum section: electronics / projects

author: m12lrpv
author_rank: Regular Contributor
timestamp: July 16, 2012, 05:41:44 am
content: With another one on the way and my own developing interest in hobby electronics I thought that making a fetal heart monitor might be a neat project.Except it seems that there isn't much out there in the way of circuits which is a bit of a surprise. I would almost have expected it to be standard fare for an EE dad to beI found one circuit for a microphone based one which i'm going to make up but also i'm interested to know if anyone has done an ultrasound doppler version. With the easy availability of ultrasonic transducers it seems like a reasonable project to attempt.I did find some info in a freescale app note but it was little more than a high level overview to a beginner like me.Does anyone have any ideas on how to do a doppler based fetal heart monitor?

author: saturation
author_rank: Super Contributor
timestamp: July 16, 2012, 05:18:43 pm
content: While it is possible to build one, its alas, cheaper to get one premade and modify it if need be.http://www.ebay.com/itm/Prenatal-Fetal-Doppler-Heart-Monitor-Pocket-Sonoline-B-/180928675678?pt=LH_DefaultDomain_0&hash=item2a20307f5eA problem with building it, is where are you going to test it to debug it?There are just 2 problems, if the transducer malfunctions and you try to output too much energy, there is a risk of thermal injury at the contact point and deeper, or worse, injuring the fetus.If the baby is still born or worse, alive but deformed, can it be said with absolute certainty, the device did not contribute to the injury?There is speculation that US for any use during fetal development may have unexpected effects:http://www.ncbi.nlm.nih.gov/pubmed/21874769http://www.ncbi.nlm.nih.gov/pubmed/20149552http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1265028759369Given the risk/benefit of a consumer doppler, it would strongly advisednotto use fetal US unless absolutely necessary, and only by care givers.

author: olsenn
author_rank: Frequent Contributor
timestamp: July 16, 2012, 05:25:35 pm
content: It always amuses me when I hear people on here are creating ad-hoc medical devices to be used on their children. I don't mean to imply that you are puting anyone at risk with what you're doing, but seriously, just go buy a cheap heart monitor at your local drug store.Quote of the day: A real man doesn't need to waste money on a baby thermometer... I can just use my Fluke-87 and a type-K thermocouple!

author: m12lrpv
author_rank: Regular Contributor
timestamp: July 16, 2012, 08:53:23 pm
content: I take on the board the safety issue raised. I'll just build the passive audio one then.Still it would be nice to know how to make one and the theory behind them which was my initial drive.It's a shame that there is a world out there where people are so risk adverse that knowledge has to become secret.

author: digsys
author_rank: Unknown
timestamp: July 17, 2012, 12:54:51 am
content: QuoteWHOAA, that's WAAAY out of the ballpark !!Having designed medical U/Sounds, I can tell you that this is NOT an experimental area, for ANY living species. The responses aretrying to prevent you from maiming or killing !! It only takes a few seconds of cavitation to BLOW APART a blood vessel or organ !!And NO ONE is keeping secrets from you ! WE'RE not assisting you in damaging living material.If you want to learn Ultrasound, I'D suggest you start on things like ultrasonic cleaners, plenty of info out there for that.

author: m12lrpv
author_rank: Regular Contributor
timestamp: July 17, 2012, 01:01:54 am
content: Quote from: digsys on July 17, 2012, 12:54:51 amWay to support my statement.