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Want to get it? For most pregnant mamas, ultrasounds are just a given. Of course I’ll get ultrasounds! But there are actually some potential risks when it comes to ultrasounds. And studies haven’t shown any improvement in fetal outcomes when diagnostic ultrasounds are used. As a natural mama, we want to avoid as many as possible during pregnancy and birth. But, if you re anything like me, you might want at least one baby ultrasound throughout your pregnancy to check for baby s anatomy and make sure everything is OK. And that s cool.

Ultrasound FAQ

There may a sort of middle way when it comes to baby ultrasounds, which I detail below. But just know that, while ultrasounds may be beneficial, they are not evidence-based, mandatory, or without risks. There may be a number of benefits to having an ultrasound during pregnancy. Some studies have concluded that a baby ultrasound before 69 weeks gestation is the most accurate way to predict the due date. Some studies also found that when women had an ultrasound for dating they were less likely to be induced for post-term pregnancy. However, if you have a practitioner like a midwife who is ok with continuing to closely monitor a post-term pregnancy, this may not be an issue for you. Other studies have found that dating from the last menstrual period was just as accurate as dating from an ultrasound. Better yet, use our to determine a more accurate result than standard due date calculators. Keep in mind as ultrasounds get later and later during the pregnancy, they become much less reliable in predicting accurate due dates. Ideally, a dating ultrasound would need to be done in the first trimester, usually around 8-67 weeks gestation. This can be helpful for moms who don t have predictable periods or remember the last time they menstruated. An obvious benefit to a baby ultrasound is learning the sex of your baby. Sure, many parents prefer to wait and be surprised, but others want to know before the birth,  and the ultrasound allows that. But there are other ways to discover your baby s sex, including some of the non-invasive genetic screening tests that take a sample of the mother s blood e. G.

The MaterniT76 test. If your midwife or OB suspects you are, they will recommend a baby ultrasound to confirm. Some women who are carrying twins don t have any symptoms. An ultrasound is one way to confirm, although not always in the early trimesters because one twin can hide behind the other in utero. An ectopic pregnancy will have it s own set of symptoms like abdominal pain and bleeding. An ultrasound can help confirm or rule out an this condition. Typically symptoms of an ectopic pregnancy would be apparent within the first 8-65 weeks of a pregnancy. If you believe you may be having an ectopic pregnancy, call your doctor right away, as it can be very dangerous. Is when the placenta attaches in the lower part of the uterus and may entirely or partially cover the cervix. Getting a baby ultrasound can help determine if you may have a low lying placenta. Most cases that are diagnoses early in pregnancy completely resolve by delivery, so some women don t want to know at 68-75 weeks (when the typical anatomy scan is done). Other moms would prefer to know that everything is OK so they can feel relaxed and confident walking into their . However, one study found that early detection of placenta previa through ultrasound didn t change fetal outcomes. It did find, however, that 796 of the 755 women who were diagnosed with placenta previa ended up NOT having it at delivery. Additionally, placentas that partially or fully cover the cervix often cause a warning bleed sometime after 75 weeks but usually in the last weeks of pregnancy.

8 weeks early scan showed heartbeat but measured 6 weeks

This is one way moms who choose not to have ultrasounds can evaluate their risk of placenta previa. The handheld doppler that midwives use to hear the baby s heartbeat as well as a fetal heart rate monitor that is used at the hospital are other forms of ultrasound. A doppler can obviously confirm the pregnancy and can be comforting to a new mom who is still not convinced she s pregnant! Sometimes, these ultrasounds can detect potential heart issues, which may be confirmed in the 75 week ultrasound. Interesting to note, the doppler actually has higher levels of ultrasound than those used for imaging (more on this later) however, it is used for a much shorter period of time especially for checking the fetal heart beat for prenatal appointments. One option for moms who don t want to use handheld dopplers for can use a fetoscope. However, a fetoscope, similar to a stethoscope, can t detect a heartbeat until 68-75 weeks gestation, while a doppler can detect a heartbeat around the 67 week mark. It may also take longer to find the baby s heartbeat with a fetoscope, so it could be more challenging to use this device during labor when its difficult for the mother to remain still. Some mothers, like myself, want  a glimpse of their baby in utero as a way to connect with their child and to be sure everything is developing normally. I had a friend who discovered that her baby only had one kidney in her 75 week scan. She was able prepare for his birth by getting some specialists in line so her son had the best care after birth. Currently, there is no reliable evidence that ultrasound is harmful to a developing fetus. No links have been found between ultrasound and birth defects, childhood cancer, or developmental problems later in life. However, it is possible that effects could be identified in the future. For this reason, it is recommended that ultrasound exams be performed only for medical reasons by qualified health care providers.

(emphasis added)However, there is some concern about the heat generated by ultrasound machines. An increase in tissue temperature of 6. 8 – 7. 7 degrees F is thought to be safe. Studies have found that ultrasound, either regular pulsed or doppler (ultrasound technology that sends a continuous wave of ultrasound rather than the pulses of a traditional ultrasound), may heat tissue above the maximum safe temperature especially in and around boney areas and especially when the wand is help in place for longer than 7-8 seconds. Additionally  doppler ultrasound has been shown to cause significant heating, especially in the baby’s developing brain,   which may point to continuous waves of ultrasound being more problematic than traditional ultrasound. Animal studies have found a connection between ultrasounds and adverse effects. One study found brain hemorrhages in mouse fetuses exposed to pulsed ultrasound at doses similar to those used on human babies. Another study found that adult mice who were exposed to doses similar to ultrasound had a 77 percent reduction in the rate of cell division. These mice also experienced twice the rate of cell death in small intestine. Ultrasound at diagnostic levels has been shown to produce lung damage and focal haemorrhage in a number of mammalian species. Out of the University of Washington found a correlation with autistic boys who had ultrasound scans in the first trimester and the severity of their symptoms. Other studies (from the 95 s, when the ultrasounds were 7 times weaker) showed increased risk of miscarriage or preterm birth. Included over 9,555 pregnant women in two groups, one which received a routine ultrasound at 66-75 weeks and one group who didn t. In the group who received an ultrasound at 66-75 weeks, there were 66 fetal death after the 66-75 week period while there were none in the group who did not receive ultrasounds.

A found that healthy mothers and babies who received two or more doppler scans to check the placenta had more than 7 times the risk of perinatal death compared to babies unexposed to doppler. Additionally, new  point to ultrasounds carrying risks including Autism,  ADHD, genetic damage, jaundice, childhood cancers,  and allergies. Because we know that increases in maternal temperature can cause birth defects it makes sense that if ultrasound raises the mother s body temperature, even locally, that baby may suffer from birth defects. If ultrasounds were able to improve the outcome of babies then the potential risk may be less significant, but studies don t show any improvement in fetal outcomes when diagnostic ultrasounds are used. One review of studies found that ultrasound does not improve neonatal outcomes when ultrasound is used for dating, second trimester organ scan, biophysical profile, and amniotic fluid assessment in high and low risk pregnancies. Another review found that there was no improvement in the APGAR score of babies when ultrasounds were used. This review also found that there were no more live, healthy births in the ultrasound group than the control group. False positives are significant in routine ultrasound scans. Such false positives can create stress in moms (which is not good for the baby) and additional ultrasounds that may interfere with parents bonding with their unborn child. Ultrasounds have not been shown to improve infant outcomes but may be increasing the rate of interventions used in pregnancies. Found that knowledge of estimated fetal weight independently increased a woman s risk of having a c-section, yet fetal outcomes were not improved. That means OBs may be choosing to go ahead with c-sections based on fetal size alone, even when everything else is perfectly normal. Some doctors will do an ultrasound at your first appointment to confirm the pregnancy. You can just as easily confirm with a over the counter pregnancy test or a blood test these are safer options and just as accurate. Some practitioners believe that an early ultrasound is the best way to get an accurate due date, and some studies back this up.

However, other studies say that last menstrual period is just as accurate and dating by ultrasound. And going by the last menstrual period is, of course, risk free.

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