Obstetrics and Gynaecology — Preterm Birth and Fetal Growth, NMC MBBS licence examination syllabus (Nepal Medical Council).
When you cannot stop labour, the question becomes what you can achieve in the hours you have.
A woman arrives in early labour many weeks before her due date. The instinct is to try to stop it, and often that fails.
But stopping labour was never the main goal. The interventions that change whether her baby lives are mostly ones you can complete in a day or two — and knowing that changes what you do with the time.
A preterm baby is not a small term baby. It is a baby whose organs have not finished developing, and the crucial point is that every system is immature simultaneously: lungs that cannot stay open, no temperature control, a gut that cannot absorb feeds, minimal immunity, and fragile cerebral blood vessels.
Each of those is survivable alone. Together, in a baby weighing very little, they compound.
This explains the guiding principle: every week gained inside the uterus is worth having. The aim of treatment is usually not to prevent preterm birth altogether — often that is impossible — but to buy time, and to use that time well.Four interventions matter, and their relative importance is not what students expect.
1. Antenatal corticosteroids. Given to the mother, they cross the placenta and accelerate fetal lung maturation. This is the single largest gain available — fewer neonatal deaths, less respiratory distress, and less bleeding into the immature brain. If you remember one thing from this chapter, this is it.
2. Transfer the mother, not the baby. If delivery is expected and the local unit cannot care for a baby of that maturity, the woman should be moved before delivery. A sick preterm newborn tolerates transfer far worse than the pregnant woman carrying it — the mother is the best incubator and transport system available.
3. Tocolysis — to buy hours, not weeks. This is the point most often misunderstood. Drugs that suppress uterine contractions do not, by themselves, improve neonatal outcome. Their purpose is to create a window in which steroids can be given time to work and transfer can be arranged. Understanding that changes how the drug is used and when it is abandoned.
4. Magnesium for fetal neuroprotection where indicated by gestation and local protocol.
When membranes rupture before labour starts, two risks pull in opposite directions and the management is a judgement between them.
Delivering now removes the risk of infection ascending into the uterus — but produces a premature baby, with everything that entails.
Waiting buys lung and brain maturity — but the barrier between the vagina and the uterus is gone, so the risk of chorioamnionitis rises with every day that passes.
The balance shifts with gestation: the more premature the fetus, the more there is to gain by waiting, and the more willing one is to accept infection risk. Near term, there is little to gain and delivery is favoured.
Chorioamnionitis ends the argument. Maternal fever, uterine tenderness, offensive-smelling liquor, and maternal or fetal tachycardia mean the uterus is infected — and an infected uterus is dangerous to both. Delivery is then indicated regardless of gestation, because continuing the pregnancy risks maternal sepsis and fetal death.One practical point that prevents harm: avoid repeated digital vaginal examination once membranes have ruptured. Each examination carries organisms upward and shortens the time to infection. Where examination is needed, a sterile speculum gives the information with less risk.
Two babies measure below the expected size. One is perfectly healthy; the other may die before labour. Distinguishing them is the entire clinical skill.
A constitutionally small fetus is small because its parents are small. It is growing steadily along its own line, receiving everything it needs, and requires no intervention beyond recognition.
A growth-restricted fetus is not receiving what it needs — usually because the placenta is not delivering enough. It has stopped growing as it should, and it is at real risk of stillbirth.
The discriminator is the trend, not the measurement. A single measurement below average means very little. A growth trajectory that is flattening, or crossing downward across centiles, means a great deal. This is why serial measurement exists, and why one scan can never answer the question.And look for the cause in the mother. Growth restriction and pre-eclampsia share an underlying placental problem, so a woman with a poorly grown fetus needs her blood pressure and urine checked — and a woman with pre-eclampsia needs her fetus's growth assessed. Finding one should always prompt a search for the other.
This deserves its own section because the correct response is so often not given.
A fetus that is short of oxygen conserves energy, and one of the first things it economises on is movement. So reduced fetal movement can be the only warning sign before stillbirth — there may be nothing else at all.
The great majority of women reporting reduced movements have a healthy baby, and that is precisely the trap: the reassuring base rate makes telephone reassurance feel reasonable. It is not. She must be seen and the fetal heart assessed. The cost of seeing many well women is small; the cost of missing one compromised fetus is a preventable death.
And the counselling matters as much as the response: tell every woman what to report, and repeat it. A woman who has never been told that reduced movement is significant will wait until her next scheduled appointment.
Some risk is modifiable, and some is identifiable in advance, which is why history matters.
The strongest predictor is a previous preterm birth. A woman with that history needs to be identified early and followed more closely, because she is the person most likely to benefit from planning.
Other associations include multiple pregnancy, infection — particularly urinary tract infection — smoking, short interpregnancy interval, and heavy physical work with poor nutrition. Treating asymptomatic urinary infection in pregnancy is one of the few clearly effective preventive measures and is part of routine antenatal care for that reason.
No gestational thresholds, birth weight cut-offs, survival figures or drug doses appear here. Survival at any gestation depends on the neonatal facilities available, so a figure from a well-resourced unit would mislead elsewhere. Use your local protocol.
Create a free account to tick topics off, take notes as you read, watch the video lessons and get a day-by-day study plan built around your exam date.
Loading…