Empowered Pregnancy Education - The Placenta - Placental Insufficiency & Intrauterine Growth Restriction (IUGR) / Small for Gestational Age (SGA) / Fetal Growth Restriction (FGR)

By: Aunt Doula (02/24/2023)

IUGR, FGR, SGA? Which is it?!

It's all of them. All three terms have been used in literature, diagnosis' and by doctors of differing eras to name a condition in which is a fetus below the 10th percentile of growth, but growing in correct proportions. All three are the same diagnosis, used interchangeably, and confusingly - but all three have the same criteria. Currently, IUGR holds the top title of most commonly used diagnosis, so we will be continuing with IUGR for the rest of this article, but if you have been diagnosed with SGA or FGR, this still applies to you. Some providers will use small for gestational age as a way to explain IUGR, only furthering confusion and frustration for many people.

Placental Insufficiency is a diagnosis of its own, which is often not mentioned once the diagnosis of IUGR has been given - and that is often where a huge puzzle piece of understanding is lost. Placental insufficiency at its core is a lack of adequate (sufficient) blood flow due to a disruption in the network of vessels that connect the placenta to the carrying person and therefore from the placenta to the fetus. Without adequate blood flow, the fetus receives less nutrients and oxygen, causing a reduction in the rate of growth (growth restriction) that could otherwise be achieved with full blood flow.

Placental insufficiency has risk factors such as smoking, drinking, genetic abnormality of the placenta, certain medication use, having had an IUGR diagnosis on a previous pregnancy, and hypertension (high blood pressure) in the pregnant person. None of these causes placental insufficiency directly, we still don't fully understand the mechanism behind the broad presentations of blood flow problems, but these things make it a greater possibility that a placenta may struggle. However, someone may have none of these risk factors and still be diagnosed - and even if they did check a box or two above of risk factors, it is most important to know that there is no blame to be placed. There are pregnant people who tick many boxes of risk factors and have smooth pregnancies, and those who have been the healthiest person before pregnancy and still have faced IUGR. Here you will find no shame, so if you are feeling guilt or blame, take a deep breath and let it out. What matters now is learning about the condition and managing the rest of your pregnancy to the best of your ability.

In short, the most common reason for IUGR is Placental Insufficiency. The most common reason for Placental Insufficiency isn't known. Much like gestational diabetes, we may have risk factors that indicate a higher chance of developing the issue, but it also strikes pregnancies with disregard for risk factors. It is no ones fault they have placental insufficiency - a person can't control what their placenta does or does not do any more than any of their other organs!

What can be done?

The hardest aspect of placental insufficiency and IUGR is there there isn't much in the way of treatment or management to be done. Monitoring of the fetus and the pregnant person are increased to ensure that the best ratio of time in-utero is balanced with the benefits of being born early and take advantage of NICU care.

It has become generally common practice to have a carrying person begin taking daily aspirin in an effort to increase placentation - encouraging the placenta to create new blood vessel connections which can increase blood flow that was lost or reduced. It is also a consideration to start heparin which is a stronger blood thinner (anti-coagulant) to thin the blood to prevent clots in the placenta that are possible in cases of placental insufficiency due to a reactive biological process that often occurs when blood flow is disrupted and the lack of oxygen to the vessels signals the body to close off that vessel by sending a clot of fibrin. This cellular mechanism to deal with a poor performing vessel is also the mechanism that may chain further through the placenta; as blood flow is reduced, clots and fibrin fill the placenta, furthering the problem instead of providing a solution. When this level of damage is seen, heparin is often chosen instead of aspirin. Heparin also encourages placentation and has been shown to reduce inflammation and slow apoptosis (cell death) which can help to slow the process of vessels being clotted by fibrin to keep more vessels open, even if they are not at peak function. The goal of the Heparin is essentially calming the placental tissues and keeping them from cascading failure when an initial blood flow issue causes the clotting of vessel after vessel. It also encourages new blood vessels to form connections between the placenta and the uterine wall in the hopes that more flow can be restored and give the fetus more time in-utero with the better nutrient supply.

Both of these medication options should only be prescribed by your doctor and a plan made for how long you will take the medication, when you will stop taking the medication before birth, and what dosage is appropriate for your situation and health condition.

Some people increase their protein intake, take to bed rest laying on their left side, taking vitamin c, vitamin d, or other 'tips and tricks' found online but you should always talk to your doctor before drastically changing your diet, activity levels or vitamin supplementations. There are only certain situations where these additions may be helpful, and a balanced diet may be more appropriate even in the presence of IUGR.

What else should I know?

Placental Insufficiency may be found during any stage of pregnancy, but is most often discovered late in the second trimester or early in the third trimester. The earlier that placental insufficiency takes hold, the harder it becomes for a fetus to reach full term. Placental Insufficiency has also been associated with increased risk of developing pre-eclampsia, which is generally seen after week 20. Bio-physical profiles, special ultrasounds that include of the blood flow in the placenta and to the fetus may increase in frequency significantly if signs of IUGR and pre-eclampsia are present, as this indicates a danger to both carrying person and the fetus which only delivery can resolve. Depending upon how severe the IUGR becomes by the growth percentiles of the fetus, it may reach the point that it is better to deliver rather than wait to see if any interventions make a difference. Severe IUGR is defined as a fetus below the third percentile of growth. Blood pressure monitoring at home may also be indicated by your doctor to ensure early detection of pre-eclampsia high blood pressure events.

It is important to note that you can have pre-eclampsia after giving birth, it is not a well known fact that deserves much more attention - if you experience signs and symptoms of pre-eclampsia after giving birth, it is exceptionally important that you seek immediate treatment! Almost all information states that delivery of the placenta resolves pre-eclampsia, but this simply is not so. Any vision changes, high blood pressure, piercing headaches or shortness of breath should be treated as an emergency

Pre-eclampsia will have its own article linked here when complete

IUGR as a diagnosis should not stand alone. If you are told your pregnancy is affected by IUGR, it is important that you ask WHY and insist upon testing to discover the source of the growth restriction. Placental insufficiency is only one possible reason, and placental insufficiency should also be explored for a possible reason tho it is less likely to be able to find a direct cause. While placental insufficiency is the most common cause of IUGR, there are a number of umbilical cord anomalies that can reduce blood flow to and from the placenta, nutritional deficiencies of the carrying person that may need to be addressed, an undiagnosed metabolic disorder, genetic conditions confined to the placenta, prescription or non-prescriptiom drugs not disclosed, or another hidden process in the carrying person that needs to be explored. The complex reasons behind IUGR and the limited capabilities to treat it should not discourage seeking assistance. As stated above, IUGR is not the fault of anyone, including the carrying person, and the best place to focus attention is on the best ways to manage the condition to reach a healthy delivery goal that is safe for both the fetus and the carrying person.

Some pregnant people need to be hospitalized depending on the cause of IUGR to maximize the number of days that can safely be reached before delivery. Some deliveries if very close to 24 weeks may be delivered via c-section to ensure a fast hand off and minimal stress to the baby for care and treatment by the NICU team. If you have had a preemie delivery, r/nicuparents is an invaluable resource for this time.

Questions to ask your provider

IUGR is rarely a sudden occurrence, as a baby is monitored throughout pregnancy, there are often signs at the 20 week anatomy scan that could indicate a fetus that is not growing according to the average growth charts. This is typically mentioned when a fetus is below the 25th percentile that increased ultrasounds are suggested before 30 weeks to monitor if things improve on their own. Other early signs is a fundal height that is behind the gestational age which may indicate a need for an ultrasound. It should be at these times that you begin asking questions of your provider about what happens next, when, and at what points further interventions may be considered. A list of questions to ask include:

• What percentile of growth is my baby?
• What percentile would indicate a positive change by the next scan?
• What can I be doing to possibly improve the growth and environment for my baby?
• When would you recommend dietary changes or adding supplements?
• When would you recommend aspirin therapy?
• When would you recommend Heparin therapy?
• What is the cause of my baby's IUGR?
• Do I have Placental Insufficiency? What caused it?
• When should bio-physical profile scans become regular monitoring?
• How much weight does my baby need to gain between now and the next scan to continue growing in-utero?
• At what weight of the baby or week of pregnancy will I be able to consider an induction and trial of labor?
• What are the signs that the baby would need to be delivered immediately?
• Will I need to deliver at a different hospital?
• Should I have a consult with a maternal fetal medicine specialist?
• Can I tour the NICU wing/rooms and meet the staff?
• What week do you expect I will be able to make it to before delivery?

Some of these questions may be answered before you ask them, but some providers are not as forthright with information as you may want them to be. While you may put more weight to some. Of these questions than others, it is your right to ask every single question on this list and receive an answer or be given the steps that will get to the answer. As with any pregnancy complication, it can be scary to navigate and learn on the steep curve that you are on. It's okay if you left your first consult bewildered and confused, most parents do. Asking these questions at your next visit, over your electronic patient portal, or calling your drs office and asking to make a special appointment just to discuss these questions are all possibilities to consider. You did the best you could with what you had. Now you have more, so go do the best you can with it, and go from there. Keep pressing forward - you can do this.