What is Stillbirth?
Stillbirth has no standard definition and the definition therefore varies in different countries. In the UK, stillbirths are those babies born dead after 24 weeks of gestation. In other countries, such as Australia, and many states in the USA, fetal death occurring after 20 weeks of gestation is termed as stillbirth. Instead of gestational age, some states use a fetal weight of 350 gm or more to define stillbirth.
Death may occur in the uterus at any stage of pregnancy or in labor. Most stillbirths occur prior to onset of labor and the most common symptom is loss of fetal movement. Some hours after the death of a fetus in the uterus, the skin begins to peel. On delivery, such a fetus is known as a macerated stillborn, as compared to fresh stillbirth.
Stillbirth vs Miscarriage
Stillbirth should be differentiated from miscarriage (spontaneous abortion) although the distinction is arbitrary. A death occurring prior to 20 (or 24) weeks gestation, or delivery of a fetus weighing less than 350 to 500 gm, or before a fetus is viable, is known as spontaneous abortion, while the loss of a fetus beyond this period is known as fetal death, fetal demise, or stillbirth. Stillbirth is also referred to as intrauterine fetal death (IUFD).
Causes of Stillbirth
Advanced maternal age, massive obesity, and high-risk pregnancies have been associated with stillbirth, although no definite cause may be found in a large number of cases. Of the known causes of stillbirth, one or more factors may be responsible for fetal death. These may include :
- Birth defects – may be due to chromosomal disorders, genetic or environmental factors. In some cases, no cause can be found.
- Placental problems – such as placental insufficiency, abruptio placentae, and placenta previa.
- Umbilical cord problems – such as true knots, cord round the fetus, abnormal insertion of the cord in the placenta, and cord prolapse.
- Infections – such as urinary tract infection (UTI), pelvic infection, toxoplasmosis, and parovirus infection.
- Pre-eclampsia and eclampsia.
- Use of medication that are contraindicated in pregnancy.
- Intrauterine growth retardation (IUGR) may predispose to stillbirth. Maternal hypertension (high blood pressure) or smoking during pregnancy may lead to IUGR.
- Trauma – either intentional as in domestic violence, or accidental such as a car accident.
- Rhesus incompatibility between the mother’s and baby’s blood.
- Fetal asphyxia (oxygen deprivation) during a difficult delivery.
Risk Factors for Stillbirth
Additional risk factors for stillbirth may be :
- Age – teenage pregnancy or maternal age over 35
- History of previous stillbirth
- Inadequate prenatal care
- Excessive smoking during pregnancy, including secondhand smoking
- Excessive alcohol consumption
- Narcotics and prescription drug abuse
- Maternal medical conditions – including hypertension (high blood pressure), diabetes mellitus, blood-clotting disorders, lupus, rubella, and jaundice in pregnancy.
- Multiple pregnancy – such as twins and triplets
- Exposure to environmental agents such as pesticides or carbon monoxide.
- Post-dated pregnancy
- Exposure to radiation
- Renal disease
- Hyperpyrexia – high body temperature (more than 39.40 C)
Diagnosis of Fetal Death
Stillbirth may be detected by :
- History – the most common symptom is loss of fetal movement. Vaginal bleeding or pain in the lower abdomen, back and pelvis may be present.
- Inability to detect fetal heart sounds by a stethoscope, Doppler ultrasound, or cardiotocography.
- Ultrasound can confirm the diagnosis of stillbirth – there is no fetal movement, such as heart beat, on ultrasound.
Stillbirth may be diagnosed after delivery.
Management of Stillbirth
Once stillbirth is diagnosed, the following has to be taken into consideration :
- Immediate delivery of the baby is usually not necessary unless there are complications.
- Spontaneous labor and normal vaginal delivery usually occurs within 2 weeks. If labor does not start within 2 weeks, or if the woman prefers to have an earlier delivery, labor may be induced. Labor is most commonly induced by giving an oxytocin intravenous drip to the mother to bring about uterine contractions.
- Induction is not always advisable if one of the fetuses in a multiple pregnancy, such as twins, has died. This is particularly relevant in case of babies sharing the same placenta since induction may jeopardize the living fetus.
- Cesarean section is rarely indicated unless there is some specific reason for it.
- Emotional support from the partner, family, and friends may help to cope with the tragedy.
Pregnancy after Stillbirth
Most women who have a stillbirth do go on to have a healthy baby in their next pregnancy. It is important to try and determine the cause of stillbirth, if possible, so that precautions can be taken in future pregnancies.
Postmortem of the baby, blood tests, and examination of the placenta may be done in an attempt to find out the cause. Subsequent pregnancies are not likely to be compromised in most cases, unless a genetic defect is found to be the cause of stillbirth. In such cases, consultation with a genetic counselor may be recommended who can assess the risk of birth defects and chance of recurrent stillbirth in future pregnancies. Maternal medical conditions such as hypertension and diabetes will need adequate treatment, and careful monitoring in future pregnancies.
The decision to try for another baby may be a difficult one. Some couples prefer to wait, while others may want to try as soon as possible so as to get over their loss. Most doctors advise waiting till at least 2 or 3 normal periods have happened before trying for a baby again, so that the maternal systems get time to restore to a normal state.