Risk Factors and Treatment Plans
Pregnancies are subject to a variety of risk factors. Maternity patients are classified as normal risk (sometimes referred to as low risk), moderate risk, or high risk.
- Normal risk implies the absence of any risk factors that may lead to a pregnancy complication(s) which would require the services of a specialist obstetrician. Most women are in this category and are appropriate to birth in a unit of any level, and could receive care from practitioners of any description including midwives, general practitioners or specialists. In general this category implies the birth at full term of a healthy neonate who does not require a paediatrician. These patients may deliver in level 2 or 3 maternity units. The need for caesarean section does not always necessitate a move to moderate risk.
- Moderate Risk implies the presence of fetal or maternal risk factors which may adversely impact on a pregnancy outcome. Management by, or at least consultation with a specialist obstetrician is compulsory. The birth will usually be in maternity units of a least a level 4. Preterm birth may be anticipated but this should not be less than 32 weeks. A paediatrician is likely to be required to care for baby.
- High Risk patients have major fetal or maternal risk factors which will always require management by a specialist obstetrician, and frequently management by, or at least consultation with a subspecialist in maternal fetal medicine. A birth in a level 6 unit will be necessary due to the potential need for neonatal intensive care facilities. In some cases a birth in a level 5 unit may be appropriate, depending on the availability of appropriate subspecialists for consultation, and if the birth at greater than 32 weeks is anticipated. (1)
As noted above, pregnancies identified as 'High-Risk' will be carefully managed through a treatment plan by your doctor. You may find further information by visiting the Women and Newborn Health Library at King Edward Memorial Hospital.
Risk factors affecting pregnancy can be defined into four categories; existing health conditions, age, lifestyle factors and conditions.
Please note this list is not exhaustive, and as we become aware of other evidence based factors we will add to this list.
Existing Health Conditions
- High blood pressure - Even though high blood pressure can be risky for mother and fetus, many women with high blood pressure have healthy pregnancies and healthy children. Uncontrolled high blood pressure, however, can lead to damage to the mother’s kidneys and increases the risk of low birth weight or preeclampsia.
- Weight - Obesity increases the chance of developing gestational diabetes during pregnancy.
- Diabetes - High blood sugar levels can cause birth defects during the first few weeks of pregnancy.
- Polycystic ovary syndrome (PCOS) - PCOS affects fertility and may result in higher rates of miscarriage, gestational diabetes, preeclampsia, and/or premature delivery.
- Kidney disease - Kidney disease affects fertility and any pregnancy is at risk of miscarriage.
- Autoimmune disease - Some autoimmune diseases can increase the risk of preterm birth and stillbirth.
- Thyroid disease - An over or under active thyroid can cause problems for the fetus, such as heart failure, poor weight gain, and birth defects.
- Prior adverse outcome of pregnancy - Sometimes there is no known cause of adverse outcomes in prior pregnancies. It is however, an indicator that risks may arise in future pregnancies.
- < 20 years - Pregnant teens are more likely to develop high blood pressure and anemia, and go into labor earlier than women who are older.
- > 35 years - Older pregnant mothers are at increased risk of:
- Caesarean section delivery
- Delivery complications, including excessive bleeding during labor
- Prolonged labor (lasting more than 20 hours)
- Labor that does not advance
- An infant with a genetic disorder, such as Down syndrome.
- Alcohol - Alcohol consumed during pregnancy passes directly to the fetus through the umbilical cord. Effects of alcohol consumption include increased risk of miscarriage, stillbirth, birth defects and fetal alcohol spectrum disorder.
- Smoking - Smoking during pregnancy increases the risk of preterm birth and sudden infant death syndrome (SIDS).
- Incompetent Cervix is when your cervix (the lower part of the uterus that connects to the vagina) softens, shortens (effaces) and opens (dilates) too early. This condition may also be referred to as an insufficient cervix.
- Gestational Diabetes can occur during pregnancy with short-term high blood glucose levels (blood sugar levels). If blood glucose levels are not controlled during your pregnancy, you may have a baby that is big, causing problems at birth. Baby may also have feeding and breathing difficulties after birth.
- HELLP is a group of blood and liver problems: H--Hemolysis is the breakdown of red blood cells. Red blood cells carry oxygen from your lungs to the rest of your body. EL--Elevated is liver enzymes. High levels of these chemicals can be a sign of liver problems. LP--Low platelet count. Platelets help the blood clot.
- Oligohydramnios is having too little amniotic fluid. Amniotic fluid is the fluid that surrounds your baby in the uterus (womb).
- Placenta Previa occurs when part of the placenta, or the entire placenta covers the cervix (opening of the womb). Placenta previa happens when the fertilised egg implants in the lower part of your womb and is usually picked up on ultrasound between 18 and 20 weeks. If you have placenta previa, you will probably bleed at some stage of your pregnancy. This usually happens after 28 weeks when the lower part of your womb is thinner and stretched.
- Placental abruption is when part of the placenta detaches from the wall of the uterus. This affects the blood and oxygen supply to the fetus.
- Pre-Eclampsia results in high blood pressure, protein in the urine, and may include swelling of the hands, feet, face and other parts of the body. It can develop any time after 20 weeks, although it usually occurs later in pregnancy.
- Preterm Premature Rupture of Membranes (PPROM) is defined as spontaneous rupture of the membranes before the onset of labour prior to 37 weeks gestation. It is commonly referred to as 'waters breaking early'. Your membranes form the sac that surrounds your baby and usually 'breaks' to indicate the onset of labour. When this happens before 37 weeks, it is considered PPROM.
- Twin to twin transfusion syndrome (TTTS) affects identical twins (or higher multiple gestations), who share a common monochorionic placenta. Depending on the number, type and direction of the connecting vessels, blood can be transfused disproportionately from one twin (the donor) to the other twin (the recipient). The transfusion causes the donor twin to have decreased blood volume. This in turn leads to slower than normal growth than its co-twin, and poor urinary output causing little to no amniotic fluid or oligohydramnios (the source of most of the amniotic fluid is urine from the baby). The recipient twin becomes overloaded with blood. This excess blood puts a strain on this baby’s heart to the point that it may develop heart failure, and also causes this baby to have too much amniotic fluid (polyhydramnios) from a greater than normal production of urine.
We recommend you speak with your care team for the appropriate treatment plan for your individual condition.
(1) Edited excerpt from Women’s Newborns’ Health Network "Framework for the care of neonates in Western Australia" March 2009