PREMATURITY – causes, types, complications & more
Every normal pregnancy is expected to end at 9 months, approximately 37 to 42 completed weeks of gestation. Unfortunately, this period is prone to a host of risk factors from the mother or the fetus that can lead to an early delivery.
This early delivery can lead to a variety of complications, especially for the fetus. In view of this, what then is prematurity?
Prematurity is a term referring to the broad category of neonates born at less than 37 completed weeks of gestation. Currently, preterm birth is the leading cause of neonatal mortality and the most common reason for antenatal hospitalization.
The main cause of death stems from their underdeveloped organs, which may not be ready to function outside of the uterus. This normally is dependent on when they were born (gestational age). The gestational age refers to the number of weeks between the first day of the mother’s last menstrual period and the day of delivery.
The organs at risk of underdevelopment are the brain, lungs, intestines and immune system which leads to a greater risk of developmental problems, breathing problems and infections.
Based on the gestational age, premature infants are categorized as follows:
● Extremely preterm: Delivered before 28 weeks of gestation
● Very preterm: Delivered at 28 to before 32 weeks of gestation
● Moderately preterm: Delivered at 32 to before 34 weeks of gestation
● Late preterm: Delivered at 34 to before 37 weeks of gestation
Premature infants can also be categorized by their birthweight:
● < 1.0 kg: Extremely low birth weight (ELBW)
● 1.0 kg – 1.49 kg: Very low birth weight (VLBW)
● 1.5 kg – 2.50 kg: Low birth weight (LBW)
What then are the risk factors of prematurity? they are categorized into two, maternal and fetal risk factors. The following are the risk factors:
1. Maternal Risk Factors:
● Previous premature birth
● Maternal age (<15 years or >45 years)
● Previous multiple pregnancies
● Conception by assisted reproductive techniques (such as in-vitro fertilization)
● Little or no prenatal care
● Cigarette smoking
● Alcohol abuse
● Infections during pregnancy (such as urinary tract infections, sexually transmitted infections or infections of the uterus)
● Weak cervix (cervical insufficiency)
● Premature rupture of membranes
● Early separation of the placenta (placenta abruptio)
● Pre-eclampsia or eclampsia
● Renal disease
2. Fetal Risk Factors:
● Intrauterine growth restriction
● Hydrops fetalis
● Rhesus factor incompatibility
Now that we know the risk factors, in what ways can preterm births be prevented? Currently, the World Health Organization (WHO) focuses on 3 areas which are: midwife-led continuity care, kangaroo mother care and specific clinical interventions.
According to WHO, an estimated 15 million babies are born preterm every year – more than 1 in 10 babies around the world. This number is rising and appropriate care for the mother during pregnancy and childbirth, as well as LBW infants, is essential in reducing this increase.
1. Midwife-led continuity of care:
This involves a midwife or a group of midwives working together to provide adequate health care for a woman, newborn and her family throughout the antenatal, intrapartum and postnatal periods.
This is different from medical-led care involving medical staff and midwives.
Previous models done by WHO, noticed women having low risks of developing complications in pregnancy, fewer interventions such as instrumental births during delivery and safer spontaneous vaginal births.
For the success of this strategy, it involves access to emergency obstetric and neonatal care, either at a health facility or transport to a referral centre.
2. Kangaroo Mother Care:
This method of care is particularly for preterm infants < 2 kg. It involves exclusive and frequent breastfeeding in addition to skin-to-skin contact and support for the mother and infant.
It has been shown from previous studies by WHO that it reduces mortality in low and middle-income countries.
Currently, clinical trials are ongoing in various low and middle-income countries on Kangaroo Mother Care by WHO.
3. Specific clinical interventions:
These interventions include steroid injections before birth, antibiotic treatment when a mother’s water breaks before the onset of labour, and magnesium sulfate to prevent future neurological impairment of the child. The above mentioned are the interventions provided for the mother. The interventions provided for the newborn baby include thermal care, feeding support, safe oxygen use and treatments to help babies breathe more easily.