Introduction

• Pregnancy is timed from the first day of the Last Menstrual Period (LMP), and normal term delivery ranges from >37-41+6.
• The pregnancy is divided into first, second and third trimester, each trimester is 13 weeks.

Physiological changes

Pregnancy causes many physiological changes that need to be considered during maternal assessment.

• Cardiac Output increases 30-50%. As pregnancy progresses, cardiac output can be compromised by patient positioning as the uterus compresses the vena cava, consider position for transport to reduce aortocaval compression (Left Lateral Tilt OR  Manual Uterine Displacement).
• Tidal Volume increases by up to 40% at term. Lung capacity remains unchanged, and therefore maternal ability to compensate for increased oxygen demand is decreased. Monitor SpO₂ closely.
• Blood Volume rises throughout pregnancy up to 50% in the 3rd trimester. Plasma also increases, but at a slower rate, so the blood plasma concentration is effectively reduced. Maternal patients compensate for blood loss by restricting blood flow to the uterus. Therefore, physiological signs of significant bleeding may be a late sign and consideration for rapid transport should be made.
• Heart rate increases to approximately 85-100 at the end of the 3rd trimester
• Blood pressure falls in the first trimester.

Structured Assessment

• Gestation?
• Complications expected? (e.g. Gestational diabetes, Pre-eclampsia, multipara, mal-presentation, placenta praevia, previous complications)
• Membranes ruptured?
  • What was the colour of the amniotic fluid?
• Have contractions started?
  • Frequency and duration?
• Is there an urge to push?
• Fetal Movements:
  • increased or absent?
• Any current complaints? (e.g. Bleeding, increased blood pressure, pain, trauma)
• Maternal medical history, blood group and obstetric history
• National Pregnancy Records if available

APGAR:

APGAR was designed to help health care providers assess a newborns overall physical condition so that they could quickly determine whether the baby needed immediate medical care. It was not designed to predict the baby’s long term health.  ≥ 7 at 1 minute after birth is generally considered in good health. A slightly low APGAR score (especially at 1 minuet) is normal for some newborns, especially those born after a high-risk pregnancy, e.g. caesarean section, or a complicated labour and delivery. Lower APGAR scores are also seen in premature babies, who usually have less muscle tone than full-term baby’s and in many cases, will require extra monitoring and breathing assistance because of their immature lungs.

Pre-term Birth < 24 weeks

Not all bleeding pre-term results in loss of the foetus. However in most cases, a foetus will not be viable when born before 24 weeks. When delivered at less than 24 weeks, the foetus may present as tissue or developing human form (depending on length of gestation). Bleeding post-delivery is normal up to 500mls. Bleeding greater than 500mls requires intervention. Post-delivery the uterus will start to contract. This contraction will dislodge the Placenta and stem further bleeding. If the uterus does not contract post-delivery, the mother will continue to bleed (post-partum haemorrhage). Other reasons for postpartum haemorrhage include uterine rupture and genital tract lacerations. If the uterus has not contracted, first responders will try and stimulate the mother’s abdomen by rubbing to get the uterus to contract (fundal massage). In full term deliveries a suckling new born will cause the release of hormones which causes the uterus to contract. If bleeding continues, then an attempt is made to stem the bleed by applying pressure with a closed fist above the mother’s pelvic bone and pushing down towards her spine (suprapubic compression).

Birthing Complications > 24 weeks

This includes a mal-presentation (any presentation other than baby’s head ie. Breech, foot, arm or cord). Sometimes birth of a mal-presentation is inevitable – be prepared for resuscitation.

If baby is not born, placing mother in all fours position with head down will relieve pressure on both the mothers’ circulation and baby’s presenting part until help arrives. Unnecessary touching of any presenting part can increase foetal distress, this is unavoidable if baby is being delivered.

An airway check to clear meconium (green fluid) will assist baby to breath. Meconium in the amniotic fluid indicates baby has been distressed during the birthing process – be prepared for resuscitation.